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Liu, Yongjie, e Fujiang Hou. "Effects of three-dimensional soil heterogeneity on seed germination in controlled experiments". Journal of Plant Ecology 14, n. 1 (19 ottobre 2020): 1–9. http://dx.doi.org/10.1093/jpe/rtaa070.
Testo completoAbstract (sommario):
Abstract Aims Seed germinations react to their local growing conditions, but the impacts of soil heterogeneity on seed germinations are not well known. Methods Effects of three-dimensional soil heterogeneity on seed germinations of grasses species were explored, where two levels of such soil heterogeneity were created via alternatively filling nutrient-poor and nutrient-rich substrate in pot in all directions. Patch sizes of the two heterogeneity levels are around 7.5 and 15 cm, respectively. Fifty seeds of each of the grasses species (Lolium perenne and Elymus nutans) were set either in these heterogeneous soils or in petri dishes with distilled water. Seed germinations of these species were daily recorded. Important Findings We found that pots with smaller patches had relatively lower germination rate, which is consistent with our expectation that shorter distance between nutrient-rich and nutrient-poor patches in pots with smaller patches allows plants to reduce their germination rates and delay their germination, in order to reduce the negative impacts of the strong variation of soil resources in these pots. Our results also revealed that pots with smaller patches yielded more heterogeneous seed germination, i.e. seed germinations highly diverged among these pots. These findings highlight that the realistic three-dimensional design can improve our understanding of seed germination as driven by soil spatial heterogeneity.
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Vrzalová, Jana, e Pavel Knot. "The effect of seed age and treatment by Proradix method on germinability and initial growth of selected meadow grass (Poa pratensis) varieties". Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 59, n. 5 (2011): 309–14. http://dx.doi.org/10.11118/actaun201159050309.
Testo completoAbstract (sommario):
The goal of the study conducted in 2008 and 2010 at the Research Forage Production Station in Vatín was to investigate the influence of seed age and seed treatment by Proradix method on the germination dynamics, total germinating capacity and initial growth rate of selected meadow grass varieties. The testing was carried out in controlled conditions on the germinator. Our results indicate that the age of seed significantly affects both the germination dynamics and the total germinating capacity. On day 7 after the establishment of the trial, a significantly higher germinating capacity was observed in the 4-year old seed (33.3%) as compared with the 2-year old seed (17.4%). Nevertheless, from day 13, higher germination values were recorded in the younger seed and its total achieved germinating capacity was significantly higher too (+7.2%). Interesting was a finding that the older seed of most varieties showed a more readily oncoming germination, which may play a quite important role in some cases namely in meadow grass, which is known by slow initial growth. The older seed exhibited significantly lower values of both above-ground biomass and the biomass of roots. The Proradix method appeared as efficient in boosting the total germinating capacity. It significantly increased germination rate as well as total germinating capacity. At the same time, a positive effect was observed of treatment by this method on the length of both shoot and root parts; the difference was statistically insignificant though.
3
Amaral-Baroli, Adriana, e Massanori Takaki. "Phytochrome controls achene germination in Bidens pilosa L. (Asteraceae) by very low fluence response". Brazilian Archives of Biology and Technology 44, n. 2 (giugno 2001): 121–24. http://dx.doi.org/10.1590/s1516-89132001000200002.
Testo completoAbstract (sommario):
Achene without ornament of the tegument were light insensitive with germination under all tested light conditions. Achene with verrucose ornament of the tegument presented low germination under darkness and high germination under light conditions. By pre-incubation at 36° C for remotion of pre-existing Pfr and by comparison of results of counting of dark germinating achenes at the end of experiment and daily under dim green safe light (0.001mumol m-2 s-1 nm-1) we concluded that germination was controlled by phytochrome through very low fluence response.
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Blumenthal, MJ, SC Aston e CJ Pearson. "Effect of temperature and moisture potential on germination and emergence in Lotus sp". Australian Journal of Agricultural Research 47, n. 7 (1996): 1119. http://dx.doi.org/10.1071/ar9961119.
Testo completoAbstract (sommario):
Two controlled cabinet experiments compared the germination of 6 Lotus genotypes over a range of temperature (0-40�C) and moisture potentials (0 to -1.2 MPa). A field experiment compared the emergence of 5 Lotus genotypes over 18 sowing dates. Lotus cornzculatus cv. Grasslands Goldie. L. uliginosus, Grasslands Maku, G4703, G4704. and cv. Sharnae were included in both the controlled cabinet and field experiments. Lotus suaveolens CPI 35903 was included in the controlled cabinet experiments only and Trifolium repens cv. Haifa was included as a control in the field study. Of the commercially available Lotus cultivars, Grasslands Goldie provides the greatest flexibility in terms of sowing date in coastal New South Wales and could be successfully sown even in late autumn and winter as it had the lowest base temperature for germination and field emergence. G4703, Sharnae, and G4704 had a lower base moisture potential for germination than the other 3 Lotus genotypes but this was not translated to better field emergence. Lotus suaveolens had an extremely low base temperature for germination (l�C) compared with L. uliginosus cv. Grasslands Maku (6.4�C). Hybridisation of this species with both L. corniculatus and L. uliginosus could result in germplasm capable of germinating better at low temperature but still able to maintain the perenniality, rhizomatous habit, and presence of condensed tannin of L. uliginosus.
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Cuena-Lombraña, Alba, Marco Porceddu, Caterina Angela Dettori e Gianluigi Bacchetta. "Gentiana lutea L. subsp. lutea seed germination: natural versus controlled conditions". Botany 94, n. 8 (agosto 2016): 653–59. http://dx.doi.org/10.1139/cjb-2016-0030.
Testo completoAbstract (sommario):
Gentiana lutea L. subsp. lutea is a geophyte that occurs in the central-southern European mountains. We investigated its germination ecophysiology with the main aim of evaluating seed germination behaviour under controlled and natural conditions. Seeds from four natural sites were tested for germination requirements under a range of different temperatures, and by comparing the results with those obtained under both cold stratification at 5 °C and treatment with GA3. We simultaneously carried out germination tests at each collecting site, and soil temperatures were recorded. Our results indicate that germination under controlled conditions is limited by high temperatures (25 °C), below which GA3 has a remarkable effect on germination percentages. Cold stratification did not have an influence on the germination response, thus suggesting that a temperature of 5 °C is not sufficient to break seed dormancy; this result was supported by soil temperatures. Gentiana lutea created a short-term persistent seed bank, and seeds mainly germinated in their first year. The germination under controlled conditions was similar in all accessions, while different responses were found in the field, where a potential influence of the aspect was observed. These findings underscore the importance of understanding germination behaviour in the field to define the real thermal requirements of a taxon.
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Hermesh, R., e S. N. Acharya. "Influence of maternal plant environment and provenance on alpine bluegrass seed germination". Canadian Journal of Plant Science 72, n. 3 (1 luglio 1992): 801–8. http://dx.doi.org/10.4141/cjps92-096.
Testo completoAbstract (sommario):
Adequate restoration of alpine disturbances requires seed material capable of germinating in high proportions and at a rapid rate. Germination of alpine bluegrass (Poa alpina L.) seeds of different provenances and produced under different environmental conditions was compared under uniform conditions of 16/8 h cycles of light/dark and 22/15 °C temperature. Seeds from nursery plots at the Alberta Environmental Centre, Vegreville, germinated in significantly higher proportions and faster than seeds from the same accessions grown in alpine environments. Alpine bluegrass clones grown in controlled environment chambers set at 22/15 °C and 15/8 °C light/dark with a 16-h photoperiod produced seeds with higher rates of germination and greater cumulative germination than seeds produced in an 8/1 °C regime. It is suggested that alpine blue-grass seeds with high germination percentage and rates are best produced under prairie nursery conditions.Key words: Alpine bluegrass, Poa alpina L., seed germination, maternal environment
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Finch-Savage, W. E., e C. I. McQuistan. "Performance of carrot seeds possessing different germination rates within a seed lot". Journal of Agricultural Science 110, n. 1 (febbraio 1988): 93–99. http://dx.doi.org/10.1017/s0021859600079739.
Testo completoAbstract (sommario):
SummaryThe relationship between germination rate within a carrot seed lot and subsequent seedling performance was studied in four seed lots of different viability. Seedling performance was assessed using slope tests conducted under controlled conditions and in the field following fluid drilling under a range of environmental conditions. Germination rate within a seed lot was positively related to vigour measured by slope tests, percentage emergence and seedling weight, and was negatively related to the spread of emergence times (In variance days) and the coefficient of variation (c.v.) of seedling weights. Sowing seeds selected as fast germinating resulted in greater seedling emergence percentages over a range of environmental conditions than when sowing seeds selected as slowly germinating.
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Matthews, S. "Approaches to the indirect evaluation of germination and vigour". Scientia Agricola 55, spe (1998): 62–66. http://dx.doi.org/10.1590/s0103-90161998000500011.
Testo completoAbstract (sommario):
In comparisons of six seed lots of different F1 hybrid cultivars of cauliflower with similarly high laboratory germinations (above 90%) separation in germination was achieved after controlled deterioration (C.D.) at 24% moisture content (m.c.) and 45 0C for 24 hours. This measure of vigour was related to the position of the lots on the seed survival curve and was highly predictive of the longevity of the lots when stored at 15% m.c. and 20 0C for 12 and 16 weeks. When each seed lot was deteriorated at 24% m.c. for increasing times (from 0 to 36 hours) a reduction in the subsequent percentage germination was seen, which, using probit transformed percentages, was significantly and linearly related to the leakage of electrolytes into seed soak water over 24 hours. The case is made for an approach to the indirect evaluation of germination and vigour using C.D. followed by measurements of leakage that could be more discerning and rapid than the present laboratory germination test.
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Marsh, Lurline E., e Mohsen Dkhili. "GERMINATION AND GROWTH OF COWPEA AND PIGEONPEAS AT CONTROLLED LOW TEMPERATURES". HortScience 27, n. 6 (giugno 1992): 682f—682. http://dx.doi.org/10.21273/hortsci.27.6.682f.
Testo completoAbstract (sommario):
Twenty cowpea (Vigna unguiculata) and 10 early maturing pigeonpea (Cajanus cajan) genotypes were grown at 20/10 C, and 17/10 C day/night and 16 hr. photoperiod to assess their germination and growth. At 20/10 C eighteen cowpea genotypes including the line MN13, and the cultivar, Pinkeye Purple Hull commenced germination at 6 days after planting and showed at least 80% germination 21 days later. Generally, genotypes did not differ significantly in germination and seedling growth up to 45 days later. At 17/10 C two of the cowpea genotypes IT 82E-16 and IT 84E-124 attained at least 90% germination within 21 days after planting. Seedling, growth of these genotypes did not differ and plants began to die 70 days after planting. The pigeonpeas at 17/10 C commenced germination at 9-10 days like many of the cowpeas. Most had at least 50% germination and did not differ in shoot elongation and leaf production. All pigeonpeas flowered between 109 and 136 days after planting and produced pods with immature seeds.
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Bauerová, Lucie, Shiferaw Alem Munie, Kateřina Houšková e Hana Habrová. "Germination of Dracaena cinnabari Balf.f. Seeds under Controlled Temperature Conditions". Forests 11, n. 5 (6 maggio 2020): 521. http://dx.doi.org/10.3390/f11050521.
Testo completoAbstract (sommario):
Research highlights: This study is focused on the germination of Dracaena cinnabari seeds in order to discover the possibility of natural and artificial regeneration of this species. Background and Objectives: This study aimed to determine the optimal temperature for D. cinnabari seed germination, e.g., the temperature at which the germination percentage and germination rate (vitality) are the highest. The objectives of this study are to: (1) determine the optimal temperature for the germination of D. cinnabari seeds, (2) compare the suitability of different seed collection methods, and (3) compare the germination parameters of seeds that were collected from different localities. The results of this study will contribute to obtaining the highest number of seedlings from limited seed material for reforestation of the most endangered localities of D. cinnabari species. Materials and methods: Four seed sections were employed. These sections were directly collected from either the fruits of a cut panicle or the ground and were obtained from different localities that differ in altitude. The seeds were tested in a greenhouse while using Petri dishes at three different temperatures—22, 26, and 30 °C—with four replicates of 25 seeds of each section. ANOVA and the t-test were employed for data analysis. Results: The highest germination percentages (GPs) were achieved at 26 °C and 30 °C, which were 84.6% and 82.5%, respectively. The ANOVA and t-test results showed that the germination index (GI) of the species was relatively higher at a temperature of 30 °C relative to that at other temperatures in the study. Although seeds that were collected from the tree achieved a higher GP, the t-test result showed no significant differences in the GI of D. cinnabari seeds that were collected from the ground and from the tree (p > 0.05). Overall, the findings of this study show that temperature has substantial influence on the germination of seeds of D. cinnabari. Therefore, we recommend a temperature of 30 °C to facilitate the germination of D. cinnabari, as it achieved the highest GI at this temperature relative to that at the other temperatures (22 °C, 26 °C) applied in this study.
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Wawrzyniak, Mikołaj K., Juan Manuel Ley-López, Joanna Kijowska-Oberc, Paweł Chmielarz e Ewelina Ratajczak. "Effects of spermidine on germination of Salix spp. after storage under controlled conditions". Dendrobiology 87 (2 giugno 2022): 137–48. http://dx.doi.org/10.12657/denbio.087.010.
Testo completoAbstract (sommario):
Willows produce fast germinating and short-lived seeds, difficult to store in the long-term under controlled conditions. The aim of this study was to examine the feasibility of storage of three Salix spp. at controlled temperatures (3°, −10°, −196 °C). We also analyzed the effect of spermidine (Spd) as an antioxidant factor in desiccated seeds. Collected seeds were either desiccated or hydrated to obtain 10 levels of moisture content (between app. 4% and 2%) and subjected to storage at temperatures 3°, −10°, or −196 °C (liquid nitrogen; LN). After two months, seeds were germinated on the light at 20 °C. Seeds desiccated below a safe range of moisture content were further tested and germinated on filter paper with additions of 0.25 mM Spd solution. After 7 days seedlings were examined for hydrogen peroxide content (H2O2) and total antioxidant capacity (TAC). Fresh seeds of three Salix species: Persian willow (S. aegyptiaca L.), heartleaf willow (S. cordata Michx.) and crack willow (S. ×fragilis L.) were successfully stored at temperature −10° and −196 °C for two months. After cryopreservation seed of S. aegyptiaca, S. cordata, and S. ×fragilis germinated without viability loss in moisture content ranging from 4.4–15.9%, 6.4–18.5%, and 7.1–11.5% respectively. The addition of Spd during germination of desiccated seed did not affect germination capacity. However, seedlings of S. aegyptiaca had lower hydrogen peroxide content in comparison with control (germination on water). Seedlings of S. cordata showed an increase in hydrogen peroxide content in control after storing in LN. In seedlings of Crack willow Spd increased hydrogen peroxide content. Seeds of tested species differ in response to storage conditions. Salix seeds can be stored successfully for two months at −10° or −196 °C without losing viability in the safe range of moisture content. Storing at 3 °C can be used for storage in the narrower range of seeds’ moisture content, however, seedlings stored at this temperature produce a higher level of reactive oxygen species. Germinating seeds in Spd did not increase their germination, however in S. aegyptiaca and S. cordata decreased hydrogen peroxide content
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Perez-Garcia, F., J. M. Iriondo, M. E. Gonzalez-Benito, L. F. Carnes, J. Tapia, C. Prieto, R. Plaza e C. Perez. "GERMINATION STUDIES IN ENDEMIC PLANT SPECIES OF THE IBERIAN PENINSULA". Israel Journal of Plant Sciences 43, n. 3 (13 maggio 1995): 239–47. http://dx.doi.org/10.1080/07929978.1995.10676608.
Testo completoAbstract (sommario):
The germinative behavior of nine plant species of the Iberian Peninsula, four of them catalogued as vulnerable or endangered by the International Union for the Conservation of Nature, was studied under controlled laboratory conditions. Most of the species studied germinated better at relatively low temperatures (15 °C and 20 °C) and, in general, high germination rates were also obtained at alternating temperatures (25/15 °C). Coronopus navasii germinated over 60% at 25 °C, the highest temperature used in this study. Lavatera oblongifolia did not surpass 20% germination under any of the conditions assayed. Seed coat scarification increased germination in Helianthemum squamatum, while seed pretreatments with hot water or sulfuric acid were effective in H. polygonoides. Less favorable results were obtained in Lavatera oblongifolia, whereas scarification was completely ineffective in Onobrychis peduncularis ssp. matritensis.
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Mahal, Mst Ferdowsi. "Effects of fungicides and plant extracts on seed germination and seed associated mycoflora of Lens arietinum L. and Lathyrus sativus". Journal of Bio-Science 22 (21 ottobre 2016): 101–10. http://dx.doi.org/10.3329/jbs.v22i0.30014.
Testo completoAbstract (sommario):
Contexts: seed treatment reduced seed mycoflora. Evidences revealed that chemical fungicides and plant extracts were effectively controlled seed mycoflora and enhanced seed germination of pulse crops.Objectives: To determine the effects of chemical fungicides and plant extracts on seed germination and seed associated mycoflora on Lens arietinum L. (lentil) and Lathyrus sativus (khesari).Materials and Methods: All the samples were collected Rajshahi region during June - August 2012. The detection of seed mycoflora, seed germination and seed treatment with fungicides and plant extracts were carried out by using the blotter test (ISTA-1966).Results: Seed germination percentage was significantly (p?0.05) increased with both the treatments. Captan (1.2%) was more effective in comparison with Dithane M-45 (1.4%) and seed germination (%) was gradually increased with increase of the doses of fungicides. Seed associated mycoflora also significantly (p?0.05) varied with the treatments. Aspergillus flavus was the most dominant fungi in lentil and Fusarium oxysporum was in khesari for both the treatments and control. No fungi were recorded at 1.2 and1.4% doses of Captan and Dithane M-45 treated seeds of both pulses. Plant extracts increased germination percentage over control and showed different levels of antifungal activity against seed associated mycoflora (SAM) of both pulse seeds. Among the extracts, Allium sativum showed promising result in controlling of SAM of lentil and khesari. Besides this, A. flavus was remarkably eliminated with the all types of used extracts.Conclusion: From this study it had been clearly found that seed treatment with chemical fungicides and plant extracts were controlled seed mycoflora of lentil and khesari and increased seed germination.J. bio-sci. 22: 101-110, 2014
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Da Silva, Paulo Vinicius, Paulo Henrique Vieira dos Santos, Patricia Andrea Monquero, Elias Silva de Medeiros, Bruna Ferrari Schedenffeldt, Roque De Carvalho Dias, Estela Maris Inácio et al. "Weed control in different germination fluxes with preemergent herbicides on sugarcane straw under dry periods". Revista de la Facultad de Ciencias Agrarias UNCuyo 56, n. 1 (27 giugno 2024): 74–82. http://dx.doi.org/10.48162/rev.39.124.
Testo completoAbstract (sommario):
Preemergent herbicides are a frequent weed control strategy. Considering different crop germinative fluxes, these products must present long-lasting weed control. This study evaluated preemergent herbicides in different germination fluxes of Merremia aegyptia, Mucuna aterrima and Ricinus communis when applied to different quantities of straw and different simulated dry periods. The experiment was conducted in a 4 × 2 × 2 factorial design with four replications. The treatments included four dry periods (0, 30, 60, and 90 days), two straw quantities (0 and 10 t ha 1), and two germination fluxes. The herbicides amicarbazone (1225 g ha-1), imazapic (147 g ha- 1), sulfentrazone (800 g ha-1), and tebuthiuron (900 g ha-1) were applied for preemergence weed control, and germination flush fluxes were evaluated at 7, 14, 21, 28, and 35 days after emergence (DAE) while verifying plant dry mass. Amicarbazone controlled less than 80% of the studied species at the 90-day dry period in the presence of straw. Imazapic did not present control residue for any of the species analyzed. Sulfentrazone showed the same control pattern at all germination fluxes, regardless of the amount of straw. Tebuthiuron successfully controlled all species in the first germination flush, exceeding 80% regardless of the amount of straw. Herbicides associated with straw quantities and dry periods have a significant impact on M. aegyptiaca, M. aterrima and R. communis. Highlights: The herbicide amicarbazone demonstrated efficacy in controlling during the first germination period of the three weed species. The presence of sugarcane straw significantly influenced the herbicides' control efficacy, especially during prolonged dry periods. The combination of straw and extended dry periods resulted in a reduction in control rates with tebuthiuron.
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Qiu, Jie, Yuguang Bai, Yong-Bi Fu e John F. Wilmshurst. "Patterns of amplified restriction fragment polymorphism in the germination of Festuca hallii seeds". Seed Science Research 20, n. 3 (7 giugno 2010): 153–61. http://dx.doi.org/10.1017/s0960258510000188.
Testo completoAbstract (sommario):
AbstractTiming of seed germination influences plant lifetime fitness and can affect the ability of plant populations to colonize and persist in changing environments. However, the genetic variation of the seed germination response remains poorly understood. The amplified restriction fragment polymorphism (AFLP) technique was applied to characterize the genetic variation of germinated seeds collected from three Festuca hallii populations in the Canadian prairie. Three subpopulations with early, intermediate and late germination were identified from each population, based on germination tests at 10, 15 and 20°C in controlled growth chambers. Three AFLP primer pairs were employed to screen a total of 540 assayed seedling samples and 188 polymorphic AFLP bands were scored for each sample. None of the assayed AFLP bands were significantly associated with seed germination, but marked differences in estimates of mean band frequency were observed for various groups of germinating seeds under different test temperatures. Partitioning of the total AFLP variation showed that 5.9% AFLP variation was present among seeds of the three populations, 0.3% among seeds of three germination subpopulations, and 0.5% among seeds grouped for germination temperature. Genetic differentiation was significant among 27 groups of seeds representing population, germination timing and test temperature. Subpopulations with early and intermediate germination shared similar genetic backgrounds and were genetically differentiated from the late germination subpopulation. These results indicate that seed genotypes respond slightly differently to environmental variation, resulting in significant but weak genetic differentiation in the germination of F. hallii seeds. Implications for plant establishment and fescue restoration are discussed.
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Mavi, Kazim, e Ibrahim Demir. "Controlled Deterioration and Accelerated Aging Tests Predict Relative Seedling Emergence Potential of Melon Seed Lots". HortScience 42, n. 6 (ottobre 2007): 1431–35. http://dx.doi.org/10.21273/hortsci.42.6.1431.
Testo completoAbstract (sommario):
The emergence of 22 commercial seed lots (12 in 2005 and 10 in 2006) of melon (Cucumis melo L.) with laboratory germinations greater than 90% were compared in low temperature (LTE), mechanical stress (MSE), high temperature (HTE), and salt stress (SSE) sowing conditions. The seedling emergence percentage ranged between 18% and 79% for LTE, 15% and 90% for MSE, 27% and 84% for HTE, and 49% and 92% for SSE in 2005; and 43% and 85% for LTE, 30% and 82% for MSE, 56% and 91% for HTE, and 49% and 89% for SSE in 2006. The germination of the lots was determined after controlled deterioration (CD) with 20% or 24% moisture content (MC) and accelerated aging (AA) at 40 and 45 °C in 2005; or at 45 and 47 °C in 2006 for 48, 72, 96, 120, and 144 h. Germination after various combinations of CD and AA was positively and significantly (P < 0.05) correlated with LTE, MSE, HTE, and SSE. Correlation values (0.17 to 0.78) of the initial laboratory germination were much lower than those of both aging tests. The optimum CD conditions of 48 h and 20% MC at 45 °C and AA conditions of 120 h at 45 to 47 °C are suggested as vigor tests to estimate relative seedling emergence of melon seeds.
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Zargar, Tahoora Batool, Faiza Ashraf e Szilvia Veres. "Peg- Induced Drought Stress Effects on Spinach Germination Parameters". Review on Agriculture and Rural Development 10, n. 1-2 (14 dicembre 2021): 126–32. http://dx.doi.org/10.14232/rard.2021.1-2.126-132.
Testo completoAbstract (sommario):
Exposure to the drought stress reduces germination rate and seedling's growth with significant variations from crop to crop. An unavoidable consequence of drought exposure is the generation of reactive oxygen species. They can be extremely reactive with several cellular constituents such as proteins, lipids, and nucleic acids. Spinach (Spinacia oleracea L.) is one of the most consumed vegetable species, rich in vitamins, such as vitamin C, and minerals, which are essential for human health. Besides, spinach contains large amounts of bioactive molecules such as glucuronic acid derivatives of flavonoids and p-coumaric acid derivatives that exhibit strong antioxidant activity Osmotic solutions of polyethylene glycol (PEG) are commonly used to control water potential in seed germination studies. PEG reduces the water potential of osmotic solutions but may limit oxygen availability to germinating seeds. The purpose of this study was to determine whether seed immersion in PEG solution had a detrimental effect on total Germination percentage, Relativized percentage, Mean germination time, Mean germination rate, Coefficient of variation of germination time, Coefficient of the velocity of germination, Germination index, Uncertainty of germination process, Synchronization index, Time to 10% germination, Time to 25% germination, Time to 50% germination, Time to 75% germination, Time to 90% germination, Time from 10 to 90% germination, Time from 25 to 75% germination, Mean daily germination Percent, Peak value for germination, Germination value. A controlled experiment was conducted to investigate the effects of drought stress, induced by PEG, on these germination parameters in Spinach. For control, seeds were treated with nutrient solution, and 2.5% PEG was used to induce drought stress. The seeds were germinated geotropically between moisten filter papers. Each roll contained 30 seeds. Overall germination parameters showed a decrease as compared to control. The germination percentage of control seeds of Spinach oleracea L. was 79% while those treated with PEG were only 63%. Similarly, the relativized percentage decrease was observed in the case of PEG-treated seeds. Relativized percentage of control seeds was 91% as treated seeds were only 73%. Both showed a significant decrease as compared to the control.
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Li, Thomas S. C., K. E. Bedford e P. L. Sholberg. "Improved Germination of American Ginseng Seeds Under Controlled Environments". HortTechnology 10, n. 1 (gennaio 2000): 131–35. http://dx.doi.org/10.21273/horttech.10.1.131.
Testo completoAbstract (sommario):
Traditionally, American ginseng (Panax quinquefolium L.) seeds are stratified for 18 to 22 months, before seeding, in a sandbox buried outdoors in late August or early September. Uncontrolled fluctuating temperature and moisture levels and the presence of pathogenic organisms in the seed box can cause seeds to sprout prematurely, rot, dry out and die. A study was initiated to shorten the lengthy stratification period, and to increase seed viability and percentage of germination by stratifying seeds indoors under a controlled environment. Seeds were subjected to various periods of warm [15 or 20 °C (59 or 68 °F)] and cold [2 °C (35.6 °F)] temperature stratification regimes in growth chambers. Embryo growth and viability, and seed moisture content were tested periodically during stratification. The best warm regime for embryo development, seed viability and germination after subsequent cold treatment was 15 °C (59 °F). The first “split” seeds, indicating incipient germination, were observed after 3 months of warm [15 °C (59 °F)] and 4 months of cold [2 °C (35.6 °F)] treatment, when average embryo length reached 6 mm (0.24 inch). Greenhouse germination of stratified seeds was as high as 80%. The results from this study indicate that good germination is possible when ginseng seeds are stratified indoors under a controlled environment and seeds can be made to germinate at any time of the year.
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Kleemann, Samuel G. L., Bhagirath S. Chauhan e Gurjeet S. Gill. "Factors Affecting Seed Germination of Perennial Wall Rocket (Diplotaxis tenuifolia) in Southern Australia". Weed Science 55, n. 5 (ottobre 2007): 481–85. http://dx.doi.org/10.1614/ws-06-197.1.
Testo completoAbstract (sommario):
Germination response of perennial wall rocket to temperature, light, osmotic potential, and depth of burial emergence was evaluated under controlled environmental conditions. The effect of seed burial depth on seedling recruitment in the field was also investigated at Roseworthy, South Australia. Under optimal conditions (30 C, light/dark) germination of perennial wall rocket was rapid, with 90% of seeds germinating within 48 h of imbibition. Germination was reduced (20%) at lower, suboptimal temperatures (10 to 20 C) when seeds of perennial wall rocket were exposed to light. Germination declined with increasing osmotic potential and was completely inhibited at osmotic potentials of −1.5 MPa. Perennial wall rocket emergence was greatest from seeds placed on the soil surface, but some seedlings (< 10%) emerged from a depth of 0.5 to 2 cm. Under both field and growth-cabinet conditions, the greatest seedling emergence of perennial wall rocket occurred from seed present on the soil surface; however, the level of absolute recruitment from the seed bank was much lower (< 5%). Information gained from this study will further improve our understanding of the germination behavior of perennial wall rocket and contribute to developing sustainable strategies for its control.
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Lee, Chin Won, John C. Thomas e Stephen L. Buchmann. "Factors Affecting in Vitro Germination and Storage of Jojoba Pollen". Journal of the American Society for Horticultural Science 110, n. 5 (settembre 1985): 671–76. http://dx.doi.org/10.21273/jashs.110.5.671.
Testo completoAbstract (sommario):
Abstract Conditions for in vitro germination of jojoba [Simmondsia chinensis (Link) Schneider] pollen were optimized in order to study the influence of storage temperature on viability. A medium consisting of 300 mg·liter−1 CaCl2·2H2O, 100 mg·liter−1 KNO3, 10 mg·liter−1 H3BO3, 20% sucrose, and 4% to 5% Difco Bacto-agar was optimal for germinating both fresh and stored pollen. Pollen germinated readily in media with a pH range of 4 to 8. The optimum incubation temperature range for pollen germination was 25° to 30°C. When stored at room temperature (22° to 25°), the initial pollen viability was decreased to 50% in 3 weeks and to 0% after 10 weeks, as determined by in vitro germination. Pollen stored at 4° maintained its initial viability for 10 weeks, followed by a gradual decrease in germination to 70% in 17 weeks and 0% after 22 weeks. Pollen stored at −196° in liquid nitrogen for 2 years retained a germination percentage as high as that of fresh pollen. The eryogenieally stored pollen, when used in controlled pollinations, produced normal fruit set comparable to that with fresh pollen.
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Gogoi, G., P. K. Borua e D. Chetia. "GA3 Assisted Seed Dormancy Breaking in Abelmoschus moschatus Medik. subsp. moschatus". Cercetari Agronomice in Moldova 49, n. 4 (1 dicembre 2016): 27–34. http://dx.doi.org/10.1515/cerce-2016-0033.
Testo completoAbstract (sommario):
Abstract Abelmoschus moschatus Medik. subsp. moschatus is a wild uncultivated variety of common lady’s finger (Abelmoschus esculentus) possessing a high degree of seed dormancy. Methods of dormancy breaking in the seed of the plant were investigated through different physical and chemical methods. Different preconditioning treatments including hot water, dry heat, physical scarification and chemical treatments including exogenous GA3 were applied to explore the initiation in germination. Seeds were germinated under the controlled photoperiod and temperature. The viability of the test seeds was estimated by topographical 2, 3, 5-Triphenyltetrazolium chloride (TTC) solution test. Highest germination percentage was obtained in the seeds treated with the exothermic reaction of H2SO4 and H2O, followed by exposure to gibberellic acid (GA3). The exposure time of exogenously applied GA3 had a significant influence on the germination response. The optimum germination temperature was found to be 30 ± 0.5°C. Treatment with 0.75% of 2, 3, 5-Triphenyltetrazolium chloride solution for 4 h at 35 ± 0.5°C enabled to correlate the viability of the seeds with the germinative values. Maximum germination was induced through this technique and dormancy of the seed can be attributed due to hard impermeable seed coat and endogenous physiological factor.
22
Teixeira, Márcia Torres, Henrique Duarte Vieira, Sílvio Lopes Teixeira e Roberto Ferreira da Silva. "Influence of disinfestation and osmotic conditioning on the germinating behavior of australian royal palm (Archontophoenix alexandrae)seeds". Revista Brasileira de Sementes 29, n. 1 (aprile 2007): 155–59. http://dx.doi.org/10.1590/s0101-31222007000100021.
Testo completoAbstract (sommario):
The technique of Osmotic Conditioning, which consists of partial and controlled hydration of the seeds, has obtained success with various species of seeds, increasing the germinating span and tolerance to the adverse conditions of the environment, and has also reduced the time elapsed between sowing and the emergence of the plants. Associated to ideal storage conditions, the treatment has increased the performance of the seeds of tropical wood species. Aiming at studying the germinating environment and the effect of osmotic conditioning on the germination of seeds of the Australian Royal Palm tree, two experiments were performed. The first one evaluated the effect of disinfestation of the seeds of the Australian Royal Palm tree with NaClO. The treatments applied were: 0.5% sodium hypochlorite, exposure periods of 5, 15, 30, 45, 60, 90, 120 and 240 minutes, and the fungicide Captan, as control. The treatments with NaClO did not differ in relation to the final percentage of germination and to the germination speed index, and did not differ from the treatment control. The second test evaluated solutions with the following osmotic potentials: 0.0MPa (pure water), -0.4MPa, -0.6MPa and -0.8MPa, exposed for the periods of 10 and 20 days. The final percentage of germination did not differ among the treatments. The seeds hydrated in pure water for a period of 20 days showed a germination speed index significantly superior to the other treatments, and they did not show significant differences among themselves.
23
Shibata, Marília, Cileide Maria Medeiros Coelho, Luciana Magda de Oliveira e Cristhyane Garcia. "Accelerated aging of ipê seeds under controlled conditions of storage". Revista Brasileira de Sementes 34, n. 2 (giugno 2012): 247–54. http://dx.doi.org/10.1590/s0101-31222012000200009.
Testo completoAbstract (sommario):
This research was aimed at studying effects of storage and accelerated aging on germination and profile of storage proteins in Handroanthus albus seeds. These were stored into a cold chamber (± 8 ºC; RH ± 40%) and after periods of 0, 3, 6, 9, and 12 months of storage, were subjected to accelerated aging for 0, 24, 48, 72, and 96 hours. Relationships between germination and proteins profile were assessed. Germination test was performed at 25 ºC, under constant light. For protein extraction, 125 mg of seeds were macerated in 2 mL of extraction buffer (1M Tris-HCl; pH 8.8) and applied to SDS-PAGE polyacrylamide gel at 80 V .15 h-1. Twelve month storage, combined with 72 hours accelerated aging have increased germination in approximately 65% when compared to non-aged seeds or to seeds with 24 h of accelerated aging. Besides beneficial effects, degradation and synthesis of different proteins were observed. It was concluded that germination of Handroanthus albus seeds, when not subjected to accelerated aging, is favored by storage in cold chamber during three to six months, or from nine to 12 months when subjected to accelerated aging process. Storage proteins may be associated to those increases, and hence further studies are needed.
24
Thanos, C. A., e K. Mitrakos. "Watermelon seed germination. 2. Osmomanipulation of photosensitivity". Seed Science Research 2, n. 3 (settembre 1992): 163–68. http://dx.doi.org/10.1017/s096025850000129x.
Testo completoAbstract (sommario):
AbstractSeed germination of watermelon (Citrullus lanatus cv. Sugar Baby) was fully suppressed by intermittent far-red (FR) irradiation (1 min every 30 min). When the intervening dark period was increased, a linearly increasing final germination percentage was obtained. However, a 4-day intermittent FR treatment induced phytochrome-controlled dormancy and the longer the dark interval the deeper was the dormancy of the non-germinated seeds. When seeds were soaked in a fully inhibitory osmotic solution, no dormancy was imposed. However, a single FR pulse at the time of transfer induced partial, secondary dormancy; the kinetics of the imposition of dormancy followed a negative exponential curve (half-life 1.5 days; 3 days for the cultivar Crimson Sweet). Seeds osmotreated for 10 days in darkness and subsequently dehydrated (with and without a final FR pulse) acquired germination characteristics similar to those in light-requiring and dark-germinating achenes, respectively, of the lettuce cultivar Grand Rapids. In the light-requiring osmomanipulated seed population, the induction of germination was brought about by the low-energy reaction of phytochrome, chilling, dry storage and decoating. The transformation through osmomanipulation of the dark-germinating watermelon seeds (the inhibition of which required prolonged exposure to light) to positively or negatively photosensitive seeds (that responded to brief light pulses), might be attributed to the slow relaxation of existing meta-Fa and meta-Rb phytochrome intermediates to Pfr upon hydration.
25
Carter, Christy T., e Irwin A. Ungar. "Germination response of dimorphic seeds of two halophyte species to environmentally controlled and natural conditions". Canadian Journal of Botany 81, n. 9 (1 settembre 2003): 918–26. http://dx.doi.org/10.1139/b03-086.
Testo completoAbstract (sommario):
To determine whether or not tolerance limits at the germination stage of development and annual germination patterns affect plant distribution in an inland salt marsh, we assessed germination of dimorphic seeds for Atriplex prostrata Boucher ex DC. and Salicornia europaea L. under field and laboratory conditions. Statistically significant differences were found in germination across marsh zones for both species in the field. However, germination percentages for small seeds of A. prostrata and S. europaea were above 50% and 75%, respectively, across all zones for seeds placed on the surface. For large seeds of each species placed on the surface, germination was above 90% across all zones. Small seeds for both species had primary dormancy, a light requirement for germination, and appeared to exhibit dormancy cycling. Large seeds of A. prostrata were nondormant from December through March, whereas large seeds of S. europaea were nondormant when produced. Persistent seed banks were most likely to be formed from small seeds of both species. Seeds typically germinate in the spring when salinity across the marsh is sufficiently low for seeds to germinate in all zones, indicating that the germination stage of development does not effect the spatial distribution of A. prostrata or S. europaea on the marsh.Key words: Atriplex prostrata, seed dormancy and germination, halophyte, Salicornia europaea, seed dimorphism, salt marsh zonation.
26
Silva, Arthur Batoqui Costa e., Ícaro Monteiro Galvão, Rafael Marani Barbosa, Clíssia Barboza da Silva e Roberval Daiton Vieira. "Controlled deterioration test for evaluation of sunn hemp seed vigor". Journal of Seed Science 37, n. 4 (dicembre 2015): 249–53. http://dx.doi.org/10.1590/2317-1545v37n4151816.
Testo completoAbstract (sommario):
The controlled deterioration test is efficient for seed vigor evaluation of several species. However, the procedures conditions are incipient, especially in respect to tropical forages such as sunn hemp, which still does not have a standardized procedure. The objective of this research was to adjust the procedures for a controlled deterioration test in Crotalaria juncea L. seeds. For this, five commercial seed lots were evaluated for water content and initial physiological potential (germination test, first germination count, germination speed index, saturated salt accelerated aging with NaCl, electrical conductivity and seedling field emergence). For controlled deterioration test, the initial seed moisture content was adjusted to 18, 21 and 24% and, subsequently, the samples were exposed at 45 °C during 24 hours. Seed germination test was conducted with the use of sand as substrate. Evaluations were performed on the fourth, fifth and sixth day after sowing. The controlled deterioration test for sunn hemp seeds should be performed with 24% seed moisture content, at 45 °C during 24 hours, and the test evaluation on the fourth day after sowing.
27
Nguyen, Chi D., Jianjun Chen, David Clark, Hector Perez e Heqiang (Alfred) Huo. "Effects of Maternal Environment on Seed Germination and Seedling Vigor of Petunia × hybrida under Different Abiotic Stresses". Plants 10, n. 3 (19 marzo 2021): 581. http://dx.doi.org/10.3390/plants10030581.
Testo completoAbstract (sommario):
Seed germination and seedling vigor can be affected by environmental cues experienced by the mother plant. However, information about how the maternal environment affects seed quality is scarce in ornamental plants. This study aimed to investigate the effects of two different maternal environments on the seed germination and seedling vigor of Petunia × hybrida under a variety of abiotic stresses. Petunia mother plants were grown in either a greenhouse during the summer months or an indoor controlled-temperature-and-light environment. Collected seeds were subjected to external stressors, including polyethylene glycol (PEG), sodium chloride (NaCl), high temperature, and abscisic acid (ABA), to determine seed germination percentage and seedling vigor. Results indicated that seeds harvested from the mother plants grown in a controlled environment germinated better than seeds harvested from the mother plants grown in the greenhouse when suboptimal germination conditions were applied. Additionally, the seedlings from the controlled maternal environment performed better in both ABA and salinity stress tests than the greenhouse seedlings. Interestingly, the greenhouse seedlings displayed less reactive oxygen species (ROS) damage and lower electrolyte leakage than the controlled environment seedlings under dehydration stress. The difference in germination and seedling vigor of seeds from the two different maternal environments might be due to the epigenetic memory inherited from the mother plants. This study highlighted the strong impact of the maternal environment on seed germination and seedling vigor in Petunia and may assist in high-quality seed production in ornamental plants.
28
Onyango, Alice Adongo, Shadrack Kinyua Inoti, Nelson Maara e James Munga Kimondo. "Effect of Seed Extraction Period and Germination Temperature on Viability of Pinus patula Under Controlled Conditions". Asian Journal of Research in Agriculture and Forestry 10, n. 1 (15 febbraio 2024): 61–71. http://dx.doi.org/10.9734/ajraf/2024/v10i1269.
Testo completoAbstract (sommario):
A number of coniferous species have demonstrated varied cone responses to the temperature intensities for seed release and subsequent seed germination behaviour. This study investigated the interactions of cone physical characteristics (weight and width), exposure duration (6,12 and 24 hours) at a fixed extraction temperature (65°C) and the germination temperature (22, 27 and 32°C) on seed quality of Pinus patula. The experimental design was a factorial experiment (4×3×3) laid down in a completely randomized design (CRD), with thirty-six treatments replicated 3 times. Analysis of the difference in means from the three factor effects from ANOVA was performed using R Statistical software. Where significant differences were observed, post hoc tests were carried out to separate means using the Tukey test at 5 % significance level. Results showed significant (p=0.001) differences in germination performance as a result of cone characteristics, extraction exposure periods, and germination chamber conditions. Seeds extracted from heavy cones and exposed to germination temperature of 32℃ demonstrated the highest germination percent at 90% while the lowest was 20% from light cones exposed to similar germination temperature conditions. Negative and significant correlation coefficients were observed in germination of seeds from narrow and light cones, thus cone sorting for heavy and wide cones was recommended for better germination performance of P. patula seed germplasm.
29
Kamenetsky, Rina, Joanna Gębura e Krystyna Winiarczyk. "Germination strategy of Allium victorialis, a wild edible plant with high commercial potential". Botany 95, n. 2 (febbraio 2017): 195–202. http://dx.doi.org/10.1139/cjb-2016-0126.
Testo completoAbstract (sommario):
The spring ephemeral Allium victorialis grows naturally in Europe, Asia, and North America. Because of its pleasant taste, aroma, and nutraceutical properties, it is intensively gathered in its natural habitats by the local populations. To introduce A. victorialis as a new crop, technologies of mass-propagation and effective production must be developed. However, the biology of seed dormancy and germination in this species is not clear, and numerous attempts at controlled seed germination have not succeeded. We employed a systematic approach for seed germination of this species under controlled conditions. Two main factors, post-ripening seed age and germination temperature regimes, were studied in combination with various germination techniques. As opposed to common conceptions, our results show that the seeds of A. victorialis do not experience morphological, physical, or physiological dormancy, and are completely ready for germination immediately following ripening. Propagation of A. victorialis from seed can be performed by germination of fresh seeds at moderate (20 °C) temperatures, in a sterile planting medium with good aeration. The germination strategy, revealed in this research, opens new prospects for the development of A. victorialis as a new and useful crop.
30
Torres, Salvador B., Maryjane DA Gomes, Francisca Gleiciane da Silva, Clarisse P. Benedito e Francisco ECB Pereira. "Controlled deterioration to evaluate okra seed vigor". Horticultura Brasileira 31, n. 2 (giugno 2013): 317–21. http://dx.doi.org/10.1590/s0102-05362013000200023.
Testo completoAbstract (sommario):
Germination and vigor tests are essential components of seed quality control programs adopted by seed industries. We studied different procedures to perform the controlled deterioration test to identify differences in vigor among okra seed lots. Four seed lots of Colhe Bem cultivar and five seed lots of Santa Cruz 47 cultivar were submitted to the following tests: germination, seedling emergence, controlled deterioration (seeds with moisture contents of 18, 21 and 24% at 45°C for 24 and 48 hours) and moisture content. The controlled deterioration test is efficient to evaluate the physiological potential of okra seeds, and the combination of 24% water, 45°C during 24 hours is recommended.
31
Taylorson, R. B. "Inhibition of germination in Amaranthus albus seeds by prolonged irradiation: a physiological basis". Seed Science Research 1, n. 1 (marzo 1991): 51–56. http://dx.doi.org/10.1017/s0960258500000635.
Testo completoAbstract (sommario):
AbstractAmaranthus albus L. seeds able to germinate in darkness can be prevented from germinating by prolonged irradiation with incandescent light (CIL). The germination in darkness is controlled by pre-existent Pfr. Allowing the seeds to remain in darkness for about 16 h allows an escape from the inhibition by CIL, about comparable with the time required to escape from pre-existent Pfr control. By examining escape from low fluence far-red (FR), it was found that no escape occurred in CIL. It was concluded that the mode of action of CIL in inhibiting A. albus seed germination involved prevention of the action of the pre-existent Pfr and a subsequent dormancy which does not allow a response to the Pfr generated by the incandescent light. Other actions of CIL were found but were considered less likely as causative for the inhibition of germination. One was a direct inhibition of radicle elongation and another involved prevention of an increased responsiveness to Pfr induced by treatment at 40°C.
32
Fujikura, Yuzo, e Cees M. Karssen. "Effects of controlled deterioration and osmopriming on protein synthesis of cauliflower seeds during early germination". Seed Science Research 2, n. 1 (marzo 1992): 23–31. http://dx.doi.org/10.1017/s0960258500001070.
Testo completoAbstract (sommario):
AbstractProfiles of proteins synthesized in vivo in radicle tips were compared among unaged, artificially aged (controlled deterioration: 10% moisture content at 42°C for 3 weeks), osmoprimed (−1.5 MPa polyethylene glycol 6000 at 20°C for 1 week), and artificially aged and subsequently osmoprimed cauliflower (Brassica oleracea L.) seeds. Germination and initiation of incorporation of 35S-methionine into radicle tips were delayed by controlled deterioration. Osmopriming accelerated these processes and also alleviated the delays. The labelled proteins were analysed by two-dimensional gel electrophoresis and fluorography. Proteins were found whose expression correlated with the rate of germination, and was reduced by controlled deterioration but enhanced by osmopriming. Subsequent osmopriming reversed the effect of controlled deterioration and even caused an enhancement up to the level of unaged osmoprimed seeds. These proteins appeared to be related to processes preceding visible germination. In unaged seeds, formation of the proteins in the radicle tip began upon imbibition but decreased towards visible germination. On silver-stained gels, one of the proteins was shown to be mobilized by the time of radicle protrusion, while all were found in dry seeds. Proteins whose pronounced expression was observed only after both treatments were also found.
33
Umair, Adnan, Muhammad Abid, Ijaz Ali, Kashif Bashir, Waqas Naseem e Hafiz Abdul Rauf. "Nutrient Priming in Different Maize Cultivars and Evaluation of Vigour Improvement Under Controlled Conditions". Biological Sciences - PJSIR 60, n. 2 (24 agosto 2017): 65–69. http://dx.doi.org/10.52763/pjsir.biol.sci.60.2.2017.65.69.
Testo completoAbstract (sommario):
Laboratory and pot experiments were conducted to study the effect of seed priming on vigourand germination characteristics of different maize cultivars during the year 2011. The seeds of four maizecultivars viz. EV 7004Q, Islamabad Gold, Rakaposhi and Sohan-3 were primed using 0% P (dry seededcontrol), 0.6% P and 1.2% P solutions of KH2PO4 for 16 h. The experiment was laid out in CompleteRandomized Design (CRD) having three replicates. All the seed priming treatments significantly improvedthe plant vigour in terms of enhanced germination percentage, reduced mean germination time (MGT),improved root, shoot lengths and dry matter production. Among the four cultivars of maize the IslamabadGold performed best followed by Sohan-3. Highest germination (94.57%) and vigour index (VI) of 431.66was observed in Islamabad Gold where 1.2% P applied compared to dry seeded control. Nutrient seedpriming may be used to improve germination vigour and crop stand establishment under field conditionsleading to good yield targets in maize under rainfed conditions.
34
Dadach, Mohammed, Ali Benajaoud e Zoheir Mehdadi. "Salt and Drought Effect on Germination and Initial Growth of Lavandula stoechas: A Potential Candidate for Rehabilitation of the Mediterranean Disturbed Coastal Lands". Ekológia (Bratislava) 40, n. 4 (1 dicembre 2021): 301–11. http://dx.doi.org/10.2478/eko-2021-0032.
Testo completoAbstract (sommario):
Abstract Information relating to germination and seedling emergence of a plant aids in determining the species spatiotemporal distribution and also facilitates in designing appropriate plant management strategies within an ecosystem. Lavandula stoechas L. (Lamiaceae), a naturally occurring shrub, is particularly used in pharmaceutical and cosmetic industries. This species, indeed, has the potential for rehabilitation of degraded costal lands. However, various aspects of its seed biology have not yet been recognised. Here, we aimed to assess the effects of different soluble salts (NaCl, CaCl2, MgCl2 and Na2SO4) and drought (as simulated by polyethylene glycol, [PEG]6000) on seed germination patterns and early seedling growth responses. Seeds treated with five iso-concentration (0–100 mM) salinities and five PEG6000 (0 to −1 MPa) levels were incubated in a controlled germinator set at 20°C. The preliminary results revealed that seeds of L. stoechas lacked primary/innate dormancy and they germinated abundantly (89.2% germination) and fast (7.4% day−1) in the absence of stress. Regardless of the kind of salt applied, the germination percentage (GP) and germination rate index (GRI) fell significantly with increasing salinity, and germination ceased completely at 100 mM Na2SO4. In fact, the salinity tolerance index (STI) showed that, among all salts tested, Na2SO4 appeared to have more inhibitory action on germination. In addition, L. stoechas was found to be tolerant to moderate salty stress (<50 mM) in early growth phase. The salt solution parameters (i.e. concentration, electrical conductivity [EC] and salt content) were best correlated with seed/seedling metrics. pH was not a good predictor for salt effects at the germination/seedling stages. Overall, this species seems to be sensitive to drought at the germination and initial growth phases. The germination recovery potential of L. stoechas in both stresses stipulates that this species can be regarded as a promising candidate in the rehabilitation of Mediterranean disturbed coastal habitats.
35
Stevens, J. C., E. G. Barrett-Lennard e K. W. Dixon. "Enhancing the germination of three fodder shrubs (Atriplex amnicola, A. nummularia, A. undulata; Chenopodiaceae): implications for the optimisation of field establishment". Australian Journal of Agricultural Research 57, n. 12 (2006): 1279. http://dx.doi.org/10.1071/ar06031.
Testo completoAbstract (sommario):
Saltbush (Atriplex) species are widely grown in Australia as saltland pastures. Direct seeding practices for saltbush currently result in asynchronous and unreliable seedling establishment (5% successful establishment is not uncommon from field-sown seed). In part this may stem from a limited understanding of Atriplex seed germination requirements. This paper presents findings with 3 Atriplex species, A. amnicola (Paul G. Wilson.), A. nummularia (Lindl.), and A. undulata (D. Dietr), each of which differs in germination characteristics. For A. amnicola, the presence of light (and artificial substitution of light by 1000 ppm gibberellic acid) improved germination under controlled conditions and resulted in a 4-fold increase (70% total emergence) in field emergence of seedlings. For A. undulata, removing bracteoles increased germination under controlled conditions (~15%), with a 1.5-fold improvement in field seedling emergence (55% final emergence); however, seed priming or gibberellic acid application had no significant effect. In contrast, for A. nummularia, bracteole removal and light had minor positive effects on germination under controlled conditions, but this did not translate into improved emergence in soil or in the field. Under –0.5 MPa NaCl stress, application of gibberellic acid, salicylic acid, or kinetin to the germination medium significantly increased the final germination percentage of A. amnicola seeds (58, 16, and 14%, respectively) and improved the rate at which seeds germinated. All plant signalling compounds significantly increased final germination percentage and germination rate of A. undulata, albeit with a <10% increase at –0.5 MPa NaCl. Priming seeds with plant signalling compounds had similar effects on seed germination under low water potentials compared to direct treatment of the germination media. The effects of seed priming on Atriplex seedling emergence from saline soils varied among species. Priming with water significantly increased emergence percentage of A. amnicola but had no effect on A. nummularia and A. undulata. Gibberellic acid improved A. amnicola germination parameters only, whereas salicylic acid and kinetin improved the rate of emergence in all 3 species at various levels of salinity. This study suggests that a basic understanding of seed dormancy and germination requirements has the potential to substantially improve field emergence of saltbush species.
36
Marinho, Jéssica de Lucena, José Henrique Bizzarri Bazzo, Claudemir Zucareli e Inês Cristina de Batista Fonseca. "Controlled deterioration test to evaluate the physiological potential of sweet corn seeds". Semina: Ciências Agrárias 42, n. 3 (19 marzo 2021): 949–62. http://dx.doi.org/10.5433/1679-0359.2021v42n3p949.
Testo completoAbstract (sommario):
The evaluation of the physiological potential of sweet corn seeds is essential in a quality control program and the choice of vigor tests using an adequate analysis methodology is essential to obtain reliable results. In this sense, this study aimed to standardize the methodology of the controlled deterioration test through combinations between time and temperature to evaluate the vigor of sweet corn seeds. Six lots of sweet corn seeds were characterized by the degree of moisture and the initial physiological potential through the following tests: germination, first germination count, cold test, electrical conductivity, accelerated aging, length and dry mass of normal seedlings, seedling emergence in sand, and emergence rate index. Subsequently, these lots had their initial water content adjusted to 20% using the wet substrate method. The seeds from the six lots were subjected to the controlled deterioration test under two temperatures for four periods, obtaining a completely randomized design in an 8 × 6 factorial scheme with eight combinations of time/temperature and six lots. Germination and the first germination count were evaluated after the deterioration test. The data were subjected to analysis of variance with a comparison of means by the Tukey test at a 5% significance. The results of the first count and germination tests after deterioration were subjected to a simple linear correlation study together with the initial characterization data. The combinations 8 h – 40 °C and 8 h – 45 °C in the controlled deterioration test were efficient in distinguishing the vigor of seed lots. The shorter exposure period and the first germination count after deterioration are more suitable for evaluating the vigor of sweet corn seeds.
37
Saric-Krsmanovic, Marija, Gajic Umiljendic, Ljiljana Santric e Ljiljana Radivojevic. "Impact of storage conditions on seed germination and seedling growth of wild oat (Avena fatua L.) at different temperatures". Pesticidi i fitomedicina 30, n. 4 (2015): 243–48. http://dx.doi.org/10.2298/pif1504243s.
Testo completoAbstract (sommario):
The influence of seed storage conditions and different temperatures (5?C, 10?C, 15?C, 20?C, 25?C, 30?C and 26?C/21?C) during germination and seedling development on seed germination, shoot length and germination rate of wild oat (Avena fatua L.) was examined. Germinated seeds were counted daily over a period of ten days and shoot length was measured on the last day, while germination rates were calculated from those measurements. The results showed that seed storage under controlled conditions (T1: temperature 24?1?C, humidity 40-50%; T2: temperature 26?1?C, humidity 70-80% and T3: temperature 4?C) for periods of 3 (t1) and 12 (t2) months had a significant influence on germination of wild oat seeds. The percentage of germinated seeds under all examined temperatures was higher when they were stored for 12 months under controlled temperature and humidity. The results also showed that temperature had a significant effect on the percentage of germination and germination rate of A. fatua seeds. The highest total germination occurred at 15?C temperature (T1: t1 - 41.25%, t2 - 44.37%; T2: t1 - 28.13%, t2 - 34.37%; T3: t1 - 10.63%, t2 - 12.50%). Germination percentage under an alternating day /night photoperiod at 26?C/21?C temperature was higher in all treatment variants (T1: t1 - 8.13%, t2 - 10.00%; T2: t1 - 11.87%, t2 - 13.13%; T3: t1 - 2.42%, t2 - 2.70%) than germination in the dark at 25?C, 30?C and 5?C.
38
Nleya, T., R. A. Ball e A. Vandenberg. "Germination of common bean under constant and alternating cool temperatures". Canadian Journal of Plant Science 85, n. 3 (1 luglio 2005): 577–85. http://dx.doi.org/10.4141/p04-151.
Testo completoAbstract (sommario):
In western Canada, common bean is often sown in cool soils, which causes poor germination and uneven stand establishment. A major goal in bean breeding is to find and assess cold-tolerant parental material. Seed germination and emergence of 12 diverse common bean genotypes, which included adapted Prairie cultivars, were evaluated in petri dishes under 15 alternating and five constant temperature regimes. Cumulative heat hours to maximum germination were calculated for all 12 genotypes using a base temperature of 9°C. Six genotypes were tested for emergence in soil in growth chambers at two temperature and three soil moisture regimes. In petri tests, optimal temperatures for bean germination were 16/16°C (day/night temperature) or higher. G8823, G9345 and AC Polaris germinated below 10°C, and all genotypes germinated at 12°C or higher. Rapid germinating genotypes with >0.09 cumulative heat hours per percentage germination were G8823, G9345 and AC Polaris, which took the least number of cumulative heat hours to germinate (<1100 heat hours). CDC Pinnacle was the highest representative of the medium germination rate group, having 1170 heat hours to germination. Emergence and plant development in soil were decreased by low moisture availability or cooler temperatures. Genotypes with >80% emergence in soil were CDC Crocus, CDC Nighthawk, CDC Pinnacle and CDC Polar Bear. Differing genotype rankings in soil versus petri dishes demonstrated that germination in controlled cool conditions may still be complicated by dormancy, moisture availability, seed coat thickness, imbibition rate and differing viabilities of seed lots. G8823, G9345 and AC Polaris are promising genotypes for developing cultivars that can germinate under cool temperatures (<10°C) at the highest rate. Key words: Phaseolus vulgaris, common bean, germination, temperature
39
Silva, Alessandra Vieira da, Jamerson Fabio Silva Filho, Dalcimar Regina Batista Wangen, Lara Bernardes da Silva Ferreira, Brunna Rithielly Rezende e Marcos Fernandes-Sobrinho. "The Influence of Lunar Phase on the Germination of Creole Corn in a Controlled Environment". Journal of Agricultural Science 13, n. 3 (15 febbraio 2021): 61. http://dx.doi.org/10.5539/jas.v13n3p61.
Testo completoAbstract (sommario):
Although the influence of lunar phase on plant growth and development has been disregarded by most researchers, there is still little data in the literature regarding the influence of lunar phase within a controlled environment. Objective evaluates the influence of lunar phase on the germination of creole corn and on seedling development in a controlled environment. The experimental design was completely randomized with the following treatments: four lunar phases (full, waxing, waning and new), with four replications totaling 50 seeds per treatment. The treatments started on the first day of the waxing phase and extended to the full phase within the same month, respecting the germination period (nine days) and the length of each moon phase (roughly seven days). The following parameters were evaluated: germination rate, seedling length, fresh and dry weight of shoots and roots. Seedlings germinated during the waning lunar phase were longer and had greater fresh root weight and greater fresh and dry shoot weights than did seedlings germinated during the other phases. However, some limiting factors (long term experiments and in different places in the world) must be considered in future research to determine whether moon phase affects germination. Thus, longer-term, controlled, and modeled studies are needed to analyze external factors, which may influence the germination of cultivar seeds.
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ALAM, M. Z., T. STUCHBURY e ROBERT E. L. NAYLOR. "EARLY IDENTIFICATION OF SALT TOLERANT GENOTYPES OF RICE (ORYZA SATIVA L.) USING CONTROLLED DETERIORATION". Experimental Agriculture 42, n. 1 (gennaio 2006): 65–77. http://dx.doi.org/10.1017/s0014479705003030.
Testo completoAbstract (sommario):
The response of germination and early seedling growth to levels of salinity (0, 50, 100, 150, 200 and 250 mM NaCl) were examined in single seed lots of ten modern rice genotypes. Unaged and deteriorated rice seeds were germinated in rolled paper towels and in Petri dishes. Initial seed quality, final germination, germination rate and early seedling growth were assessed. The samples of the rice genotypes differed in their initial seed quality (measured in terms of Ki). The effect of deterioration varied depending upon the initial seed quality and the severity of the treatment imposed. Ageing (using the technique of controlled deterioration, CD) for up to 24 h had no effect on final germination levels. Although CD for 30 h only reduced final germination slightly, ageing for 36 or 48 h reduced it greatly. Controlled deterioration for 36 h or longer reduced the final length and the rate of extension of both the plumule and radicle. Combining information about germination in salt solution with that about seed quality enabled a distinction to be made between varieties which performed poorly because they were genetically salt-susceptible from those which germinated poorly due to poor seed quality. It is argued that the seed vigour of seed lots used in genotype evaluation should be assessed in order to avoid discarding potentially useful genotypes because of poor physiological seed quality.
41
Annapurna, D., T. Rathore e Geeta Joshi. "Effect of various media on germination and seedling growth of Santalum Album L." Journal of Non-Timber Forest Products 14, n. 1 (1 marzo 2007): 33–36. http://dx.doi.org/10.54207/bsmps2000-2007-h4r63m.
Testo completoAbstract (sommario):
The study was undertaken with different germination media like; sand, soil, vermiculite, perlite, soilrite, cocopeat and compost either alone or in combination under semi controlled conditions with an objective to find their effect on the germination percentage, germination value and seedling growth of Santalum album L. The study revealed that, media containing either pure sand or pure vermiculite or Cocopeat with Vermiculite, Charcoal and neemcake in 10:6:3:1 ratio favoured high germination percentage and germination value as compared to other treatments. As such, effect of germination media on seedling growth was not observed. Any one of these three media can be used for the improved seed germination of S. album based on the availability and convenience.
42
Upadhyaya, Hari D., Yi-Hong Wang, Dintyala V. S. S. R. Sastry, Sangam L. Dwivedi, P. V. Vara Prasad, A. Millie Burrell, Robert R. Klein, Geoffrey P. Morris e Patricia E. Klein. "Association mapping of germinability and seedling vigor in sorghum under controlled low-temperature conditions". Genome 59, n. 2 (febbraio 2016): 137–45. http://dx.doi.org/10.1139/gen-2015-0122.
Testo completoAbstract (sommario):
Sorghum is one of the world’s most important food, feed, and fiber crops as well as a potential feedstock for lignocellulosic bioenergy. Early-season planting extends sorghum’s growing season and increases yield in temperate regions. However, sorghum’s sensitivity to low soil temperatures adversely impacts seed germination. In this study, we evaluated the 242 accessions of the ICRISAT sorghum mini core collection for seed germination and seedling vigor at 12 °C as a measure of cold tolerance. Genome-wide association analysis was performed with approximately 162 177 single nucleotide polymorphism markers. Only one marker locus (Locus 7-2) was significantly associated with low-temperature germination and none with vigor. The linkage of Locus 7-2 to low-temperature germination was supported by four lines of evidence: strong association in three independent experiments, co-localization with previously mapped cold tolerance quantitative trait loci (QTL) in sorghum, a candidate gene that increases cold tolerance and germination rate when its wheat homolog is overexpressed in tobacco, and its syntenic region in rice co-localized with two cold tolerance QTL in rice. This locus may be useful in developing tools for molecular breeding of sorghums with improved low-temperature germinability.
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Simão, Edson, Adriana Tiemi Nakamura e Massanori Takaki. "The germination of seeds of Epiphyllum phyllanthus (L.) Haw. (Cactaceae) is controlled by phytochrome and by nonphytochrome related process". Biota Neotropica 10, n. 1 (marzo 2010): 115–19. http://dx.doi.org/10.1590/s1676-06032010000100011.
Testo completoAbstract (sommario):
The Epiphyllum phyllanthus seeds present high sensitivity to light and their germination can be promoted by dim green safe light through the very low fluence response mediated by phytochrome A. Part of seed population have phytochrome B in active form (Pfr) enough to promote germination in darkness. Seeds of Epiphyllum phyllanthus germinate in a wide temperature range from 10 to 40°C, reaching complete germination in the range of 15 to 30°C. Above 35°C the germination rate increases indicating control by a non phytochrome related process. The analysis of kinetics of seed germination indicated that the phytochrome A control is less dependent on temperature than phytochrome B controlled process.
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Abdeldinova, Danagul. "Disentangling the effects of liquid nitrogen on impermeable seed coated species". Eurasian Science Review An International peer-reviewed multidisciplinary journal 2, n. 5 (17 maggio 2024): 39–53. http://dx.doi.org/10.63034/esr-93.
Testo completoAbstract (sommario):
Nelumbo nucifera, commonly known as the sacred lotus, is a plant of deep cultural, nutritional, and environmental importance, especially in Asian countries. It is widely used for its edible seeds and roots, and it also has ceremonial significance in many cultural traditions. In addition to its use in cuisine and rituals, Nelumbo nucifera plays a crucial role in aquatic ecosystems, oxygenating the water and providing habitat for various species of wildlife. However, the wider use of Nelumbo nucifera in nature management and agriculture is hindered by the physical dormancy of its seeds. This dormant trait prevents seeds from germinating under normal conditions, thereby limiting their natural dispersal and use in controlled cultivation and recovery projects. Liquid nitrogen (LN) treatment is investigated to disturb the dormancy of impermeable Nelumbo nucifera seeds by physically damaging the seed shell and facilitating water and oxygen penetration. Extremely low temperatures during LN treatment can weaken the seed coat, improving water absorption and promoting germination. This research investigates how LN treatment affects seed germination and seedling growth compared to untreated seeds. Various factors, such as seed quality, treatment duration, and germination conditions, are considered when evaluating the effectiveness of LN treatment. Conduct thorough experiments and optimize LN treatment protocols to maximize the benefits of Nelumbo nucifera seed germination.
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Foolad, M. R., L. P. Zhang e P. Subbiah. "Genetics of drought tolerance during seed germination in tomato: inheritance and QTL mapping". Genome 46, n. 4 (1 agosto 2003): 536–45. http://dx.doi.org/10.1139/g03-035.
Testo completoAbstract (sommario):
A BC1 population (N = 1000) of an F1 hybrid between a stress-sensitive Lycopersicon esculentum breeding line (NC84173; maternal and recurrent parent) and a germination stress-tolerant Lycopersicon pimpinellifolium accession (LA722) was evaluated for seed germination rate under drought stress (DS) (14% w/v polyethyleneglycol-8000, water potential approximately 680 kPa), and the most rapidly germinating seeds (first 3% to germinate) were selected. The 30 selected BC1 seedlings were grown to maturity and self pollinated to produce BC1S1 progeny seeds. Twenty of the 30 selected BC1S1 progeny families were evaluated for germination rate under DS and their average performance was compared with that of a "nonselected" BC1S1 population of the same cross. Results indicated that selection for rapid germination under DS significantly improved progeny germination rate under DS (selection gain = 19.6%), suggesting a realized heritability of 0.47 for rate of germination under DS in this population. The 30 selected BC1 plants were subjected to restriction fragment length polymorphism (RFLP) analysis, and marker allele frequencies for 119 RFLP markers which spanned 1153 cM of the 12 tomato chromosomes were determined. A distributional extreme marker analysis, which measures statistical differences in marker allele frequencies between a selected and a nonselected population, detected four quantitative trait loci (QTLs) for rate of germination under DS in this population. Of these, two QTLs, located on chromosomes 1 and 9, were contributed by the L. pimpinellifolium donor parent and had larger effects than the other two QTLs, located on chromosomes 8 and 12, which were contributed by the L. esculentum recurrent parent. A few BC1S1 families were identified with all or most of the identified QTLs and with germination rates comparable with that of LA722. These families should be useful for the development of germination drought-tolerant tomato lines using marker-assisted selection (MAS). The overall results indicate that drought tolerance during seed germination in tomato is genetically controlled and potentially could be improved by directional phenotypic selection or MAS.Key words: abiotic stress, distributional extreme analysis, heritability, selective genotyping, stress tolerance.
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Alvarenga, Renata Oliveira, e Julio Marcos-Filho. "Vigor evaluation of stored cotton seeds, including the Seed Vigor Imaging System (SVIS®)". Journal of Seed Science 36, n. 2 (giugno 2014): 222–30. http://dx.doi.org/10.1590/2317-1545v32n2944.
Testo completoAbstract (sommario):
This study aimed at evaluating efficiency of different tests to assess cotton seed vigor during storage, including the SVIS® software. Thereby, five cotton seed lots (cv. BRS 293) were stored under controlled environmental conditions of low temperature and relative humidity (10 ºC; 30% RH), and under non-controlled laboratory environmental conditions, for eight months. Evaluations of germination, first germination count, cool germination, accelerated aging test traditional and with saturated salt, field seedling emergence and seedling imaging automated analysis - SVIS® were performed before and after every two storage months. It was concluded that the cool germination, accelerated aging (traditional and with saturated salt), field seedling emergence and seedlings length (SVIS®) are adequate parameters for assessing vigor of cotton seeds during storage, and that both accelerated aging and SVIS® (vigor index and seedlings length) present enough sensitivity to identify changes on seed vigor during storage.
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Silva, João H. C. S., Gilvaneide A. de Azerêdo e Vênia C. de Souza. "Conservation of seeds of cactaceae species endemic to the caatinga biome: Pilosocereus pachycladus and Tacinga inamoena". Revista Caatinga 36, n. 1 (marzo 2023): 115–23. http://dx.doi.org/10.1590/1983-21252023v36n113rc.
Testo completoAbstract (sommario):
ABSTRACT Ecosystems with dry soils are particularly sensitive to climate changes and anthropogenic actions, which represents a threat to the survival of many cactus species. Ex situ seed conservation strategies should be adopted to support in situ conservation. This study evaluated the effect of conservation conditions on germination and vigor of seeds of Pilosocereus pachycladus subsp. pernambucoensis and Tacinga inamoena. The seeds were packaged in paper bags and glass containers and stored under controlled (8 ± 1 °C; 56 ± 2% relative humidity) and non-controlled (24 ± 2 °C; 75 ± 5% relative humidity) environmental conditions for 0 (control), 12, 16, and 20 months. The experiment was conducted in a completely randomized design, in a 2 × 2 × 4 factorial arrangement (conservation environment × packaging × storage period) for each species. The variables evaluated were: water content (%), germination (%), germination speed index (GSI), and mean germination time (MGT). The physiological quality of seeds of both species were preserved when seeds were maintained under controlled environment, regardless of the packaging. However, when stored under non-controlled environment, the packaging in paper bags was more efficient for the conservation of seeds of P. pachycladus subsp. pernambucoensis, and the glass container was more efficient for T. inamoena. This information may be needed for ex situ conservation of these species and to support the recovery of degraded areas susceptible to desertification in the Caatinga biome.
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Eddleman, L. E., e J. T. Romo. "Spotted knapweed germination response to stratification, temperature, and water stress". Canadian Journal of Botany 66, n. 4 (1 aprile 1988): 653–57. http://dx.doi.org/10.1139/b88-092.
Testo completoAbstract (sommario):
Spotted knapweed (Centaurea maculosa Lam.) is an introduced noxious weed on grasslands in the northwestern United States and adjoining Canadian provinces. This research examined germination responses of spotted knapweed to stratification, temperature, and water stress under controlled conditions. Immediately after harvest, germination was sharply reduced by sub- and supra-optimal temperatures and water stress; as seeds aged, germination increased at sub- and supra-optimal temperatures. Total germination was enhanced and days to 50% of final germination (D50) was reduced by cool–moist stratification. Under water stress, germination of unstratified seeds was limited at suboptimal temperatures, but seeds pretreated with cool–moist stratification germinated more rapidly and to a higher percentage over a broader range of temperatures and osmotic potentials.
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Chou, Liang Hsing, Chun Ku Lu e Tsu Ming Chou. "Application of Biodegradable Polymers on Hydroseeding". Advanced Materials Research 415-417 (dicembre 2011): 1257–60. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.1257.
Testo completoAbstract (sommario):
Erosion soil loss is an important problem to be solved. Polyacrylamide (PAM), a biodegradable polymer, has been used in irrigating ditch to reduce soil loss for a long time. It can also be used as an aggregate agent to keep the balance of soil water. The performance of PAM as a soil aggregate agent of silty clay loams was conducted by the wet-sieving method in this study. The effects of PAM on the germination and growth of Bermuda and Bahia were observed. The experiments were conducted in a controlled box with constant temperature and humility. An out-door experiment was also conducted to understand the germination rate of seeds and the development of roots of grasses in ambient condition. Experimental results showed that the addition of PAM would delay the germinations of seeds. However it could enhance the growth of the Bermuda and Bahia grasses.
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Orozco-Segovia, A., M. E. Sanchez-Coronado e C. Vazquez-Yanes. "Light Environment and Phytochrome-Controlled Germination in Piper auritum". Functional Ecology 7, n. 5 (ottobre 1993): 585. http://dx.doi.org/10.2307/2390135.
Testo completo