Dissertations / Theses on the topic 'Seed coatings'

Thiamethoxam and clothianidin are two neonicotinoids used in seed coatings for crops such as corn and soybeans. Both neonicotinoids have high solubility in water, so they are prone to transport via leaching and runoff. This thesis is comprised of two studies that evaluated potential solutions to mitigate neonicotinoid transport from fields. The first study examined the relationship between soil organic carbon content and neonicotinoid transport in a field planted in soybeans. Soils with increased organic carbon leached less thiamethoxam and clothianidin during early growing season leaching peaks; however, at the end of the season, higher organic carbon content only decreased leached mass of clothianidin. The second study was to determine neonicotinoid uptake of different ground covers used as cover crops or edge-of-field buffer strips, as well as the partitioning of thiamethoxam and clothianidin throughout the plants. Ground covers, such as crimson clover, had the highest recovery of applied thiamethoxam, meaning that it may be a good candidate to retain this pesticide in fields. Thiamethoxam and clothianidin concentrations were higher in leaf tissues than in stems or roots, indicating that above-ground biomass removal may be an effective way to reduce neonicotinoid loading in the environment. From these studies, I concluded 1) practices that raise the amount of organic carbon in the soil may help decrease early-season neonicotinoid transport, resulting in lower concentrations in surrounding waterways, and 2) careful selection of plant species, such as crimson clover, may help reduce neonicotinoid transport in the environment, while potentially reducing exposure to beneficial insects.
Master of Science
Pesticides called neonicotinoids are commonly applied to seeds in row crops, such as corn and soybeans, before they are planted. These pesticides are highly soluble in water, which can lead to them exiting fields through runoff or leaching. This thesis is comprised of two studies that examined several potential solutions for decreasing the amount of neonicotinoids available for transport. The first study examined the relationship between organic carbon in the soil and neonicotinoids, and whether this relationship helps to retain neonicotinoids in a soybean field. Soils with high organic carbon content decreased the amount of neonicotinoids exiting the field during early growing season storms; however, at the end of the season, high organic carbon content only decreased losses for one of the pesticides studied. The second study was to determine which of six plant species and two mixes used as cover crops or buffers were the most effective at removing neonicotinoids from soil, as well as where in the plant these neonicotinoids go after uptake. Ground covers, such as crimson clover, had the highest recovery of applied neonicotinoids, meaning they would be good candidates for planting around fields. Ultimately, neonicotinoid accumulation was higher in leaves than in stems or roots, meaning that removing and disposing of leaves in an environmentally safe way could be an effective way to decrease neonicotinoid pollution. From these two studies, I found that 1) increasing organic matter in the soil can stop neonicotinoids from exiting the area it was applied in, and 2) careful consideration of plant species in or around the field may help intercept neonicotinoids before they exit the field.

Spectroscopic characterization of ferric soybean peroxidase with peroxides were studied to determine the ligand coordination and to characterize the structure of the heme active site and its intermediates (ferryl species). The lifetime, chemical reactivity and distinctive colors of the ferryl species (FeIV) formed during the oxidation of peroxidase (FeIII) by peroxides enabled structure, dynamics and reaction mechanisms to be studied. Resonance Raman spectroscopy was used as a means of characterizing the structure of the soybean peroxidase and its intermediates. Excitation in the Soret absorption band at 406.7nm with 2-5mW laser power was used for this study. Resonance Raman spectra in the 200 to 1700 cm-1 region were obtained for the soybean peroxidase. However, the focus of this study was on the vibrational region of the resonance Raman spectra from 900 to 500cm-1 where the FeIV=O stretching frequencies for heme compound II intermediates are expected. Several pH and pD (deuterium substitution) samples of the soybean peroxidase were analyzed using resonance Raman spectroscopy. The vibrational stretching frequencies of the ferryl peroxidases varied with varying pH/pD were observed within the 773–787cm-1 range. From the deuterium experiment, accompanied with changes in the vibrational frequencies of the iron-ligand, a 3cm-1 upshift and intense resonant enhancement of the peaks, we observed the ferryl nature of compound II intermediate for soybean peroxidase. Badger’s rule was used to estimate the bond distances that existed within Fe-O which offers additional insight into the structure of the ferryl species. The estimated bond distance for the soybean peroxidase was significantly less than Fe-O bond distances proposed by X-ray crystallographers for other peroxidases in the same family. Comparing the vibrational frequencies of the ferryl intermediates in soybean peroxidase to that in heme proteins portrayed the effect the protein environment has on the vibrational frequencies.

With many natural landscapes undergoing restoration efforts, there is a growing need for the optimization of direct seeding practices. Seeds planted on wildlands are often consumed by rodents leading to reduced plant establishment. Coating seeds in rodent aversive products may prevent seed predation. We tested ten seed-coating formulations containing products expected to deter rodents, namely: ghost and cayenne pepper powders; essential oils from bergamot, neem, and pine; methyl-nonyl-ketone, anthraquinone, activated carbon, beta-cyclodextrin and a blank coating containing no rodent deterrents to serve as a control treatment. Each treatment was applied to Pseudoroegneria spicata (bluebunch wheatgrass) seeds. These seeds germinated similarly to uncoated control seeds unless the coating contained methyl-nonyl-ketone which reduced germination. Seeds were offered to Ord's kangaroo rats (Dipodomys ordii) that strongly avoided the treatments in favor of uncoated control seeds. Notably, the blank coating, lacking active ingredients, still elicited 99% avoidance. However, these results indicated behavior when alternative food sources are readily available, a scenario rare in nature. To address this, a second feeding experiment was conducted to observe D. ordii's behavior under calorie-restricted conditions. D. ordii were subjected to a fast period and then offered only one treatment. Under these conditions, many subjects chose to consume coated seeds, but to a lesser degree than subjects offered control seeds. Seeds coated in ghost pepper, neem oil, and activated carbon reduced consumption by 47-50%. Given these lab results, we would expect these seed-coatings to increase the establishment of native seeds following the direct seeding of wildlands by deterring rodent seed-predation.

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The use of polymers in soybean seeds has been accomplished with the purpose of incorporating products like insecticides, fungicides, growing substances, minor fertilizers and so on, in order to improve the visual aspect of the seed, to promote smaller operator's intoxication risk and to provide a better seeds' acting and seedlings after sowing. The main objective of this work was to evaluate the recovered seeds' effects in soybeans seed quality lots of high and low germination of the cv. AG 7000. The seed's film coating was accomplished with two commercial marks of polymers, LABORSAN ® , and LANXESS ® , in doses of 2 and 3,5 ml for each kg with and without mixture of the fungicide Carbendazim + Thiram (firewalk ® ). The seeds' quality evalutions, were measured by the germination test, germination in sand and accelerated aging. The use of polymers in soybean seeds provides seeds with good appearance and coloration and can be applied to differentiate the seed from the commercial grain. The fungicide and the polymers do not affect the physiological quality of soybean seed. The results of the polymers and fungicide were superior in the test of accelerated aging, showing higher germination in relation to the check treatment.
O uso de polímeros em sementes de soja vem sendo realizado com a finalidade de incorporar produtos fitossanitários, melhorar o aspecto visual da semente, promover menor risco de intoxicação do operador e proporcionar um melhor desempenho de sementes e plântulas após a sua semeadura. O objetivo principal deste trabalho foi avaliar o efeito do recobrimento na qualidade de semente de soja de alta e baixa germinação da cv. AG 7000. O revestimento foi realizado com duas marcas comerciais de polímeros, LABORSAN ® , e LANXESS ® , nas doses de 2 e 3,5 mL para cada kg de semente com e sem mistura do fungicida Carbendazim + Thiram (firewalk ® ). As avaliações da qualidade das sementes foram realizadas por meio do teste de germinação, germinação em substrato de areia e envelhecimento acelerado. O uso de polímeros na semente de soja proporciona sementes com boa aparência e coloração, podendo ser aplicado para diferenciar a semente do grão comercial. O fungicida e o polímero não prejudicam a qualidade fisiológica da semente de soja. Os resultados do polímero e fungicida foram superiores no teste de envelhecimento acelerado, apresentando maior percentual de germinação em relação à testemunha.

Planting native species after a major disturbance is a critical tool land managers use to stabilize soils, restore ecosystem processes, and prevent weed invasion. However, within the sagebrush steppe and other arid and semi-arid environments the percentage of sown seeds that produce an adult plant is remarkably low. Applying fertilizers at the time of planting may improve native plant establishment by increasing the ability of the seedlings to cope with environmental stresses. However, traditional fertilizer applications are often economically infeasible and may be counterproductive by encouraging weed invasion. Seed coating technology allows for the efficient application of fertilizers within the microsite of the seeded species. The objective of our research was to determine the optimal rate of fertilizer to apply to the seed to improve seedling emergence and plant growth. We applied a phosphorus (P) rich fertilizer (0.13 g P g-1) to bluebunch wheatgrass (Pseudoroegneria spicata (Pursh) Á. Löve) seeds in a rotary coater at rates ranging from 0 to 50 g of fertilizer 100 g-1 seed. Three separate studies were conducted to test germination, biomass, relative growth rate, and tissue nutrient uptake. Study one showed decreasing root and shoot biomass and increasing time to 50% germination as fertilizer rates increased. Study two showed no difference in relative growth rate between the controls and fertilizer treatments. Study three showed no difference in root and shoot biomass or nutrient concentration between treatments except in the lowest fertilizer treatment (10 g fertilizer 100 g-1 seed), which was significantly lower in root and shoot biomass than all other treatments but had higher P tissue concentrations than all other treatments. Collectively these results showed no evidence that a P fertilizer coating could aid in bluebunch wheatgrass seedling establishment. Because bluebunch wheatgrass and similar late-seral plants have evolved with low nutrient requirements they may not be physiologically capable of handling increased nutrient supply, which may explain the results of our studies. Continued studies and fieldwork need to be performed to evaluate the potential of fertilizer seed coatings in restoration efforts.

O restauro ecológico tornou-se imprescindível devido à tendência crescente do uso do solo e constitui um objectivo particularmente desafiador na bacia do Mediterrâneo. As seed balls são uma técnica de restauro pouco estudada cientificamente, particularmente em climas áridos. Pretendeu-se testar o potencial germinativo em seed balls produzidas com diferentes percentagens de argila negra (25%-100%), uma argila com elevado teor de matéria orgânica considerada um desperdício da indústria das cerâmicas, em contexto mediterrânico. Avaliou-se a germinação de seis espécies com sementes de volumes diferentes (pequeno, médio e grande) em três regimes de rega (seco, intermédio e húmido). Sementes pequenas e médias germinaram melhor com 25% de argila negra e sementes grandes germinaram melhor com 50-75% de argila negra. As seed balls podem ser usadas em clima mediterrânico e reaproveitando a argila negra de barreiros portugueses. O ajustamento do tamanho das seed balls à dimensão das sementes deverá constituir o próximo passo; Abstract: Ecological restoration has become essential due to the growing trend in land use and is a particularly challenging goal in the Mediterranean basin. Seed balls are a restoration technique that hasn’t been scientifically studied, particularly in arid climates. It was intended to test the germinative potential in seed balls produced with different percentages of black clay (25% -100%), a clay with high content of organic matter considered a waste in ceramics industry, in Mediterranean context. The germination of six species with seeds of different volumes (small, medium and large) was evaluated in three irrigation regimes (dry, intermediate and wet). Small and medium seeds germinated better with 25% black clay and large seeds with 50-75% black clay. Seed balls can be used in a Mediterranean climate and reusing the black clay of Portuguese clay. Adjusting the size of seed balls to the size of the seeds should be the next step.

O tratamento de sementes pode ser uma importante técnica para o fornecimento de micronutrientes na cultura do milho (Zea mays L.), sendo capaz de promover um melhor estabelecimento da cultura no campo. Solos contendo níveis insuficientes de zinco e de cobre para as plantas são frequentes em grande parte das regiões agrícolas do Brasil e do mundo. Deste modo, o fornecimento destes elementos via sementes pode ser uma alternativa viável e eficaz para produtores de milho. Este trabalho teve como objetivo avaliar diferentes tratamentos de sementes de milho contendo Zn e Cu, considerando aspectos relacionados à qualidade fisiológica das sementes e à eficiência nutricional. Para tal, foram utilizados quatro lotes do híbrido 2B688Hx, apresentando diferenças quanto ao tamanho e vigor das sementes. Os tratamentos foram compostos por diferentes dosagens e combinações de suspensões líquidas contendo óxido de Zn e carbonato de Cu, fornecidos juntos ou separadamente. Os lotes foram avaliados pelo teor de água das sementes, germinação e teste de frio em cinco épocas: 0, 30, 60, 180 e 360 dias. Nas três primeiras épocas, também foram realizados os testes de emergência de plântulas, velocidade de emergência de plântulas e análises do crescimento de raiz por meio do software SVIS®. O desenvolvimento inicial das plantas foi avaliado pela altura, área foliar e massa seca de raiz e de parte aérea. Os dados de massa seca associados aos teores de Zn e de Cu nos tecidos permitiram calcular as eficiências de absorção, transporte e utilização dos mesmos. A qualidade fisiológica de sementes de milho tratadas com Zn e Cu, isoladamente ou associados, não é afetada ao longo de doze meses de armazenamento; por outro lado, o Cu utilizado isoladamente causa fitotoxicidade quando a avaliação é realizada tendo o papel como substrato, afetando principalmente o desenvolvimento radicular das plântulas. O tratamento de sementes com zinco e cobre se constitui em alternativa viável e eficaz para o fornecimento destes elementos para as plantas de milho.
Seed treatment is a potential tool for supplying micronutrients on maize crop (Zea mays L.), enabling a better plant stand establishment in the field. Soils presenting insufficient levels of zinc and copper to plants are common in various agricultural regions throughout Brazil and the world. Thus, the supply of such elements via seeds can be viable and effective for maize crop. This study aimed to evaluate different maize seed treatments containing Zn and Cu, related to the effects on seeds physiological quality and nutritional efficiency. Thus, four seeds lots of the corn hybrid 2B688Hx, differing in size and vigor, were used for this study. The treatments were composed of liquid suspensions containing Zn oxide and Cu carbonate, applied together or separately at different dosages. The lots were evaluated by seed moisture, germination and cold test in five periods: 0, 30, 60, 180 and 360 days. Seedling emergence, seedling emergence speed and image analysis of root growth (software SVIS®) were also performed in the first three periods. The plants development was assessed by height, leaf area and dry weight of roots and shoots. The efficiencies of absorption, transport and utilization were calculated with the data of seedlings dry weight and tissues content of Zn and Cu. The physiological quality of maize seeds is not affected by the treatments containing Zn and Cu, together or separated, during the twelve-month storage period; on the other hand, the treatments containing only Cu caused phytotoxicity on paper-based tests, affecting mainly the seedlings root development. Seed treatment with zinc and copper is a viable and effective approach for supplying these elements to maize plants.

Fusarium oxysporum M12-4A fungus is being evaluated for the biocontrol of Striga hermonthica, a parasitic weed of African cereal crops. The production of M12-4A inoculum was assessed in four Malian villages using local technology and substrates. A delivery system using arabic gum to temporarily glue inoculum powder onto the crop seed was tested. In controlled conditions, coating of sorghum seeds with arabic gum and inoculum powder did not affect seed germination or inoculum viability. However, one week at 40°C significantly decreased the viability of the inoculum by 31%. Fungus growth and chlamydospore germination were also reduced by temperatures of 34 and 36°C. M12-4A was susceptible to the fungicide thiram (ED50 = 38.5mug). Field trials were conducted in Mali to evaluate the large-scale efficacy of the seed coating technology. F. oxysporum M12-4A was detected from some S. hermonthica tissue and soil samples using specific primers and Real Time PCR.

The use of coated seed to establish crops is not a novel practice. Seed coatings have been used on small seeded crops to improve the handling ability by making the seed unit larger and heavier. Producers can therefore calibrate their sowing equipment more efficiently and wind will not cause as much drift at sowing. Seed coating can have an added benefit for leguminous crops if the symbiotic inoculant (Rhizobium) is added to the coating. This saves the producer time and allows peace of mind that inoculation was done by trained professionals. Other than the inoculation, there are some other constituents in the seed coating that can have benefits to the plant. It can, however, be theorized that added nutrients or pesticides will be beneficial to the plants only if these nutrients are deficient in the growth medium or when pests are present. This study evaluated the effect of seed coating on the life stages of germination, emergence and survival, seedling growth and ultimate yield of mature lucerne (Medicago sativa L.) plants, comparing the results with non-coated seed. Two cultivars were used in the evaluation, SA Standard and SuperCuf, to determine if the effects would be similar, or would genetic differences between the cultivar play a significant role. These life stages (germination, emergence and seedling growth) were chosen due to the importance of these stages to the success of establishment. Fast and uniform germination will result in a uniform stand with strong competition against weed infestation. The effect of growth medium on the emergence of seedlings and the interaction between the seed coating and the growth medium was important to determine to identify limitations in the use of seed coating. Changes in the growth of seedlings in terms of some physio-morphological characteristics will assist in identifying parameters influenced by the coating. It was, however, essential to not only do these trials under ideal agricultural conditions, but to identify if similar results would be obtained from stressed conditions, such as salinity, which is a growing concern for crop production areas. The question of whether seed coating will influence the ultimate production of the crop could then be answered. It was found that the method in which germination is tested can have a significant outcome for the results obtained. When the Jacobsen apparatus was compared with the use of petri dishes, using specification according to ISTA, it was found that the water movement in the Jacobsen apparatus overcomes concentrated nutrient conditions, especially for SuperCuf. Under saline conditions the coated SA Standard seed had higher germination than the non-coated seed, therefore overcoming inhibitions imposed by the salinity. It is clear that the coating influences germination of lucerne and the interaction with the seed environment is significant. It is also clear that the genetic differences between cultivars are significant and results should not be applied across all lucerne cultivars. When the emergence percentage had been determined in different growth media, namely a commercial growth media, a sandy loam soil and silica medium, it was found that the emergence was influenced by the media. Even though the emergence of seedlings are mostly determined by the nutrients in the cotyledons, some growing conditions did cause lower emergence for non-coated SA Standard seeds and was overcome by the use of coated seed. When the growing conditions were manipulated with saline irrigation it was found that coated SuperCuf had a higher emergence % than the non-coated treatments when irrigated with the 750 μS.cm-1 water. From the data collected from this trial, it can be concluded that, even though the use of seed coating does not always influence the emergence of lucerne seedlings, seed coating does have an influence on the emergence, but it is dependent on the growth medium quality in terms of nutrient composition and salinity. Similar to the germination trial, the genetic influence of the different cultivars was noticeable. To determine the differences caused by seed coating to the physio-morphological characteristics (stem height, leaf area etc.) of lucerne, a pot trial was conducted using different irrigation treatments, municipal water (180 μS.cm-1), 500 and 750 μS.cm-1 water, created with NaCl. It was found that the physio-morphological characteristics were highly correlated, i.e. the stem height, leaf area, number of leaves and dry matter production changed in relation to each other. There were, however, differences in this correlation coated and non-coated seed treatments, when irrigated with 500 μS.cm-1 water. For the seedlings grown from coated seed, the correlation between shoot dry matter yield and the other parameters were low, while the seedlings growth from non-coated seed, leaf area was not correlated with the other parameters. It was concluded that the tolerance mechanism for salinity for plants irrigated with 500 μS.cm-1 water, caused more differences than the other water treatments. Taking into consideration that coating influences the germination and emergence of lucerne and that the two cultivars react differently to the seed coating, the yields obtained from field trials could then be interpreted if differences were observed. Three field trials were established, namely a trial established in autumn (established in 2009) and second trial established in spring (established in 2010) which were sown at 25 kg.ha-1, while a third trial established spring (established in 2010) was sown at 5 different sowing densities, namely 80%, 90%, 100%, 110% and 120% of recommended sowing density (25 kg.ha-1). It was found that the pasture stands established with SA Standard, did not show many differences between the coated and non-coated seed treatments and were mostly restricted to the second growing season, where the non-coated seed treatments had significantly higher dry matter yield than the coated seed treatments. Stands established with SuperCuf, displayed more variation between the seed treatments and the non-coated seed treatments had higher yields in the first season. It was, however, found that the stands established with coated SuperCuf seed had lower stem: leaf ratio’s, indicating that a better quality fodder can be produced from coated seed. The data from the sowing density trial showed very little difference between the yields of the stands established with coated and non-coated SA Standard seed. Differences were, however, observed between seed treatments at 90% and 120% of the recommended sowing density, where the stands established with non-coated seed had higher yields than the stands established with coated seed. It can be concluded that under these trial conditions, the use of coated seed had very little influence on the yield of the lucerne stands. The observed differences suggest that the lucerne growth under these few conditions, the stands established from non-coated seed had better yield, but the stands established from coated seed had better quality. It is, however, more likely that there will be no differences between the seed treatments. Data from the sowing density trial also led to the conclusion that stands established at 20% less seed will not result in lower yields if the stand establishment is successful. The similarity between the seed treatments and the sowing densities suggests that the number of plants per area were the same, caused by seedling mortality during the high growth rate in the early growing stage, or the morphological characteristics, such as number of stems per plant and number of leaves per stem, adapted to result in similar yields and quality.
Dissertation (MSc Agric)--University of Pretoria, 2013.
gm2014
Plant Production and Soil Science
unrestricted

Seed germination during unhospitable environmental conditions can be a major barrier to direct seeding efforts in dryland systems. In the sagebrush steppe, Artemisia tridentata Nutt. ssp. wyomingensis and Artemisia arbuscula are important shrub species that are being used in restoration, but seeding success is highly sporadic due to inter-annual and intra-seasonal weather variability. Altering and expanding the period of germination, as a form of bet-hedging, may improve plant establishment. Our objective was to determine if we could expand the period of germination using plant growth regulators (PGRs) applied in a conglomerated seed coating treatment. In a laboratory study, the seed was either left untreated, conglomerated separately with two concentrations of a germination inhibitor, abscisic acid (ABA), or with two different germination promoters, gibberellic acid (GA3) and 1-Aminocyclopropane carboxylic acid (ACC), a precursor to ethylene. Seeds were incubated in a loam soil at five constant temperatures (5-25 C) for approximately three months. Results indicate that seed treatments with PGRs can delay or speed germination. The greatest response to the seed treatments was observed at 5 C. For example, at this temperature PGRs delayed the time for 25% of the seeds to germinate by a maximum of 35 and 21 d and decreased this time by 5 and 25 d for A. t. ssp. Wyomingensis and A. arbuscula, respectively. Field studies are needed to determine if the bet-hedging strategy developed in this study will increase the likelihood that some seeds will germinate during periods that are more favorable for plant establishment.

In the seed processing industry, rotary batch seed coaters are widely used for providing a protective coating layer to the seeds consisting of various ingredients including fertilisers and crop protection chemicals. Seed motion and mixing are important in ensuring uniform coating; hence the focus of this work is to address the mixing efficiency and coating uniformity of corn seeds in a rotary batch seed mixer. In the present study, the Discrete Element Method (DEM) is used to analyse the motion and coating uniformity of the seeds. A comprehensive study has been carried out addressing the influence of the shape of corn seeds for accurately simulating their flow in the mixer using two commonly used techniques: (i) manipulation of coefficient of rolling friction of spherical particles, and (ii) clumping multiple spheres. Both methods were successful in simulating the flow of seeds in the mixer, however the former method is found to be an empirical approach rather than predictive. A coating model is used for predicting the coating uniformity of corn seeds in the mixer. Effect of various process parameters on variation of coating mass among the seeds is investigated. For the seed mixer, the baffle clearance gap, baffle geometry and position of the atomiser disc were found to be the key influential process parameters affecting the coating uniformity of corn seeds. Other process parameters such as the base rotational speed, baffle angle, width and curvature had less effects on coating variability. A study has also been carried out on tailoring the existing methods of measuring the extent of breakage of particles for seeds. Four breakage criteria were proposed and assessed for consideration of mass of broken seeds, and the most suitable methods are suggested. The simulations developed here are generic and can be applied to a wide range of coating processes, such as particle and tablet coating. The proposed methodology for measuring the extent of breakage of corn seeds can also be used for other types of seeds.

The primary impacts of mining on the environment include the deterioration of soil properties and the loss of vegetation cover and density, often leading to increased erosion. In order to encumber further degeneration of such ecosystems and all subsequent other negative environmental impacts, active rehabilitation practices are often implemented. Active rehabilitation involves the introduction of species by different re–seeding (re–vegetation) methodologies. A higher vegetation cover and density is needed to increase soil quality, combat erosion and contribute to species richness, diversity and ground cover. Several Acts regarding environmental legislation and the conservation of the natural resource in South Africa are used to ensure that sustainable development, rehabilitation and effective environmental management of disturbed areas are enforced. Legislation therefore provides a measure to prevent pollution and ecological degradation, promotes conservation, secure ecologically sustainable development and the use of natural resources, while promoting justifiable economic and social development. Legislation also enforces and regulates the remediation of disturbed ecosystems, such as the rehabilitation of mine tailing areas. Some of this legislation mentioned above is described in the thesis. Species selected for the compilation of seed mixtures for re–seeding and re–vegetation purposes should comply with the standards determined by the regional biodiversity framework where the disturbed area is situated. Only seed of species with non–invasive potential, that are adapted to the specific environmental conditions and have specific genetic traits, should be included in the seed mixture for rehabilitation. Since seed from local ecotype species are often not available, seed companies use seed from especially grass species that might be adapted to the environmental conditions and type of disturbance or degradation to help remediate the poor soil conditions and improve the vegetation cover. The problem is that if the morphological and physiological aspects of the seed type have not been researched properly, it may lead to poor germination and establishment results when used for the rehabilitation of certain degraded and disturbed areas, such as rangelands or mine tailings. Advance Seed Company tries to enhance seed by adding a coating around the caryopsis (grass seed) for better germination and establishment rates. Such seeds are then referred to as “enhanced” or “coated” seed. The term “seed” will be used throughout the dissertation to describe the whole, intact caryopsis (e.g. Anthephora pubescens). The coatings normally refer to the physical enhancements of the seeds by the application of a water–soluble lime–based coating, which may contain nutrients, fungicides, pesticides and other polymers. This study focused on the evaluation of the germination– and establishment rates in four soil types (growth mediums), as well as the activity of three growth enzymes on coated seed of three grass species, namely Anthephora pubescens, Cynodon dactylon and Panicum maximum. Advanced Seed Company provided the seeds for the three selected grass species that were coated with their newly developed certified formulae. Experimental trails were carried out in the laboratory and greenhouses (controlled conditions) at the North West University and in the field (uncontrolled conditions) at the four locations representing the different soil types, namely the clayey and sandy soils at Taaibosbult near Potchefstroom and the platinum (alkaline growth medium) and gold mine tailings (acidic growth medium) near Rustenburg and Stilfontein respectively. Detailed soil analysis was carried out by certified soil laboratories in Potchefstroom and seed purity, viability and quality determined by the Plant Protection Institute in Pretoria. The results from the greenhouse and the field trials differed significantly for all seed types (coated and uncoated) of the three grass species in the four soil types. The germination and establishment rates in both the greenhouse (controlled conditions) and field (uncontrolled conditions) trials were overall very low. The latter can also be ascribed to the competition with other weed species that were present in the soil seed bank before re–seeding, as well as the predation by ants and guinea fowls in especially the field trials of the sandy and clayey soils. Due to the absence of competition in the field trials on the mine tailings, the germination and establishment rates were higher for most grass species. The quality of the seed batches as supplied by Advance Seed Company was not very good. Although the purity was high, many dead seeds were found, especially for Panicum maximum. The germination and establishment rates of Antephora pubescens of the uncoated seed was higher in the sandy, platinum and gold mine tailings soil types in both the uncontrolled field and controlled greenhouse trials and low for both seed types (coated and uncoated) in the clayey soils. Cynodon dactylon had higher germination and establishment rates for especially the gold mine tailings soil in the field trials for both seed types, as well as the sandy soils under controlled conditions in the greenhouse. Both rates were lower in the sand– and clayey soils field trials. The germination rates for Panicum maximum for both seed types were similar for the clay and sandy soil types, but very low in the soils from the mine tailings, especially under controlled conditions in the greenhouse trials. The germination and establishment rates for both seed types of this species were however much higher in the field trials at both the gold and platinum mine tailings, mainly due to the absence of competition. No results for Panicum maximum were obtained from the field trials on the clay soils due to management and maintenance problems. The peroxidise enzyme activity was higher in the coated seed of Antephora pubescens, but lower in both seed types of Cynodon dactylon and Panicum maximum. The alpha amylase enzyme activity was high in the coated seed of Antephora pubescens and both seed types of Panicum maximum, but low in both seed types of Cynodon dactylon. The activity of the lipoxygenase enzyme was higher in all the coated seed of all three grass species that were used in this study. It also appears as if the storage period played a significant role in the germination of the species, especially after and during the seed coating process, as it had a negative effect on the physiology of the seed. In all species, a higher rate of gaseous exchange was observed in the uncoated seed types. However, the water content of the seed types differed between the seed types. Depending on the size and the genetic characteristics of the species, the longevity of the enzyme proteins differed. This is especially observed in the enzyme activity of three enzymes tested, i.e. lipoxygenase, peroxidase and alpha–amylase. The germination rate only improved shortly after being coated and then declined steadily. The germination capacity therefore depends on the length of the storage period. The genetic adaptation of the different species coincided with the four soil types. It is therefore recommended that only species that are adapted to a certain soil type is used in rehabilitation and if the seed is coated, it should be sown shortly after the coating process and not be stored for long periods. It is also recommended to first treat the area with herbicide before any re–seeding takes place, especially if low concentrations of seeds are used.
Thesis (M.Sc. (Environmental Sciences))--North-West University, Potchefstroom Campus, 2012.

Resumo: Devido à importância da cultura do amendoim na região de Jaboticabal e à necessidade de incremento em sua tecnologia de produção, o objetivo do presente trabalho foi avaliar a possibilidade de utilizar a técnica de peliculização em sementes dessa cultura. Foram realizados três ensaios: a) em laboratório, sobre o efeito do tratamento na germinação e vigor de sementes de amendoim, b) em casa de vegetação, sobre a eficiência do tratamento na germinação de sementes em solo infestado com Rhizoctonia solani e c) ensaio em campo, sobre a influência do tratamento na produção da cultura. Foram utilizados dois lotes de sementes de amendoim, da cultivar Runner IAC 886, de alto e baixo vigor. As sementes receberam os seguintes tratamentos: testemunha, polímero Laborsan® (2,0 mL.kg-1 sementes), fungicida Fludioxonil (Maxin XL) - (1,5 mL.kg-1 sementes) revestido com o polímero Laborsan® (2,0 mL.kg-1 sementes) e fungicida Fludioxonil (Maxin XL) - (1,5 mL.kg-1 sementes). O nível de vigor das sementes teve efeito em todas as avaliações realizadas. O polímero utilizado neste trabalho não afetou o potencial fisiológico das sementes de amendoim, nem a eficiência do fungicida testado, mostrando-se uma técnica promissora, porém, deve ser utilizado somente em conjunto com fungicidas por não controlar patógenos de solo.
Abstract: Due to the importance of the peanut culture in Jaboticabal region and to the necessity of increase its production technology, the objective of the present work was to evaluate the possibility of to utilize the film-coating technique in this culture seeds. It was realized three assays: a) in laboratory relating to the effect of the treatment on peanut seeds germination and vigor, b) in greenhouse relating to seeds germination in infested soil with Rhizoctonia solani and c) in the field assay relating to the influence of treatment on culture production. It was utilized two peanut seed lots of Runner IAC 886 cultivar with high and low vigor. Seeds received the following treatments: control, Laborsan® film-coating (2,0 mL.kg-1 seeds), fungicide Fludioxonil (Maxin XL) - (1,5 mL.kg-1 seeds) recovered with the Laborsan® film-coating (2,0 mL.kg-1 seeds) and fungicide Fludioxonil (Maxin XL) - (1,5 mL.kg-1 seeds). Seeds vigor level had effect in all evaluations. The film-coating used in this work did not affect peanut seeds physiological potential and either the fungicide efficiency, showing a promising technique, however, it must had utilized only with fungicide because it does not control soil pathogens.
Orientadora: Rita de Cassia Panizzi
Coorientador: Rubens Sader
Banca: Margarida Fumiko Ito
Banca: Nilvanira Donizete Tebaldi
Banca: Margarete Camargo
Banca: Adriana Zanin Kronka
Doutor

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Devido à importância da cultura do amendoim na região de Jaboticabal e à necessidade de incremento em sua tecnologia de produção, o objetivo do presente trabalho foi avaliar a possibilidade de utilizar a técnica de peliculização em sementes dessa cultura. Foram realizados três ensaios: a) em laboratório, sobre o efeito do tratamento na germinação e vigor de sementes de amendoim, b) em casa de vegetação, sobre a eficiência do tratamento na germinação de sementes em solo infestado com Rhizoctonia solani e c) ensaio em campo, sobre a influência do tratamento na produção da cultura. Foram utilizados dois lotes de sementes de amendoim, da cultivar Runner IAC 886, de alto e baixo vigor. As sementes receberam os seguintes tratamentos: testemunha, polímero Laborsan® (2,0 mL.kg-1 sementes), fungicida Fludioxonil (Maxin XL) – (1,5 mL.kg-1 sementes) revestido com o polímero Laborsan® (2,0 mL.kg-1 sementes) e fungicida Fludioxonil (Maxin XL) – (1,5 mL.kg-1 sementes). O nível de vigor das sementes teve efeito em todas as avaliações realizadas. O polímero utilizado neste trabalho não afetou o potencial fisiológico das sementes de amendoim, nem a eficiência do fungicida testado, mostrando-se uma técnica promissora, porém, deve ser utilizado somente em conjunto com fungicidas por não controlar patógenos de solo.
Due to the importance of the peanut culture in Jaboticabal region and to the necessity of increase its production technology, the objective of the present work was to evaluate the possibility of to utilize the film-coating technique in this culture seeds. It was realized three assays: a) in laboratory relating to the effect of the treatment on peanut seeds germination and vigor, b) in greenhouse relating to seeds germination in infested soil with Rhizoctonia solani and c) in the field assay relating to the influence of treatment on culture production. It was utilized two peanut seed lots of Runner IAC 886 cultivar with high and low vigor. Seeds received the following treatments: control, Laborsan® film-coating (2,0 mL.kg-1 seeds), fungicide Fludioxonil (Maxin XL) – (1,5 mL.kg-1 seeds) recovered with the Laborsan® film-coating (2,0 mL.kg-1 seeds) and fungicide Fludioxonil (Maxin XL) – (1,5 mL.kg-1 seeds). Seeds vigor level had effect in all evaluations. The film-coating used in this work did not affect peanut seeds physiological potential and either the fungicide efficiency, showing a promising technique, however, it must had utilized only with fungicide because it does not control soil pathogens.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Cucumis melo is one of the most important horticultural species representing the family Cucurbitaceae, moreover, it is the leader fruit concerning value and volume of exportation in Brazil. As in other cultures, both physiological and health quality of seeds used in the crop establishment are critical to ensure an appropriate population of plants and with high quality and productivity. Treatment of seeds is employed in order to protect them against pathogens, as well as, to accelerate and uniform their germination. Thus, this study aims to evaluate the physiological and health quality of melon seeds, cv. Gaúcho Redondo‟, treated with chemical fungicides, biocontrol agents, micronutrients and polymer. Application rates followed recommendations described by manufacturers. Evaluation of physiological traits was undertaken by means of germination, seedlings length, cold storage, germination at low temperatures, greenhouse emergence and emergence speed index tests. Health quality tests, by the other hand, were determined by Blotter test , transmission and pathogenicity of Fusarium spp. isolated from melon seeds. Treatments with micronutrients, purely or combined with polymer coating, incremented in seed germination, as well as, the emergence and the emergence speed index. Trichoderma spp. also provided a significant increase in the first count and germination. The fungicide Captan® acted efficiently on Fusarium spp. present in the seeds, though it had not been totally eradicated. This pathogen associated with melon seeds did not affect the germination process of them.
Cucumis melo é uma das principais hortaliças representantes da família Cucurbitaceae, além disso, é a fruta líder em valor e volume de exportação no Brasil. Como em todas as culturas, a qualidade fisiológica e sanitária das sementes utilizadas na implantação da lavoura é fundamental para garantir uma população adequada de plantas e com elevada qualidade e produtividade. O tratamento de sementes é utilizado para promover a proteção das sementes contra patógenos causadores de doenças e proporcionar uma germinação mais rápida e uniforme. Dessa forma, o presente trabalho teve como objetivo avaliar a qualidade fisiológica e sanitária das sementes de melão, cultivar Gaúcho Redondo, após tratamento das mesmas com fungicidas químicos, agentes de biocontrole, micronutrientes e polímero. As doses de aplicação dos produtos seguiram as recomendações dos fabricantes e as avaliações da qualidade fisiológica das sementes foram realizadas através do teste de germinação, comprimento de plântulas, teste de frio, germinação a baixas temperaturas, emergência em casa de vegetação e índice de velocidade de emergência. Já a qualidade sanitária foi determinada pelo teste de sanidade, transmissão e patogenicidade de isolados de Fusarium spp. obtidos das sementes de melão. Os tratamentos com micronutrientes, isolados ou com recobrimento de polímero, promoveram incremento na germinação das sementes, assim como na emergência e no índice de velocidade de emergência. Trichoderma spp. também proporcionou aumento significativo na primeira contagem e na germinação. O fungicida Captan® atuou de forma eficiente no controle de Fusarium spp. presente nas sementes, embora não tenha erradicado totalmente. Este patógeno, associado às sementes de melão, não interferiu no processo germinativo das mesmas.

Seeds sown in the fall to restore sagebrush (Artemisia spp.) steppe plant communities could experience high mortality when they germinate and seedlings freeze during the winter. Delaying germination until the risk of frost is past could increase seedling survival. We evaluated the use of abscisic acid (ABA) to delay germination of Elymus elymoides, Pseudoroegneria spicata, and Linum perenne. The following treatments were applied: uncoated seed, seed coated with ABA at 2.2, 4.4, 8.8, 13.2, and 17.6 g of active ingredient kg-1 of seed, and seed coated with no ABA. The influence of seed treatments on germination were tested at five different incubation temperatures (5-25°C). The lowest application rate of ABA had no significant influence on germination percentage but higher application rates showed a decline. All concentrations of ABA tested delayed germination, especially at low incubation temperatures. For example, the time required for 50% of the seeds to germinate at 5°C was increased with the use of the lowest ABA application rate by 56, 61, and 14 days, for E. elymoides, P. spicata, and L. perenne, respectively. Quadratic thermal accumulation regression models were developed for each species and treatment to predict progress toward germination. For the two grasses, models had sufficient accuracy (R2 = 0.61- 0.97) to predict germination timing using field seedbed temperatures. Equations for L. perenne were less accurate (R2 = 0.03-0.70). Use of these models will allow testing whether ABA will delay germination sufficiently to avoid winter frost periods and provide the basis for future field tests.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Seed treatment with paclobutrazol should be enhanced and coating technologies, such as film coating can be applied uniformly and promising to fix this regulator in the seed coat without allowing a contact damaging the embryo. Thus, the objective of this study was to evaluate the technical feasibility of the film coating tomato seeds with paclobutrazol on seed physiological potential and the implications on the growth of seedlings. The research was carried out in the Laboratory of the “Setor de Horticultura” and at nursery seedling of “Setor de Manejo Integrado de Pragas” of “Escola de Agronomia e Engenharia de Alimentos” from March to October 2012. Three experiments were conducted. First, to define the best dosage of polymer coating, the treatments were arranged in a 2 x 4 factorial, with two cultivars (Santa Clara and Kada Gigante) and four concentrations of polymer Disc AG Red L-203® (0, 50, 100 and 150 mL kg-1 seed). In the second, with the polymer concentration established, the potential adhesive film coating for seed treatment with paclobutrazol was determined through a 2 x 4 factorial arrangement, presence or absence of the coating polymer Disc AG Red L-203® (0 and 150 ml kg-1 seed) and four paclobutrazol concentration PBZ (0, 35, 70 and 105 mg L-1). In the third, the tomato seed conditioning with PBZ (50 mg L-1) and coating polymer Disc AG Red L-203® (150 mL kg-1 seed) were evaluated. The film coating promotes negative effects on germination of cultivar Santa Clara. The cultivate Kada Gigante obtained a superior performance to Santa Clara as the emergence of seedlings. The use of hydrophilic polymer (150 ml kg-1 seed) increased 4% seedling emergence compared to control. The PBZ resulted in reductions in 27% germination, 8% seedling emergence, 19% seedling height, 20% leaf area and in increase in the detection of chlorophyll of 24%, compared to control. Imbibition of seeds with PBZ, even with the presence of the polymer coating, harmed the speed of germination and seedling emergence. In conclusion, the effect of film coating on the germination of tomato seeds depends on the cultivar. The seed physiological potential can increased by the use of polymer coating, although it does not occur for the production of seedlings. PBZ is effective in seedling growth control, but affect the germination and seed vigor. The film coating as a vehicle for fixation of paclobutrazol is not indicated due to maintenance of reduced seedling emergence.
O tratamento de sementes com paclobutrazol deve ser aprimorado e tecnologias de recobrimento, como a peliculização, podem ser promissoras para aplicar uniformemente fixar este regulador no tegumento das sementes sem permitir um contato prejudicial ao embrião. Assim, o objetivo do presente trabalho consistiu em avaliar a viabilidade técnica da peliculização de sementes de tomate associada ao paclobutrazol sob o comportamento fisiológico de sementes e as implicações no crescimento de mudas. A pesquisa foi conduzida no Laboratório do Setor de Horticultura e em casa de vegetação do Setor de Manejo Integrado de Pragas da Escola de Agronomia e Engenharia de Alimentos, de março a outubro de 2012. Foram conduzidos três experimentos. Primeiramente, os tratamentos foram dispostos em esquema fatorial 2 x 4, sendo duas cultivares (Santa Clara e Kada Gigante) e quatro concentrações do polímero Disco AG Red L-203® (0, 50, 100 e 150 mL kg-1 de semente) para definição da melhor dose de polímero de revestimento. No segundo, com a dose de polímero estabelecida, o potencial adesivo da peliculização para o tratamento de sementes com paclobutrazol foi determinado por meio de um arranjo fatorial 2 x 4, sendo presença ou ausência do polímero de revestimento Disco AG Red L-203® (0 e 150 mL kg-1 semente) e quatro concentrações de paclobutrazol - PBZ (0, 35, 70 e 105 mg L-1). No terceiro, o condicionamento de sementes de tomate com PBZ (50 mg L-1) e polímero de revestimento Disco AG Red L-203® (150 mL kg-1 de semente) foram avaliados. A peliculização prejudicou a germinação de sementes da cultivar Santa Clara. A cultivar Kada Gigante obteve um desempenho superior a Santa Clara quanto à emergência de plântulas. O uso de polímero hidrofílico (150 mL kg-1 de semente) aumentou 4% a emergência de plântulas, em relação ao controle. O PBZ propiciou reduções de 27% na germinação, 8% na emergência de plântulas, 19% na altura de parte aérea, 20% na área foliar e aumento de 24% na detecção de clorofila, em relação ao controle. A embebição de sementes com PBZ, mesmo com a presença do polímero de revestimento, prejudicou a velocidade de germinação e a emergência de plântulas. Conclui-se que o efeito da peliculização na germinação de sementes de tomate depende da cultivar utilizada. O potencial fisiológico pode ser incrementado pelo uso de polímeros de revestimento, sendo que isto não ocorre para a produção de mudas. O PBZ é eficiente no condicionamento da altura de mudas, mas prejudica a germinação e o vigor de sementes. A peliculização como veículo para fixação do PBZ não é indicada devido à manutenção da redução da emergência de plântulas.

Public land management agencies, conservation organizations, and landowners are interested in expanding the diversity of plant species used in rangeland restoration seedings. While the restoration of native grasses and shrubs in the Great Basin has become increasingly successful, restoration of native forbs continues to be problematic. In the Great Basin, soil water availability and soil fungal pathogens are thought to limit to restoration success. During the course of two years, we conducted two field experiments at three sites in the Great Basin that spanned a latitudinal gradient encompassing different precipitation and temperature patterns. In the first experiment, we evaluated two treatments for enhancing native forb restoration – snow fences and N-sulate fabric. In addition, we tested whether multiple fungicide and hydrophobic seed coatings could reduce seed and seedling mortality from soil fungal pathogens. To quantify the effectiveness of treatments, we tracked the fate of sown seeds over four life stages: germination, seedling emergence, establishment, and second-year survival. We found that snow fences and N-sulate fabric had varying degrees of success for increasing seedling emergence or establishment but ultimately did not increase second-year survival. Seed coatings increased seedling emergence but did not increase establishment or second-year survival. In the second experiment, we replicated the first experiment and also measured soil water availability to better understand how snow fences and N-sulate fabric alter soil water availability, and if differences in soil water availability can explain restoration outcomes. While we found that our treatments can increase soil water availability, increased soil water did not consistently result in better restoration outcomes. Snow fences did not benefit any life stage at any site while N-sulate fabric had positive and negative effects on forb restoration depending on the site. Seed coatings increased seedling emergence and establishment at all sites, warranting further research with other forb species. Results from both experiments provide insights for developing new treatments and techniques that can improve native forb restoration in the Great Basin and similar semiarid systems.

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Universidade Federal de Sao Carlos
In order to minimize the effects caused by the development of Brazil, such as the suppression of riparian forest, one has searched for tree species that have the characteristics needed for the recovery of degraded areas. Given this, studies focus on higher plants of encapsulated wild fruits, especially the Mabea fistulifera Mart. Considering that M. fistulifera reproduces through embryonic units that need to be treated, this study aimed to evaluate the drying of wild fruits with explosive dehiscence and the coating "in natura" seed with gel mixture via coating pan, as well as evaluating the tolerance of embryos related to the immediate effects of the processes. Thus, the experimental procedure consisted of the collection of capsular fruits and extraction of seeds of fruit by drying so were analyzed drying methods via radiation, natural convection, forced convection and coating pan. It was considered for the drying methods analysis the opening fruit speed and seed vigor. Thus, all processes allowed physiological recovery of embryos, but the extraction method via pan promoted the highest opening speed of the fruits. Once performed the extraction, the seeds were separated from the inert material obtaining pure batches of seeds. There were also characterizations of size, shape and specific mass obtaining the results (0,78±0,05) cm, (0,67±0,04) cm and (0,59±0,04) cm for Dmax, Dmédio and Dmim, respectively, form factor (0,75±0,01), specific mass of (1,20±0,01) g/cm³ and apparent mass of (0,82±0,01) g/cm³. Analyzes were also made for chemical seed yielding (82,93±0,11)% of dry matter (19,03±0,78)% crude protein, (1,18±0,11) g/kg calcium (0,65±0,03) g/kg magnesium (0,58±0,04) g/kg phosphorus (13,45±0,33) g/kg potassium (0,70±0,03) g/kg of sulfur. The process of coating seeds, through reaction between sodium alginate gel and calcium chloride salt at different angles of inclination and rotation speed of the coating pan, was also analyzed. Thus, it was found that to achieve the coating of the particles it was necessary to prepare the particle surface by chemical scarification, in order to increase the surface roughness of the seed, followed by rehydration with saturated calcium chloride. This way, it was found that the angle of 25° and speed of 25 rpm generate the greatest quantity of mass adhered on seeds. In addition, tests were performed to verify the efficiency of the coating process, and with the lowest angle set in experimental design was found higher values of efficiency. In tests of particle growth was evaluated that the process time was approximately 8 seconds. Finally, the analysis and processing of data obtained through statistical techniques and equations from literature were performed. In this way, the results contributed to improvements in drying processes of wild fruits and the coating of seeds of the pioneer species M. fistulífera.
A fim de minimizar os efeitos causados pelo desenvolvimento do Brasil, tal como, a supressão da Mata Ciliar, buscam-se espécies arbóreas que tenham as características necessárias para a recuperação de áreas degradadas. Diante disto, estudam-se plantas superiores de frutos encapsulados silvestres, das quais se destaca a Mabea fistulífera Mart.. Tendo em vista que a M. fistulífera se reproduz através de unidades embrionárias que precisam ser tratadas, este estudo teve como objetivo avaliar a secagem de frutos silvestres com deiscência explosiva para extração das sementes e do recobrimento das sementes com mistura gel via drageadora, bem como a avaliação da tolerância dos embriões em relação aos efeitos imediatos dos processos. Assim, o procedimento experimental consistiu na coleta dos frutos capsulares e extração das sementes através da secagem dos frutos, de modo que foram analisados os métodos de secagem via radiação solar, convecção natural, convecção forçada e via secagem em drageadora. Considerou-se para a análise dos métodos de secagem a velocidade de abertura dos frutos e qualidade fisiológica das sementes. Assim sendo, verificou-se que todos os métodos permitiram a recomposição fisiológica dos embriões, porém a secagem via drageadora ocorreu com menor tempo de processo em relação às demais técnicas. Uma vez realizada a extração das sementes, estas foram separadas dos materiais inertes obtendo-se lotes puros de sementes. Realizaram-se também as caracterizações de tamanho, forma e massa específica obtendo-se os resultados de (0,78±0,05) cm, (0,67±0,04) cm e (0,59±0,04) cm para os Dmáx, Dmédio e Dmim, respectivamente, fator de forma de (0,075±0,01), massa específica real de (1,20±0,01) g/cm³ e massa específica aparente de (0,82±0,01) g/cm³. Foram feitas também análises para caracterização química das sementes obtendo-se (82,93±0,11)% de matéria seca, (19,03±,078)% de proteína bruta, (1,18±0,11) g/kg de cálcio, (0,65±0,03) g/kg de magnésio, (0,58±0,04) g/kg de fósforo, (13,45±0,33) g/kg de potássio e (0,70±0,03) g/kg de enxofre. Analisou-se também o processo de recobrimento das sementes via reação entre o gel alginato de sódio e o sal cloreto de cálcio em diferentes ângulos de inclinação e velocidade de rotação da panela rotatória (drageadeira). Verificouse que para realizar o recobrimento das partículas foi necessário preparar a superfície das partículas através de escarificação química, visando ao aumento na rugosidade da superfície das sementes, e posterior reumidificação com solução saturada de cloreto de cálcio. Desta forma, constatou-se que o ângulo de 25° e a velocidade de 25 rpm possibilitaram maior quantidade de massa aderida sobre as sementes. Além disto, realizaram-se testes a fim de verificar a eficiência do processo de recobrimento, sendo que nos níveis mais baixos do planejamento experimental verificaram-se os maiores valores de eficiência. Nos testes de crescimento das partículas avaliou-se o tempo de processo que foi aproximadamente de 8 segundos. Por fim, foi realizada a análise e o tratamento dos dados obtidos, mediante técnicas estatísticas e equações advindas da literatura. Desta forma, com os resultados obtidos colaborou-se para avanços nos processos de secagem dos frutos silvestres e no recobrimento das sementes da espécie pioneira M. fistulífera.

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The present study, we used seeds of wheat, cv Fundacep horizon coated with six doses of aluminum silicate (0, 20, 30, 40, 50 and 60g per 100 kg seed). We conducted two research studies in order to verify the influence of the silicon used by seed, and to evaluate the physiological performance and yield components. In the first paper we studied the behavior of the physiological quality of seeds coated with aluminum silicate. The second was carried out the experiment evaluating the absorption by the plants and silicon influence on the rate of chlorophyll and the components of yield and quality physiological seed. The results showed that aluminum silicate improves the physiological quality of seeds have been subjected to stress and yield of wheat plants grown from seeds coated with aluminum silicate.
No presente trabalho utilizaram-se sementes de trigo, cultivar Fundacep Horizonte recobertas com seis doses de silicato de alumínio (0, 20, 30, 40, 50 e 60 g por 100 kg de sementes). Foram conduzidos dois trabalhos de pesquisa no intuito de verificar a influência do silício empregado via semente, bem como avaliar o desempenho fisiológico e os componentes de rendimento. No primeiro trabalho estudou-se o comportamento da qualidade fisiológica das sementes recobertas com silicato de alumínio. No segundo foi realizado a condução do experimento avaliando-se a absorção do silício pelas plantas e a influência no índice de clorofila, bem como nos componentes de rendimento e a qualidade fisiológica das sementes produzidas. Os resultados mostraram que o silicato de alumínio melhora a qualidade fisiológica das sementes se submetidas a estresse e o rendimento das plantas de trigo oriundas de sementes recobertas com silicato de alumínio.

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This research aimed to evaluate the effect of silicon on cotton, through variables agronomic, physiological, yield and fiber quality and seeds produced. The experiments were conducted in 2012 and 2013. In the first year of cultivation, were evaluated five levels of Si: 0, 1000, 2000, 3000 and 4000 kg Si ha-1, applied to soil, 0, 45, 60, 135 and 180 kg Si ha-1 foliar, and 0, 100, 200, 300 and 400 g kg seed-1, applied through seed coating. In the second year, were evaluated five levels: 0, 45, 60, 135 and 180 kg Si ha-1 and 0, 2000, 4000, 6000 and 8000 kg Si ha-1, applied via foliar and soil, respectively. The silicon source used is aluminum silicate. Evaluations were performed at 25, 50, 75 and 100 days from emergence (DAE). The results of the experiments allow to conclude that aluminum silicate applied by seed coating does not interfere in the physiological characteristics of cotton. However, when applied by foliar and soil, increases the chlorophyll index and reduces the diameter of the stem of cotton plants. In relation to yield, the number of seeds per fruit and number of fruit and seeds per plant were negatively affected with the increase of Si foliar applied. The silicon improves some physical characteristics of the fiber such as reflectance, short fiber index, degree of yellowing and micronaire index. Regarding the quality of seeds produced, increases the length of roots and shoots of seedlings, positively influences the weight of a thousand seeds by seed coating and soil and can increase productivity.
Esta pesquisa teve a finalidade de avaliar o efeito do silício no algodoeiro, por meio das variáveis agronômicas, fisiológicas, rendimento e qualidade da fibra e sementes produzidas. Os experimentos foram realizados em 2012 e 2013. No primeiro ano de cultivo, avaliaram-se cinco doses de Si: 0, 1000, 2000, 3000 e 4000 Kg de Si ha-1, aplicadas via solo; 0, 45, 60, 135 e 180 Kg de Si ha-1, via foliar; e 0, 100, 200, 300 e 400 g Kg de sementes-1, aplicadas via recobrimento de sementes. No segundo ano, avaliaram-se cinco doses: 0, 45, 60, 135 e 180 Kg de Si ha-1 e 0, 2000, 4000, 6000 e 8000 Kg de Si ha-1, aplicadas via foliar e solo, respectivamente. A fonte de silício utilizada foi o silicato de alumínio. As avaliações foram realizadas aos 25, 50, 75 e 100 dias após a emergência (DAE). Os resultados obtidos dos experimentos permitem concluir que, o silicato de alumínio aplicado via recobrimento de sementes, não interfere nas características fisiológicas do algodoeiro. Porém, quando aplicado via foliar e no solo, aumenta o índice de clorofila e reduz o diâmetro do caule de plantas de algodão. Em relação ao rendimento, o número de sementes por capulho e o número de capulhos e sementes por planta, foram afetados, negativamente, com o aumento das doses de Si aplicadas via foliar. As doses de silício melhoram algumas características físicas da fibra como a reflectância, índice de fibras curtas, grau de amarelamento e índice micronaire. Em relação à qualidade das sementes produzidas, aumenta o comprimento da raiz e parte aérea de plântulas, influencia positivamente o peso de mil sementes, via recobrimento de sementes e solo, podendo incrementar a produtividade.

Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
The search for more productive seeds and with better transport and storage conditions has developed the interest of companies and researchers. In this section, nanotechnology, in particular, polymer / clay nanocomposites has proved to be an excellent alternative. By means of these nanomaterials it is possible to transport assets that allow the plant to better growth, productivity and germination rates, through the transport of fertilizers, agrochemicals or even essential micronutrients. The aim of this work was to synthesize and study nanocomposites polymer / clay; poly (hydroxyethyl methacrylate), pure laponite (pHEMA / Lap) and enriched with manganese micronutrients (pHEMA / LapMn). These materials aim to provide water and concomitantly provide nutrients to the seeds. The best formulation for the samples, amounts of polymer and clay was studied, and from this the micronutrient was incorporated into the formulation. The materials were characterized by absorption spectroscopy in the infrared region (FTIR), X-ray diffractometry (XRD) and thermogravimetry (TG). In addition, the water uptake capacity of the samples was evaluated. TG results showed an increase in thermal stability due to the interaction of the polymer chain with the clay. The XRD study showed that pure Lap and Lap Mn presented similar basal spacing to that found in the literature and that the nanocomposite had an exfoliated structure of the materials. The observation of the degree of swelling of the samples showed that the nanocomposites showed a capacity of water absorption 10% higher than the pure hydrogel. The seed coating affected the germination rate of the seeds, showing an optimization of this process.
A busca por sementes mais produtivas e com melhores condições de transporte e armazenamento tem desenvolvido o interesse de empresas e pesquisadores. Nesta vertente, a nanotecnologia, em especial, os nanocompósitos polímero/argila tem se mostrado uma excelente alternativa. Por meio destes nanomateriais é possível transportar ativos que possibilitem a planta melhor crescimento, produtividade e taxas de germinação, por meio do transporte de fertilizantes, agroquímicos ou até micronutrientes essenciais. Neste trabalho buscou-se sintetizar e estudar nanocompósitos polímero/argila; poli(metacrilato de hidroxietila) (pHEMA), laponita pura (pHEMA/Lap) e enriquecida com micronutrientes manganês (pHEMA/LapMn). Estes materiais tem por objetivo fornecer água e concomitantemente fornecer nutrientes para as sementes. Estudou-se qual a melhor formulação para as amostras, quantidades de polímero e de argila e a partir desta incorporou-se o micronutriente a formulação. Os materiais foram caracterizados por espectroscopia de absorção na região do infravermelho (FTIR), difratometria de raios X (DRX) e termogravimetria (TG). Além disso, a capacidade de absorção de água das amostras foi avaliada. Houve aumento da estabilidade térmica decorrente da interação da cadeia polimérica com a argila. O estudo por DRX mostrou que a Lap pura e a Lap Mn apresentaram espaçamento basal similar ao encontrado na literatura e que o nanocompósito apresentou estrutura esfoliada dos materiais. A observação do grau de intumescimento das amostras mostrou que os nanocompósitos apresentaram uma capacidade de absorção de água 10% superior à do hidrogel puro. O revestimento das sementes prejudicou a taxa de germinação das mesmas mostrando-se necessário uma otimização deste processo.
São Cristóvão, SE

Cette étude a pour objectif la recherche d’huiles et de composés bioactifs dans des graines provenant de la région semi-aride à aride « Regueb » située au centre de la Tunisie. Plusieurs graines sont riches en huiles principalement composées d'acides gras classiques. Des teneurs élevées en acide pétrosélinique, un acide gras inhabituel, ont été détectées chez les espèces appartenant à la famille des Apiaceae, en particulier P. major et P. saxifraga. Les graines de d’Ap. graveolens, An. graveolens, P. saxifraga et L. sativum sont à la fois riches en huiles et en composés phénoliques fonctionnels. L’accumulation de ces composés dans les graines en développement a été étudiée pour P. major, P. saxifraga et L. sativum. Certaines graines contiennent également des huiles essentielles ayant un pouvoir antibactérien comme celles de P. saxifraga, Ap. graveolens et C. sativum qui sont riches en anéthol, dillapiole et linalol. L’huile essentielle des graines de P. saxifraga (PSEO) a été, pour la première fois, testée dans un enrobage comestible à base d’alginate de sodium pour la conservation du fromage frais. Une évaluation de sa toxicité chez les souris a permis la détermination de la plage de doses sans effet nocif. L’enrobage comestible d'alginate de sodium enrichi en PSEO a amélioré la conservation du fromage frais "Sicilien de Bèja" en permettant de préserver le pH et la couleur, de diminuer la péroxydation lipidique et d’améliorer la stabilité bactérienne. L'analyse sensorielle a montré une forte appréciation du fromage enrobé en présence de PSEO
The aim of this study is to identify bioactive oils and compounds in seeds from the semi-arid to arid region of "Regueb" in central Tunisia. Several species contained high amounts of oil mainly composed of classic fatty acids. High amounts of petroselinic acid, an unusual fatty acid, have been detected in species of the family Apiaceae, in particular P. major and P. saxifraga. The seeds ofAP. graveolens, An. graveolens, P. saxifraga and L. sativum were rich in oil and functional phenolic compounds. The accumulation of these compounds in growing seeds has been studied for P. major, P. saxifraga and L. sativum. Several seed contained essential oils with antibacterial properties such as those of P. saxifraga, AP. graveolens and C. sativum, which contained anethole, dillapiole and linalool. The essential oil of P. saxifraga seeds (PSEO) was, for the first time, tested in an edible coating based on sodium alginate for the preservation of fresh cheese. An evaluation of its toxicity in the mice allowed the determination of the dose range without any harmful effect. The edible coating of sodium alginate enriched with PSEO has improved the preservation of the fresh Sicilian cheese by preserving pH and color, reducing lipid peroxidation and improving bacterial stability. Sensory analysis showed a strong appreciation of coated cheese in presence of PSEO

碩士
國立臺灣大學
農藝學研究所
87
The major purposes of this thesis are to set up a laboratory seed coating system, to test the operating factors of seed coating, and to establish an effective seed coating process. The major body of the preliminary model is a fluidized bed. The air is supplied to the fluidized bed by a blower, is monitored by a flowmeter, and is pre-heated by a heater. The temperature of the fluidized bed is also measured and controlled by temperature controller that was inserted in the bed. Coating slurry is sent to the nozzle by a microtube pump and is sprayed from the two-phase nozzle that was equipped in the fluidized bed. The better operating factors of the preliminary seed coating model are: a nozzle height set at 16.5cm above the distributor, an air velocity triple of the minimum fluidization velocity, a bed temperature of 45 ℃ at the round spray nozzle, and a slurry feeding rate of 15ml/min at 2kg/cm air pressure. Different binders and coating materials are tested with the preliminary seed coating model. Methylcellulose (1%)、carboxymethylcellulose (1%、2%、3%、3.5%、4%)、gum arabic (9%、11%、13%、15%) and polyvinyl alcohol (3%、5%、7%、9%) used as binders in 5 minutes coating treatments do not affect rapeseed germination. The coated size of the rapeseed increased with the binder concentration. Different binders, based of the same concentration, cause different coating rate in descending order: carboxymethylcellulose > polyvinyl alcohol > gum arabic. Coating material tests show that, slurry solutions of calcinated diatomaceous earth or clay can be sprayed easily from the nozzle, while slurry solutions of non-calcinated diatomaceous earth and active carbon slurry deposit in the tube of microtube pump, and can not be distributed to the nozzle. Although clay can be sprayed smoothly into the bed, wet quenching occurred in the bed due to the high water holding capacity of the clay. These results indicate that both the physical and the chemical properties of the coating material are very important in an applicable coating procedure. The drawbacks of the preliminary seed-coating model are 1, dust cumulated on the nozzle and held back the slurry atomization; 2, the pressure of the wriggle microtube pump is not uniformly applied on the slurry, resulting in the different atomized particles; 3, The interval between the nozzle and the distributor cannot be adjusted according to the practical requires. A revised seed coating model is designed to improved the performance of seed pelleting. Spouted bed is used instead of the fluidized bed. The nozzle is composed in the base of the cone without a distributor. The cone angle is determined according to the nozzle spray angle. The revised seed coating model is tested by the rapeseed. It is found that the problems of the preliminary seed coating model are solved successfully. Coating procedure operates continuously for up to 44 minutes without interruption. The coated seed size increased linearly with the treating time. Pelleted seed size of the cabbage increased with the coating time. The ratio of thickness to length and/or width increased with coating time, resulting in more roundness of the sweet pepper seeds, which indicates superior capability of the revised model to that of the preliminary one. A coating layer of 2.57mm in thickness do not retard the germination of sweet pepper seed, but a thickness of 1.72mm reduces the percentage germination of the cabbage. Washing away the pelleting material from the seeds is effective in recovering the decreased germination of the cabbage seed. The result suggests that, due to the hydrophilic property of diatomaceous earth and polyvinyl alcohol, the coating layer of the pelleted seeds can be mushy after imbibing and prevents O2 from entering the seed. The cabbage seeds may also be subjected to accelerated aging more due to their higher oil content compared with that of the sweet pepper seeds.

Tese no âmbito do Doutoramento em Biociências, ramo de especialização em Biotecnologia, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e tecnologia da Universidade de Coimbra.
The interest in plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal (AM) fungi for agricultural purposes (e.g. enhancement of crop yield and nutrition, promotion of plants resilience to abiotic stress) is rising. Yet, large-scale applications of these microbes have been hampered by the lack of data on their field performance and the feasibility of the inoculation methods, especially in the case of AM fungi. Seed coating, a technique in which seeds are covered with minor amounts of exogenous materials (including microbial inoculants), is a potential tool to deliver microbes at large-scale. This technique has been gaining attention in the agricultural sector. A literature review revealed that seed coating has been applied to more than 50 plant species (e.g. wheat, tomato, maize, melon, bean, clover), including seeds with different characteristics (dimensions, forms, textures). Mostly studied for the application of various species of PGPR (especially from the genera Pseudomonas and Bacillus), seed coating is not so frequently explored for inoculation of AM fungi or microbial consortia. The improvement of crop productivity and protection of plants against pathogens have been the main focus of research on microbial seed coating, while a smaller portion has been aimed at enhancing crops resistance to abiotic stresses. One of the main goals of this PhD thesis was to evaluate seed coating as a deliver system for the inocula of AM fungi and PGPR. Overall, seed coating allowed the application of minor amounts of AM fungi and PGPR to the seeds of three selected agricultural crops: maize, cowpea and chickpea. Further, by comparing inoculation of AM fungi through direct soil inoculation (conventional) with seed coating, similar AM root colonization was obtained despite a reduction in the amount of applied inocula. Contrary to AM fungi, the presence of PGPR coated on the seeds could not be confirmed in the rhizosphere and roots of the inoculated crops. It is well known that both AM fungi and PGPR have the ability to improve soil fertility and enhance plant nutrition, which can bring benefits for plant growth and development. By increasing nutrient availability and nutrient use efficiency, these plant beneficial microbes (PBM) can assist farmers to reduce their dependence on chemical fertilizers. The results obtained in this thesis showed that coating seeds with PGPR and AM fungi had a significant impact on plant shoot nutrient concentrations under different fertilization regimes. For instance, maize seeds coated with AM fungi (Rhizophagus irregularis) increased shoot nutrient concentration (nitrogen, phosphorus, potassium, magnesium and zinc), comparing with non-inoculated plants. Nutrient contents on maize shoot were boosted by R. irregularis inoculation, particularly in the treatments where fertilization was reduced or absent. On the contrary, maize coated with PGPR (Pseudomonas fluorescens) presented most of the nutritional increments when full fertilization was applied. Nevertheless, in both inoculation treatments, despite the nutrient enhancements, no improvement in plant biomass was obtained. These results confirm that PBM can increase plant nutrient uptake. PGPR and AM fungi are known to confer drought resistance to plants. Coating seeds with PGPR (Pseudomonas putida) showed a general positive influence in the plant productivity, especially under moderated water deficit. Seed coating with AM fungi (R. irregularis singly or in consortia with P. putida) promoted nutrient uptake, leaf pigment contents and gas exchange parameters of cowpea, yet mostly when plants where under no water deficit. Mainly, these results emphasized the importance of selecting the PBM that better potentiate plant resilience to abiotic stresses, in order to obtain the best benefits from the inoculation. Field experiments are essential to validate the benefits of microbial seed coating and its feasibility for large-scale applications. A comparison between chickpea coated with a single AM fungal isolate of R. irregularis and multiple isolates of the same fungal species under greenhouse and field conditions showed that plants inoculated with multiple AM fungal isolates performed better (e.g. higher biomass, increased grain yield) than those inoculated with a single AM isolate. Seed coating proved to be an appropriate tool to deliver AM fungi with benefits for chickpea plants at both experimental scales, but particularly relevant under field conditions. The mixture of multiple R. irregularis isolates was also used in consortium with Pseudomonas libanensis for coating cowpea seeds. This treatment significantly improved crop productivity in comparison with non-inoculated plants and plants inoculated with R. irregularis single-isolate + P. libanensis. The results showed improvements in grain lipid content, soil physicochemical properties (pH and soil organic matter), and crop yield under low-input agricultural systems. AM fungi and PGPR should be selected for microbial seed coating formulation according to their affinity with the host crop, growing conditions (e.g. soil properties) and farming practice (e.g. irrigation and fertilization), in order to obtain economical profits. This thesis is a contribution to the knowledge on microbial seed coating and highlights the potential of seed coating as a microbial delivery tool and the benefits of its use in different agricultural conditions. Microbial seed coating can be of great use for sustainable agricultural systems. Yet, in order to allow its large-scale application as a cost-effective technique for PGPR and AM fungi inoculation, further development is necessary.
O interesse em rizobactérias promotoras de crescimento de plantas (RPCP) e fungos arbusculares micorrízicos (FAM) para fins agrícolas (e.g. melhoramento do valor nutricional e rendimento de culturas, promoção de resiliência de plantas a factores abióticos) tem vindo a aumentar. Contudo, a aplicação em larga escala destes microrganismos tem sido dificultada pela escassez de dados sobre a performance destes em campo e viabilidade dos métodos de inoculação, em particular, no caso dos FAM. O revestimento de sementes, uma técnica que consiste em cobrir sementes com pequenas quantidades de materiais exógenos (incluindo inoculantes microbianos), representa uma potencial ferramenta para inocular microrganismos em grande escala. O revestimento de sementes tem vindo a ganhar importância no sector agrícola. Segundo a revisão da literatura realizada nesta tese, o revestimento de sementes foi usado em mais de 50 espécies de plantas (e.g. trigo, tomate, milho, melão, feijão, trevo), abrangendo sementes com diferentes características (dimensões, formas, texturas). Principalmente estudado para aplicação de várias espécies de RPCP (em particular do género Pseudomonas e Bacillus), o revestimento de sementes não tem sido tão frequentemente usado para inoculação dos FAM ou consórcios microbianos. O aumento da produtividade e proteção de culturas agrícolas contra agentes patogénicos têm sido o principal foco da investigação sobre revestimento de sementes com microrganismos benéficos. Por outro lado, os estudos referentes ao melhoramento da resistência de plantas a stresses abióticos através do revestimento de sementes têm sido consideravelmente menores. Um dos principais objectivos desta tese foi avaliar a técnica de revestimento de sementes como método de inoculação para FAM e RPCP. De uma forma geral, o revestimento de sementes permitiu a aplicação de pequenas quantidades de FAM e RPCP em sementes de três culturas: milho, feijão-frade e grão-de-bico. Uma comparação entre inoculação directa no solo (convencional) e revestimento de sementes com FAM, mostrou que, apesar da redução na quantidade de inoculo aplicado, a eficiência do fungo na colonização nas raízes da planta alvo foi similar. Contrariamente aos FAM, a presença de RPCP na rizosfera e raízes das culturas selecionadas não foi confirmada. É de conhecimento geral que tanto os FAM como RPCP têm a capacidade de melhorar a fertilidade do solo e o estado nutricional das plantas, o que pode ser de grande proveito para o desenvolvimento e crescimento destas. Através do aumento da disponibilidade ou eficiência de utilização dos nutrientes, estes microrganismos promotores de crescimento de plantas (MPCP) podem ajudar os agricultores a reduzir a dependência de fertilizantes sintéticos. De acordo com os resultados obtidos nesta tese, sementes revestidas com RPCP e FAM tiveram um impacto significativo no estado nutricional das plantas quando submetidas a diferentes regimes de fertilização. Por exemplo, sementes de milho revestidas com FAM (Rhizophagus irregularis) apresentaram um aumento significativo na concentração de nutrientes na parte área (azoto, fósforo, potássio, magnésio e zinco), quando comparado com plantas não inoculadas. A concentração de nutrientes, na parte área do milho, foi estimulada pela inoculação de R. irregularis, em particular, em tratamentos com fertilização reduzida ou ausente. Pelo contrário, o aumento na concentração de nutrientes em milho revestido com RPCP (Pseudomonas fluorescens) foi superior quando plena fertilização foi aplicada. Contudo, apesar do incremento nutricional, em geral, não se verificaram aumentos a nível da biomassa da planta em ambas as inoculações. Estes resultados confirmam que os inoculantes podem influenciar de forma positiva a absorção de nutrientes pelas plantas. RPCP e FAM são conhecidos por conferir resistência a plantas sobre stress hídrico. O revestimento de sementes com RPCP (Pseudomonas putida) mostrou, em geral, um efeito benéfico na productividade do feijão-frade, em especial, quando submetido a deficit hídrico moderado. Por sua vez, o revestimento de sementes com FAM (R. irregularis) individual ou em consórcio com P. putida promoveu a absorção de nutrientes pela planta, o conteúdo de pigmentos nas folhas e parâmetros de troca gasosa, contudo, na sua maioria na ausência de stress hidríco. Estes resultados realçam a importância de selecionar os MPCP que melhor fomentem a resiliência das plantas a stresses abióticos, a fim de tirar melhor partido da inoculação. Experiências de campo são indispensáveis para corroborar os benefícios do revestimento de sementes com microrganismos e a viabilidade para aplicações em grande escala. Uma comparação entre grão-de-bico revestido com um único isolado de R. irregularis e com uma mistura de vários isolados de R. irregularis, em estufa e em campo, mostrou que as plantas revestidas com múltiplos isolados tiveram um melhor desempenho (e.g. incremento na biomassa e na produção de grão). O revestimento de sementes mostrou ser uma ferramenta adequada para a inoculação de FAM com vantagens para a produção de grão-de-bico em ambas as escalas experimentais, em particular, para as condições de campo. A mesma mistura de isolados de R. irregularis foi usada em consórcio com Pseudomonas libanensis para revestir sementes de feijão-frade. Este tratamento aumentou significativamente a produtividade da cultura em comparação com plantas não inoculadas e plantas inoculadas com único tipo de isolados de R. irregularis + P. libanensis. Os resultados revelaram melhoramentos no conteúdo lipídico das sementes, nas propriedades físico-químicas do solo (pH e matéria orgânica do solo) e no rendimento da cultura, num sistema agrícola de baixo input. FAM e RPCP devem ser selecionadas de acordo com a sua afinidade com a planta alvo, condições de cultivo (e.g. propriedades do solo) e práticas agrícolas (e.g. irrigação, fertilização), de forma a obter lucros. Esta tese contribui para aumentar o conhecimento sobre revestimento de sementes com microrganismos, e realça o potencial da técnica como ferramenta de inoculação de FAM e RPCP e os seus benefícios em diferentes condições agrícolas. O revestimento de sementes com microrganismos pode ser de grande interesse para sistemas agrícolas sustentáveis. Contudo, de forma a permitir o uso em larga escala, como um método eficiente para a inoculação de RPCP e FAM, é necessário apostar no seu melhoramento e desenvolvimento.

碩士
國立中興大學
農藝學系
81
The present experiments were designed to evaluate the effect of film coating on germination and emergence responses of sor- ghum cultivars Taichung No.5 and Tainan No.6 using ethyl cellu- lose(EC), polyvinyl pyrrolidone(PVP-40) and sodium carboxymethyl cellulose(CMC) as coating materials. The results indicated that the polymer EC-coating could reduce imbibitional water uptake and imbibitional leaching, decrease oxygen uptake, inhibit amyl- ases activities, and consequently increase the mean emergence time(MET). These results might be linked to the decreased seed coat conductivity in the seeds coated with EC. In contrast, CMC coating increased water absorption, increased seed leakage, en- hanced oxygen uptake and stimulated amylase activity. However, CMC coating didn't affect the MET. Both cultivars responded to coating, similarly. Nevertheless,cultivar Taichung No.5 was more responsive to EC coating,in terms of MET,as compared to cultivar Tainan No.6. This phenomenon seems to be related to the thicker seed coat and lower seed coat conductivityof cultivar Taichung No.5.

碩士
南臺科技大學
光電工程系
105
Light Emitting Diode is the trend of future lighting, high-power LED in the technical breakthroughs, but to completely replace the traditional lighting source, at this stage of the lighting efficiency is slightly inadequate, so that the LED can not replace the traditional lighting source, so LED luminous efficiency Promotion, is one of the keys to the current technological development. In this paper, we focus on improving the efficiency of light extraction of LED to reduce the internal total reflection of the grains as the theoretical basis to achieve the efficiency of LED light extraction. In this study, a nanostructure array was used to achieve the opportunity to reduce the total light reflection. The ZnO seed layer was grown on P-type gallium nitride by spin coating and dip coating. Then, Into the solution to growing the ZnO nanorod. In the experiment, zinc nitrate Zn (NO3) 2 / HMTA was changed at a fixed concentration, oven temperature and time, and then exposed to different temperature and time using a field emission electron microscope (FE-SEM) The Photoluminescence Spectroscopy (PL) was used to measure the light intensity, and the crystal quality was analyzed by X-ray wide-angle diffractometer. The results of the final measurement showed that the parameters of the ZnO nanorod were the best light intensity in the PL, the reaction time was 1 hour and the oven temperature was 80°C. Compared with the unstructured luminescence intensity of the grown nanorod, the highest excitation wavelengths are obtained at 516nm. Therefore, the P-type GaN diodes are grown with this parameter as the column on the surface, The current injection was measured by integrating the ball and found that the growth of the ZnO nanorod GaN diodes was increased by 0.022 V compared to the non-grown nanorod starting voltage at 5 mA current injection 150mA voltage and 0.201V increase compared with the non-grown nanorod LED, 15% increase in the light intensity part and the light emission wavelength of the two elements will be blue with the increase of the injection current caused by the phenomenon, containing ZnO nanorod The blue shift of the bipolar body is smaller than that of the conventional GaN diodes.

碩士
國立虎尾科技大學
生物科技研究所
100
Damping-off is one of the most serious diseases of cabbage seedlings in Taiwan. The disease was caused by two common soilborne pathogens, such as Rhizoctonia solani and Pythium aphanidermatum. The infected seedlings of cabbage could be killed either before or after emerging from the soil. The common symptoms were cankers, brown lesions on stems, or root rot on roots if they can still survive. Therefore, this research tried to study on the effect of seed coating treated by Trichoderma spp. on seed germination, seedling growth and disease incidence of cabbage. The cabbage seeds were coated by using mixture of methyl cellulose and carboxymethyl cellulose as the adhesives, diatomaceous soil as the filler and the spore of Trichoderma spp. as protectant The seed germination, plant growth and disease incidence were detected by bioassay with Rhizoctonia solani and Pythium aphanidermatum in plate medium and greenhouse. The results indicated that Trichoderma spp. could enhance the germination rate in aging seeds of cabbage. The germination rates for untreated seeds, and treated seperatively with Trichoderma virens LN-PA R4-2 and Trichoderma harzianum ET S3-2-3 were 55%, 75% and 68%, respectively. For the dural tests, the result showed that T. virens LN- PA R4-2 and T. harzianum ET S3-2-3 could inhibit seperatively the mycelial growth of R. solani AG-4 and P. aphanidermatum. Furthermore, for plate assay, the results showed that cabbage seeds coated by Trichoderma spp. could reduce considerably the disease incidence of damping-off. In green house test, the results also confirmed that cabbage seeds coated with T. virens LN- PA R4-2 and T. harzianum ET S3-2-3 could significantly reduce the damping-off disease in seeding stage. To get together, the treatment of seed coating of cabbage using by Trichoderma strains as protectant can be used as an alternative method for chemical control of plant diseases.

碩士
國立中興大學
園藝學系所
96
Cabbage seeds are small, smooth, brown, and globular. The seeds of three cabbage cultivars were studied the relationship between seed components and radicle protrusion time. The most appropriate method of assessing seed vigor and the various presowing treatments on the germination of seeds of ‘Autumn King’ were evaluated. Scanning electron microscopy revealed that the outer seed coats of all three cabbage cultivars and the inner seed coats of ‘228’ and ‘Autumn King’ were of the reticulate–foveate type, while the inner seed coat of ‘CA49’ was of the reticulate type. Seeds of the three varieties had different germination periods, with the radicle protrusion time for ‘CA49’, ‘228’, and ‘Autumn King’ being approximately 11, 17, and 25 h, respectively. Seed of ‘228’ absorbed the least water. Among the three cultivars, ‘CA49’ seed contained the highest levels of total soluble sugar and crude fat, ‘228’ contained the highest levels of starch and soluble protein, and ‘Autumn King’ contained the highest level of sinapine. Vigor tests carried out on ‘Autumn King’ cabbage seed reveled that germination performance decreased significantly with increasing aging time. The electrical conductivity of the seed leachate and the levels of soluble carbohydrate, free amino acid, and potassium ion in the leachate from aged seeds were about double that of control seeds. The control seed produced carbon dioxide at a rate significantly higher than that of seed aged 36 h and 48 h 1.2– and 2.7–fold, respectively. The dehydrogenase activity of control seed was significantly higher than that of aged seed. In the tetrazolium test, the completely and the unevenly stained seeds demonstrated a high level of vigor, and these seeds were present at great proportions of the control seed. Sinapine leachate could be used in detecting seed quality among seed lots. The sinapine fluorescent of control and primed seeds was present under UV, while seeds were imbibed for 4–24 h and 1–3 h, respectively. The emergence rate was highly correlated with the values of the vigor tests. At 35°C, the germination percentage of control ‘Autumn King’ seeds, 73.3%, was significantly lower than that of the primed seeds or soaked seeds, with or without a coating, with the germination percentage of the latter ranging from 88.3% to 95.0%. The emergence and normal seedling percentages of seeds subjected to the priming–coating with 0.3% methyl cellulose treatment were significantly higher than those of the control seeds or seeds coated with 0.4% arabic gum. The sinapine leakage index (SLI) and the fluorescent percentage of ungerminated seeds of the priming–soaking– sorting–coating treatments were zero. Following storage for 6 months, the emergence percentage of control, primed, and soaked seeds without coating significantly decreased by more than 3%. The number of mean days to emergence for seeds of the storage seed lot was significantly longer than 4 days. After accelerated aging for 36 h, the germination percentage was significantly lower only in primed seed (8%) compared to primed or soaked seeds coated with 0.3% methyl cellulose. These results indicated that cabbage seed could be treated by priming–soaking–coating to maintain germination quality.

碩士
國立聯合大學
LED光電製程產業專班
100
This work is dedicated to investigate the effects of seed layer on the controlled growth, morphologies, and electrical characteristics of the ZnO nanorod arrays. The seed layers were prepared by RF sputtering (200 W for 30 min) and dip-coating, respectively. For the dip-coating, the seed layer precursor (0.05M) was prepared by mixing zinc acetate-2-hydrate (Zn(CH3COO)2．2H2O) and hexamethylenetetramine (HMTA). For the CBD reaction, the seeded substrates were then immersed into the zinc acetate solution (0.01 M or 0.03 M) to initiate the growth of ZnO nanorods with temperature maintained at 95 °C for 1.5 h, then the ZnO samples received heat treatment at 400 °C for 10 min. The prepared ZnO nanorod arrays have been characterized by SEM and PL analysis, and the sensing properties of liquid ethanol were studied. Experimental results show that seed layer prepared by RF sputtering has denser structure and also leads to better crystal quality as compared to the seed layer by dip-coating. The sensing performance of the ZnO-based sensors against liquid ethanol was investigated using electrical impedance spectroscopy (EIS). For the complex Nyquist plots, the ZnO sensor (seed layer: dip-coating) exhibits much faster response in high concentration condition (99%); however, no significant difference was observed in low concentration (1~10%). Moreover, the n-ZnO/p-NiO heterojunction electrodes composed of different ZnO seed layers were also fabricated, and the electrical properties such as rectifying behavior, rectifying slope, and series resistance were determined.

碩士
義守大學
材料科學與工程學系
104
The purpose of this work is to use a hydrothermal process to synthesize titanium dioxide (TiO2) nano-rods (TNRs) film on 15 mmx15 mm size of fluorine doped tin oxide (FTO) conductive glass as the photo-anodes of dye-sensitized solar cells (DSSCs). A TiO2 seed layer with anatase structure was deposited on a fluorine doped tin oxide (FTO) coated glass substrate by spin coating. 1.75g potassium titanium oxalate (K2TiO(C2O4)2)was added to the mixture solvent of 100mL containing de-ionized (DI) water and diethylene glycol (DEG), and vigorously stirred for 30 min. The hydrothermal synthesis was conducted at 180 °C for 9 h for the growth of the TiO2 nanowire arrays. N719 dyes as well as the iodine ions electrolyte were served as the dye-sensitized solar cell (DSSC) components, and the DSSC devices were analyzed by I-V meters to determine the photo-conversion efficiency. Up to date, the optimal TNRs films revealed the best photo-conversion efficiency of 5.96% under illumination of simulated AM1.5 solar light (100 mWcm−2). In this study, the films synthesized using optimum process parameters with a high specific surface area and well-aligned TNRs morphology can significantly improve the photo-conversion efficiency.

This M. Sc. thesis is based on using of mycoparasitic fungi Trichoderma virens, Clonostachys rosea f. catenulata in biological control against phytopathogenic fungi Sclerotinia sclerotiorum, Rhizoctonia solani, Botrytis cinerea and Fusarium solani. The efficacy of mycoparasitic fungi against pathogens was evaluated in dual cultural tests. The strains of T. virens and C. rosea f. catenulata isolated from soils in the Czech Republic were tested in the experiment. Reference strain was GL 21 fungus T. virens reisolated from commercially available bio-preparation SoilGard and strain C. rosea f. catenulata reisolated from Prestop Mix. All the strains were tested for biological and production properties. All strains are able to colonize the substrate and to suppress the growth and development of pathogens. Strain GL 21 of T. virens was used for seed coating of variety Scirocco in combination with products Guar gum and Carboxymethyl cellulose, which served as a carrier for stick on conidia. After 3 days, the effect of fungus T. virens was evaluated on energy of germination, development of roots of grain. The grain health was determined after 7 days. The fungus T. virens has a positive effect on the grains germination and grain health. During the vegetation the influence of seed coating by T. virens was observed on growth and development of spring wheat. The parameters such as number of plants per m2, tiller numbers, plants health, stand height, number of grains in the spike and thousand grain weight (TGW) were evaluated. During the vegetation the fungus T. virens has positive effect on the plant height.