Tesi sul tema "Cotton growing"

The 1991 growing season was characterized by a cool, wet spring and a cool, dry summer. Heat unit accumulation for the season was the lowest in 5 years at most locations. Precipitation was concentrated in two periods: early (Jan. - Mar.) and late (Nov. - Dec.). Summer rainfall was well below normal at most locations.

Abundant rainfall was the most prominent feature of the 1992 growing season. Monthly precipitation totaled above normal during the first five months of the year, and during August and December. Warm temperatures accompanied the wet weather during the spring planting season and helped boost growing season heat unit totals to near record levels in central and western Arizona. Early fall weather was warm and dry which provided excellent conditions for both finishing the crop and preparing the crop for harvest.

This thesis is a historical geography of cotton production in Arizona from the prehistoric Hohokam cotton farms to the large-scale agribusiness operations that dominate modern Arizona agriculture. The purpose is to chart the expansion and distribution of cotton production and identify important cultural, biological, and physical factors that have influenced cotton planting decisions and so contributed to the evolution of Arizona's commercial cotton production region. In a final analysis, the businesses that are backward- and forward-linked to the growers--such as banks, agricultural implement and agricultural chemical dealers, and cotton ginners and cottonseed processors--have more responsibility in the evolution and endurance of Arizona's cotton production region than do the growers.

Until the 1960s, the Gokwe region of northwestern Zimbabwe was perceived as the wild, remote, and culturally backward domain of the "Shangwe" tribe. Since the introduction of small-holder cotton production in the 1960s, and the influx of immigrants from the south, it has been represented as a miracle of agrarian transformation, a frontier of commoditization, and more broadly, as an exemplar of the transition to modernity. In this thesis, I explore how alternative narratives of commoditization inform modes of state intervention, representations of ethnic difference, and forms of agrarian labour in Gokwe. Using my own ethnographic journey through Gokwe as a referent, I examine the different ways in which colonial maps, indigenous myths, and ritual exchanges variously locate relations of power, labour and identity in social space. Labour forms and commodity relations are continually remade as farmers, traders, ethnographers and administrators argue over the signs of modernity and its antitheses.

The study consisted of two experiments conducted over two growing seasons. Urea ammonium nitrate was used as a source of N at rates of 50, 75, 100 and 150% of levels estimated to be ideal for maximum yield of cotton (Gossvpium hirsutum L.). The nitrogen fertilizer was applied through a drip irrigation system. The yield of seed cotton, flowering pattern, boll set, plant N uptake, and dry matter production were studied in relation to four N fertilizer rates and two plant populations in the 1984 study. Yield of seed cotton, plant N uptake and dry matter production were studied in relation to four N rates, three seeding rates, and three cotton cultivars in the 1985 study. Petiole nitrate patterns were studied both seasons. The effect of N applications on seed cotton yield was dependent upon the initial soil N and the yield possibility. In this study the lower rate of N appeared to be sufficient for the yields obtained. Thinning resulted in reduction of the total number of flowers and significantly decreased yield, but percent boll set was not affected. Nitrogen additions significantly increased plant N uptake and dry matter production as well as petiole NO₃-N levels during the growing season. The N need of cotton under drip irrigation was determined throughout the growing season by using petiole analysis. The levels of petiole NO₃-N for N sufficiency and deficiency which are accepted under furrow irrigation cotton were shown to be applicable for drip irrigated cotton. Yield of DPL-775 and DPL-90 cotton cultivars was significantly higher than that for DPL-41 cotton cultivar in 1985.

Based on extensive UK and African archival research and a wide survey of secondary sources, this thesis examines various aspects of African cotton production from prehistoric to modern times. Its main emphasis is on the interaction of British demand and African supply during the twentieth century colonial period. The British Cotton Growing Association (BCGA), Empire Cotton Growing Corporation (ECGC), Malawi and Tanzania are studied in detail to observe the means by which the BCGA and ECGC articulated British needs and nurtured the African cotton industry and the extent to which East and Central African cotton-growing was directed by external wants, supported by outside input and met local desires. Also examined are the dynamics of competition, control and occasional cooperation between European planters, African smallholders, metropolitan government, various levels of local government administration, large-scale merchants, small traders, Departments of Agriculture and the Colonial Office (CO). Background data is provided in technical appendices and over fifty statistical tables, graphs and maps. Starting with a discussion on the origins of cultivated cottons, the first chapter describes the rise of the Lancashire cotton industry and its search for a regular, secure supply of raw cotton. The second chapter narrates the history of the BCGA, inaugurated in 1902 to meet British cotton requirements, and assesses its success, its inherent dichotomy as 'semi-philanthropic, semi-commercial' and its relationships with the CO, overseas governments and trading firms. It also introduces the ECGC, chartered in 1921, the main subject of the third chapter which spotlights the varied areas of ECGC activity and its role in agricultural research. Chapter 4 bridges the metropolitan-colonial divide with an examination of economics, agriculture and cotton in British territories in Africa, with specific sections on Zimbabwe, Zambia, Kenya and Uganda. Chapters 5 and 6 present overviews of cotton-growing in Malawi and Tanzania, touching on regional variations, constraints on expansion, means of encouragement, ecological effect and economic and production results.

The thesis explores the linked history of the dynamic precolonial handicraft textile industry of Northern Nigeria and the failure of British colonial efforts to capture the cotton harvest for export. During the nineteenth century, Northern Nigeria was politically organised into two major Muslim states: Borno and the Sokoto Caliphate (1804-1900). This vast area of savanna, lying between Lake Chad and the upper Niger, became the British Protectorate Northern Nigeria between 1900 and 1914. Following the creation of the Caliphate in 1804, textile production expanded considerably during the century, with its products being sold over most of West Africa by Hausa merchant networks centred on the city of Kano, which was the largest industrial and commercial centre in tropical Africa. After the proclamation of the British Protectorate, the powerful British Cotton Growing Association attempted to make Northern Nigeria a vast new centre of cotton cultivation. However, most of the cotton cultivated in the area was absorbed by the looms of local weavers benefitting primarily local textile production rather than the export market. Conflicts between the colonial government and market forces, together with the efficiency of local weavers, became important factors in shaping the cotton campaign. The thesis examines how local textile production became a dynamic industry in the nineteenth century and remained so in the early colonial period. My analytic approach is then to consider not a general political economy, but the contours of its economic and social structure, showing how power and benefits occurred in production.

A study was undertaken to obtain information on farmersâ knowledge, attitudes and practices regarding pesticide usage and to determine the amount of pesticide in soil and water samples collected at four cotton producing areas of Mali. The results from a survey of 24 farmers identified various concerns regarding personal and environmental safety. Despite their training, sometimes growers did not use pesticides in an appropriate manner. Highly toxic pesticides are used by farmers with insufficient personal protective equipment. Sixty soil samples and eight water samples from four cotton growing areas in Mali were scanned for detectable levels of fifty pesticides in total. Pesticides were detected in 77% of the soil samples and the main pesticides were p,p-DDT and its breakdown products, endosulfan I endosulfan II, endosulfan sulfate and profenofos. Among the pesticides detected, p,p-DDT use in the study area had not been reported during the past ten years. The most common pesticide detected in the soil samples from cotton growing areas studied was endosulfan II constituting 65% of the detections with a maximum amount of 37 ng/g. Residues detected in soil samples were below the quantification limit for the newer cotton production region of Kita and for the intermediate region of San. Eight pesticides were detected in water samples: ã-BHC (lindane), endosulfan I, endosulfan II, endosulfan sulfate, dieldrin, p,p-DDD, p,p-DDE and atrazine. All detected pesticides in water had concentrations below the quantification limit except for atrazine. Even though pesticides were found at low concentrations in ground water samples, the fact that water from these wells is used for human and animal consumption is of concern. Also, soil pesticides may be taken up by plants and passed on to other organisms feeding on those plants. Further residues studies in the cotton growing areas of Mali are in order to monitor pesticides residues in Malian soils, water and living organisms.
Master of Science

Cotton is a high-value commercial crop in Australia. Although cotton is largely self-pollinating, previous researchers have reported that honeybees, Apis mellifera, can assist in cross-pollination and contribute to improved yield. Until recently, use of bees in cotton had, however, been greatly limited by excessive use of pesticides to control arthropod pests. With the widespread use of transgenic (Bt) cotton varieties and the associated reduction in pesticide use, I decided to investigate the role and importance of honeybees in Bt cotton, under Australian conditions. I conducted two major field trials at Narrabri, in the centre of one of Australia’s major cotton-growing areas, in the 2005-6 and 2006-7 seasons. In the first trial, I particularly assessed methods of manipulating honeybee colonies by feeding pollen supplements of pollen/soybean patties, and by restricting pollen influx by the fitting of 30% efficient pollen traps. I aimed to test whether either of these strategies increased honeybee flight activity and, thus, increased foraging on cotton flowers. My results showed that although supplementary feeding increased bee flight activity and brood production, it did not increase pollen collection on cotton. Pollen traps initially reduced flight activity. They also reduced the amount of pollen stored in colonies, slowed down brood rearing activity, and honey production. However, they did not contribute to increased pollen collection in cotton. In the second trial, I spent more time investigating honeybee behaviour in cotton as well as assessing the effect of providing flowering cotton plants with access to honeybees for different time periods (e.g. 25 d, 15 d, 0 d). In this year, I used double the hive stocking rate of (16 colonies / ha) than in the previous year, because in 2005-6 I observed few bees in cotton flowers. I also conducted a preliminary investigation to assess whether there was any gene flow over a 16 m distance from Bt cotton to conventional cotton, in the presence of a relatively high honeybee population. Both of my field experiments showed that honeybees significantly increased cotton yield via increased boll set, mean weight of bolls, number of seeds / boll, and weight of lint / boll. It was obvious that cotton flowers, and particularly cotton pollen, were not attractive to honeybees, and this was also reflected in the low proportion (5.3% w/w) of pollen from cotton collected in the pollen traps. However, flower visitation rate was generally above the 0.5% level regarded as optimal for cross-pollination in cotton, and this was reflected in increased yield parameters. I recorded a gene flow of 1.7 % from Bollgard®II cotton to conventional cotton, over a distance of 16 m. This is much higher than had previously been reported for Australia, and may have been a result of high honeybee numbers in the vicinity, associated with my managed hives. In an attempt to attract more honeybees to cotton flowers, I conducted an investigation where I applied synthetic Queen Mandibular Pheromone (QMP) (Fruit Boost®) at two rates, 50 QEQ and 500 QEQ / ha, and for two applications, 2 d apart. Neither rate of QMP increased the level of bee visitation to flowers, either on the day of application or the subsequent day. There was also no increase in boll set or yield in plants treated with QMP. My observations of honeybee behaviour in cotton brought some interesting findings. First, honeybees totally ignored extra floral nectaries. Second, most flower-visiting honeybees collected nectar, but the overwhelming majority of them (84%) collected floral nectar from outside flowers: this meant these bees did not contribute to pollination. Those nectar gatherers which entered flowers did contribute to pollination. However, they were observed to exhibit rejection of cotton pollen by scraping pollen grains from their body and discarding them, prior to returning to their hives. Pollen gatherers collected only small, loose pellets from cotton. SEM studies showed that cotton pollen grains were the largest of all pollen commonly collected by bees in my investigations, and that they also had large spines. It is likely that these characteristics make cotton pollen unattractive to honeybees. Another possible reason for the unattractiveness of cotton flowers was the presence of pollen beetles, Carpophilus aterrimus, in them. I conducted a series of studies to determine the role of pollen beetles in pollination of cotton. I found that they did not contribute to pollination at low levels; at high populations they damaged flowers (with ≥ 10 beetles / flower, no flowers set bolls); and that honeybees, when given the choice, avoid flowers with pollen beetles. Because the insecticide fipronil was commonly used in Australian cotton at flowering time, and because I had some experience of its toxic effects against honeybees in my field investigations, I conducted a series of laboratory and potted plant bioassays, using young worker bees. The studies confirmed its highly toxic nature. I recorded an acute dermal LD50 of 1.9 ng / bee, and an acute oral LC50 of 0.62 ppm. Fipronil’s residual toxicity also remained high for an extended period in both laboratory and potted plant trials. For example, when applied to cotton leaves in weather-exposed potted cotton plants, it took 25 d and 20 d for full and half recommended rates of fipronil, respectively, to become non- toxic to honeybees. I had previously investigated whether a shorter period of exposure of cotton plants to honeybees would contribute adequately to increased yield, and concluded that a 10 d window within a 25 d flowering period would contribute 55% of the increase in total weight of bolls contributable to honeybee pollination, but only 36% of the increase in weight of lint. Given the highly residual activity of fipronil I recorded, the only opportunity for an insecticide-free period during flowering would be at its commencement. I concluded that, while there is evidence that honeybees can contribute to increased cotton yield in Bt cotton in Australia, this is unlikely with the continued use of fipronil at flowering.

Made available in DSpace on 2015-12-10T14:24:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-09-01. Added 1 bitstream(s) on 2015-12-10T14:31:07Z : No. of bitstreams: 1 000854121.pdf: 838077 bytes, checksum: e0a3ad06314a00e5970e1e35f0033845 (MD5)
A cotonicultura apresenta destaque no cenário mundial, pois emprega tecnologia avançada representada por maquinários modernos e técnicos com grande experiência de campo, elevados investimentos e pela diversidade de utilização da pluma. O objetivo deste trabalho foi avaliar o algodoeiro cv. FMT 701 em função de sistemas de aplicação de subdoses de glifosato e regulador de crescimento. O delineamento experimental foi o de blocos ao acaso em esquema fatorial 6x2 com 4 repetições, perfazendo um total de 48 parcelas, compostas por: a- número de aplicações da subdose do glifosato (20 g e.a. (equivalente ácido) ha -1 ): (zero, uma, duas, três, quatro e cinco), aplicadas via foliar respectivamente aos 40; 40 e 50; 40, 50 e 60; 40, 50, 60 e 70 e 40, 50, 60, 70 e 80 dias após emergência (d.a.e.) das plantas; e b- manejo do regulador de crescimento em aplicação foliar (50 g i.a. (ingrediente ativo - cloreto de mepiquat) ha -1 ) sendo por aplicações de forma parcelada (3 dias após a aplicação da subdose do glifosato) ou de forma única aos 70 d.a.e. (nas parcelas que não receberam a subdose); e sem aplicação. A cultivar de algodão FMT 701 submetida a duas aplicações da subdose do glifosato apresenta maior crescimento em altura e de concentração de Mg foliar além de maior número de capulhos por planta e produtividade de algodão em caroço quando associado ao cloreto de mepiquat. A utilização do regulador de crescimento proporciona aumento do diâmetro do caule, concentração de N e Mg foliar e índice SPAD de clorofila, e diminui o comprimento de ramos reprodutivos. Cinco aplicações da subdose de glifosato associadas à utilização do cloreto de mepiquat proporcionam redução de altura de plantas, produtividade e índice de micronaire no algodoeiro
The cotton crop has featured on the world stage because employs advanced technology, represented by modern machinery and technicians with great field experience, high investments and the diversity of the plume use. The objective of this study was to evaluate the cotton cv. FMT 701 in function of application systems of glyphosate low dose and growth regulator. The experimental design was a randomized block in 6x2 factorial with four replications, totaling 48 plots with: a- number of glyphosate low dose applications (20 g a.e. (acid equivalent) ha -1 ): (zero, one, two, three, four and five), foliar applied respectively to 40; 40 and 50; 40, 50 and 60; 40, 50, 60, 70 and 40, 50, 60, 70 and 80 days after emergence of plants (d.a.e.); and b- managing of the growth regulator for foliar application (50 g a.i. (active ingredient - mepiquat chloride) ha -1 ) being split application form (3 days after application of glyphosate low dose) or only way at 70 d.a.e. (in plots that didn't receive a low dose); and without application. The cotton cultivar FMT 701 submitted to two applications glyphosate low dose has increased the height and leaf Mg concentration and greater number of bolls per plant and cotton seed yield when combined with mepiquat chloride. The use of the growth regulator provides increased stem diameter, leaf Mg and N concentration and SPAD chlorophyll content, and decreases the length of reproductive branches. Five applications of glyphosate low dose associated with the use of mepiquat chloride provide height plant reduction, yield and micronaire index in the cotton crop

Orientador: Enes Furlani Junior
Banca: Luiz Henrique Carvalho
Banca: Edivaldo Cia
Banca: Marco Eustáquio de Sá
Banca: Fernando Tadeu de Carvalho
Resumo: A cotonicultura apresenta destaque no cenário mundial, pois emprega tecnologia avançada representada por maquinários modernos e técnicos com grande experiência de campo, elevados investimentos e pela diversidade de utilização da pluma. O objetivo deste trabalho foi avaliar o algodoeiro cv. FMT 701 em função de sistemas de aplicação de subdoses de glifosato e regulador de crescimento. O delineamento experimental foi o de blocos ao acaso em esquema fatorial 6x2 com 4 repetições, perfazendo um total de 48 parcelas, compostas por: a- número de aplicações da subdose do glifosato (20 g e.a. (equivalente ácido) ha -1 ): (zero, uma, duas, três, quatro e cinco), aplicadas via foliar respectivamente aos 40; 40 e 50; 40, 50 e 60; 40, 50, 60 e 70 e 40, 50, 60, 70 e 80 dias após emergência (d.a.e.) das plantas; e b- manejo do regulador de crescimento em aplicação foliar (50 g i.a. (ingrediente ativo - cloreto de mepiquat) ha -1 ) sendo por aplicações de forma parcelada (3 dias após a aplicação da subdose do glifosato) ou de forma única aos 70 d.a.e. (nas parcelas que não receberam a subdose); e sem aplicação. A cultivar de algodão FMT 701 submetida a duas aplicações da subdose do glifosato apresenta maior crescimento em altura e de concentração de Mg foliar além de maior número de capulhos por planta e produtividade de algodão em caroço quando associado ao cloreto de mepiquat. A utilização do regulador de crescimento proporciona aumento do diâmetro do caule, concentração de N e Mg foliar e índice SPAD de clorofila, e diminui o comprimento de ramos reprodutivos. Cinco aplicações da subdose de glifosato associadas à utilização do cloreto de mepiquat proporcionam redução de altura de plantas, produtividade e índice de micronaire no algodoeiro
Abstract: The cotton crop has featured on the world stage because employs advanced technology, represented by modern machinery and technicians with great field experience, high investments and the diversity of the plume use. The objective of this study was to evaluate the cotton cv. FMT 701 in function of application systems of glyphosate low dose and growth regulator. The experimental design was a randomized block in 6x2 factorial with four replications, totaling 48 plots with: a- number of glyphosate low dose applications (20 g a.e. (acid equivalent) ha -1 ): (zero, one, two, three, four and five), foliar applied respectively to 40; 40 and 50; 40, 50 and 60; 40, 50, 60, 70 and 40, 50, 60, 70 and 80 days after emergence of plants (d.a.e.); and b- managing of the growth regulator for foliar application (50 g a.i. (active ingredient - mepiquat chloride) ha -1 ) being split application form (3 days after application of glyphosate low dose) or only way at 70 d.a.e. (in plots that didn't receive a low dose); and without application. The cotton cultivar FMT 701 submitted to two applications glyphosate low dose has increased the height and leaf Mg concentration and greater number of bolls per plant and cotton seed yield when combined with mepiquat chloride. The use of the growth regulator provides increased stem diameter, leaf Mg and N concentration and SPAD chlorophyll content, and decreases the length of reproductive branches. Five applications of glyphosate low dose associated with the use of mepiquat chloride provide height plant reduction, yield and micronaire index in the cotton crop
Doutor

According to several scientific reports, climate change will have an impact on water provision and thus agriculture, which depends on soil moisture for plant survival. India is a country that is heavily dependent on agriculture as a source of income. One of the country’s future challenges is securing water for irrigation. Cotton in India is an important cash crop which is grown under high evapotranspirative demand, using about 15% of the national water resources, making the crop vulnerable to changes in water availability.

The purpose of this study is to evaluate the resilience of cotton production with regards to water availability and pesticide use in Punjab and Andhra Pradesh. Three aspects of resilience: latitude, resistance and precariousness has been used to analyse three variables, precipitation, irrigation and pesticide in order to understand how these cotton growing systems are going to be affected by climate change. By bringing together existing data from several scientific reports and governmental websites, assumptions could be made whether these systems are resilient or if they are reaching a threshold. The results show that the cotton growing regions of Punjab are highly vulnerable when it comes to water provision in the region and that they might be reaching a threshold. Changes in climate are predicted to affect precipitation and temperature in the area, which in time might ultimately affect water resources in the region. Groundwater depletion and water logging are already prevailing problems in the area where almost all cotton production is irrigated. Cotton farmers in Andhra Pradesh are struggling with pest infestation which induces them to overconsume pesticides, affecting not only water quality in the area, but also farmers’ livelihood. It is likely that climate change will not minimize the outbreaks; on the contrary it might benefit some pests, which might increase the consumption of pesticide in the region. Coastal districts are more exposed to extreme weather which can harm cotton cultivation.

In the fall of 1999 an experiment was conducted to measure the effect of CGA- 362622, halosulfuron (Permit), glyphosate (Roundup Ultra) and Pyrithiobac (Staple) on purple nutsedge. Five rates of Permit (0.25, 0.375, 0.495, 0.75 and 1.0 oz a.i./A), three rates of CGA-362622 (3.035, 4.047, and 6.07 g a.i./A), and a single rate each of Roundup Ultra (0.75 lb a.e./A), Staple (1.5 oz a.i./A), Staple + Bueno 6 (2 lb a.i./A), and Staple + Fusilade (0.25 lb a.i./A) were applied either once or twice to field populations of purple nutsedge. Efficacy of each treatment was measured in three ways: phytotoxicity (stunting, chlorosis and/or necrosis) ratings were assigned to each plot (0 being no injury and 10 indicating death), the number of green leaves were counted on 3 large ($8 leaves) and 3 small (≤4 leaves) plants per plot at various times after treatment, and the amount of regrowth after the herbicide treatments was assessed. All of the herbicide treatments caused stunting, induced chlorosis and necrosis, and were fairly effective in controlling nutsedge plants treated at or before the 4-leaf growth stage. Only Permit and CGA-362622 effectively controlled plants treated at the 8-leaf growth stage after one application. The other four herbicides required two applications to obtain effective control. For the regrowth parameter parameters, Permit, CGA-362622 and Roundup Ultra effectively controlled regrowth, but the Staple, Staple + Bueno 6 and the Staple + Fusilade treatments did not control regrowth. Two applications of Permit at the .495 oz a.i./A or greater rates, Roundup Ultra (0.75 lb a.e./A) and 1 or 2 applications of the 6.070 g a.i./A rate of CGA-362622 controlled nutsedge with respect to all measured regrowth parameters and may be the best choices for controlling purple nutsedge.

Thesis (Ph.D.)--University of Western Sydney, 2008.
A thesis submitted to the University of Western Sydney, College of Health and Science, Centre for Plant and Food Science, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliography.

Made available in DSpace on 2014-06-11T19:22:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-01-29Bitstream added on 2014-06-13T18:48:48Z : No. of bitstreams: 1 souza_fs_me_botfca.pdf: 722599 bytes, checksum: bddbe2539a4c9c196d08d8670e432f38 (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O presente trabalho teve por objetivo avaliar o comportamento de plantas de algodão submetidas à aplicação de doses de cloreto de mepiquat e precipitações pluviais ocorrendo em diferentes momentos após a aplicação do produto. Procurou-se ainda desenvolver um método simples de estimativa da dose do produto a ser aplicada. Os tratamentos foram constituídos de três doses do regulador a base de cloreto de mepiquat (PIX®): 7,5, 15,0 e 22,5 g ha-1 e seis intervalos de tempo para aplicação de chuva simulada de 20 mm de intensidade: 0, 1, 3, 6, 12 e 24 horas, mais um tratamento sem a aplicação de chuva. Foram utilizados vasos de 12 litros de capacidade e seis sementes pré-germinadas com posterior desbaste para duas plantas por vaso. O delineamento experimental utilizado foi o inteiramente casualizado com quatro repetições. Os parâmetros avaliados foram: altura de plantas, número de ramos reprodutivos, massa de matéria seca, retenção de estruturas reprodutivas (coleta de estruturas reprodutivas e estruturas perdidas) e área foliar. Os resultados mostraram que o efeito do regulador foi prejudicado pela ocorrência de chuva nos momentos mais próximos a sua pulverização. As maiores doses mostraram ter efeito mais significativo nos parâmetros de crescimento avaliados, mostrando que chuvas ocorridas em momentos mais próximos após a pulverização causam maior comprometimento da ação do regulador nas plantas de algodão. É possível calcular a dose de regulador a ser aplicada conhecendo-se a altura atual das plantas.
The research had the objective to evaluate the behavior of cotton plants submitted to the application of doses of Mepiquat Chloride and precipitations happening in different times after the application of the product. A tentative for developing a simple method for estimating the dose of the product that would be applied was tried. The treatments were constituted of three doses of the growth regulator, mepiquat chloride (PIX®): 7,5, 15,0 and 22,5 g ha-1 and six time intervals for the application of simulated rain of 20mm of intensity: 0, 1, 3, 6, 12 and 24 hours, and one treatment without rain. Plots of 12 liters of capacity and six pre-germinated seeds were used with subsequent rough-hewing for two plants per plot. The experimental design used was the completely randomized with four replications. The parameters analyzed were: height of plants, number of reproductive branches, weight of dry matter, collecting of reproductive structures and lost structures, and leaf area. The results showed that the effect of the growth regulator was harmed by the rain occurrence in the closest moments of the application of the growth regulator. It was possible to calculate the regulator dose to be applied knowing the actual height of the plants.

Orientador: Ciro Antonio Rosolem
Banca: João Domingos Rodrigues
Banca: Ederaldo José Chiavegato
Resumo: O presente trabalho teve por objetivo avaliar o comportamento de plantas de algodão submetidas à aplicação de doses de cloreto de mepiquat e precipitações pluviais ocorrendo em diferentes momentos após a aplicação do produto. Procurou-se ainda desenvolver um método simples de estimativa da dose do produto a ser aplicada. Os tratamentos foram constituídos de três doses do regulador a base de cloreto de mepiquat (PIX®): 7,5, 15,0 e 22,5 g ha-1 e seis intervalos de tempo para aplicação de chuva simulada de 20 mm de intensidade: 0, 1, 3, 6, 12 e 24 horas, mais um tratamento sem a aplicação de chuva. Foram utilizados vasos de 12 litros de capacidade e seis sementes pré-germinadas com posterior desbaste para duas plantas por vaso. O delineamento experimental utilizado foi o inteiramente casualizado com quatro repetições. Os parâmetros avaliados foram: altura de plantas, número de ramos reprodutivos, massa de matéria seca, retenção de estruturas reprodutivas (coleta de estruturas reprodutivas e estruturas perdidas) e área foliar. Os resultados mostraram que o efeito do regulador foi prejudicado pela ocorrência de chuva nos momentos mais próximos a sua pulverização. As maiores doses mostraram ter efeito mais significativo nos parâmetros de crescimento avaliados, mostrando que chuvas ocorridas em momentos mais próximos após a pulverização causam maior comprometimento da ação do regulador nas plantas de algodão. É possível calcular a dose de regulador a ser aplicada conhecendo-se a altura atual das plantas.
Abstract: The research had the objective to evaluate the behavior of cotton plants submitted to the application of doses of Mepiquat Chloride and precipitations happening in different times after the application of the product. A tentative for developing a simple method for estimating the dose of the product that would be applied was tried. The treatments were constituted of three doses of the growth regulator, mepiquat chloride (PIX®): 7,5, 15,0 and 22,5 g ha-1 and six time intervals for the application of simulated rain of 20mm of intensity: 0, 1, 3, 6, 12 and 24 hours, and one treatment without rain. Plots of 12 liters of capacity and six pre-germinated seeds were used with subsequent rough-hewing for two plants per plot. The experimental design used was the completely randomized with four replications. The parameters analyzed were: height of plants, number of reproductive branches, weight of dry matter, collecting of reproductive structures and lost structures, and leaf area. The results showed that the effect of the growth regulator was harmed by the rain occurrence in the closest moments of the application of the growth regulator. It was possible to calculate the regulator dose to be applied knowing the actual height of the plants.
Mestre

This study considered runoff of pesticides from cotton fields using a rainfall simulator. The Australian cotton industry is based on clay soils on low sloping land and uses a hill-furrow surface geometry. These conditions are unlike those in many studies of pesticide dissipation, sorption and runoff and there has been little previous research into hydrology, erosion and pesticide runoff in the industry. Of particular interest was to characterise runoff of different pesticides, clarity the underlying factors controlling pesticide runoff, and investigate management practices to reduce runoff of pesticides with contrasting chemical properties, for the conditions found in the cotton industry. Runoff behaviour of different pesticides has often been studied independently. Separating the inherent behaviour of the pesticide and the conditions of the study, and comparing pesticides, is difficult. Runoff concentrations depend on the hydrology and erosion of each site, and particularly on the timing of runoff events after spraying. These factors can be controlled and/or measured using a rainfall simulator. Furthermore, multi-residue pesticide analysis now allows study of a number of pesticides simultaneously, so that their behaviour can be compared directly for the same site conditions and management options. Review of the literature indicated that a large variation in pesticide runoff is related to application rate, formulation and placement, and dissipation, and that only a shallow soil surface layer contributes pesticides to runoff. In this study, the analysis was simplified by only considering placement on the soil surface (i.e. not on plant foliage) of liquid/emulsified formulations and soilincorporated sprays. A simple conceptual framework was used to compare and integrate data from simulated rainfall studies of pesticides used in the cotton industry and contrast them with data in the literature. By comparing pesticide runoff to the concentration in the soil surface at the start of rain, one set of factors, those that occur before the rainfall event - application and dissipation, were separated from those that occur during the rainfall event - leaching and runoff extraction. To complete the picture of how pesticides get from the spray nozzle to the edge of a field in runoff, four main areas were considered - dissipation, runoff extraction, sediment-water partitioning and management. Dissipation data were collected at four sites across the cotton growing areas and runoff data at three of these sites, on soils with medium to high clay content. Some 14 pesticides were studied, including the insecticide endosulfan (a- and (3-isomers and the breakdown product endosulfan sulfate) at all sites. Dissipation studies concentrated on the 3-6 weeks after application, when concentrations are highest, and on the soil surface layer that contributes pesticides to runoff. For practical reasons, soil concentrations were measured in the 0-25mm soil depth. While the major emphasis was on dissipation of endosulfan from soil and crop residues, several organophosphate (OP) insecticides (chlorpyrifos, dimethoate and profenofos) and a range of herbicides (fluometuron, metolachlor, prometryn, diuron, pendimethalin, pyrithiobac sodium) were also studied. Dissipation in the 0-25mm soil depth followed first-order exponential decay, with one phase, for most pesticides. However, large initial losses occurred for several of the insecticides studied: 35-55% for endosulfan, but only when applied at higher temperatures, most likely due to volatilisation. Initial losses of 50-75% occurred for the OP’s, dimethoate (inconsistently), chlorpyrifos and profenofos. Dissipation half-lives in the 0-25mm soil depth (after initial losses) were 6-20 days for endosulfan (total of a-, (3- and sulfate), 8-13 days for organophosphates, and 13-32 days for herbicides, a-endosulfan consistently dissipated more rapidly than p-endosulfan, but the two isomers were affected differently by site and/or climatic factors. Dissipation of endosulfan was similar for ULV and EC formulations, for bare and covered soil and for band and blanket sprays, but was somewhat slower after two applications. Only small amounts of endosulfan sulfate formed in dry soils, while more formed in temporarily wet soil, contributing about half the total endosulfan remaining after 30 days. Dissipation in surface 0-25mm soil was more rapid than in 0-50mm soil, but this varied from no effect for the rapidly dissipated OP’s to 1.6 times faster for endosulfan, and varied according to Koc for the herbicides. Herbicides with lower Koc dissipated faster in the surface layer than those with higher Koc, due to greater downward movement. Downward movement decreased the apparent halflife in the 0-25mm soil and increased the apparent half-life in 0-50mm soil. Half-lives in 0-25mm soil were considerably lower than published ‘selected’ values. Dissipation of endosulfan was consistent with studies in other warmer climates. The shallow depth of soil studied (which enhanced downward movement) and application on the surface contributed to this more rapid dissipation. The results are consistent with observations that “runoff available residues” dissipate more rapidly than generally expected for bulk soil. Endosulfan dissipated rapidly (e.g. 75-90%) from crop residue cover (wheat or cotton trash) within the first day after spraying, apparently a result of volatilisation. Half-lives for endosulfan on crop residues after the initial loss were similar to those in bare and covered soils. The data indicate that a benefit of retaining crop residues on the soil surface, in addition to reducing runoff and sediment losses, is that it intercepts and dissipates the endosulfan more rapidly than when sprayed onto soil. Runoff extraction was investigated, in a simple empirical analysis, by comparing concentration in soil (mg/kg) before rain and event average concentration in runoff (pg/L), using data from three rainfall simulator studies in cotton fields, for 14 pesticides, and from the literature. The ratio of runoff to soil concentrations, or the linear regression slope fitted through the origin, was termed the runoff extraction ratio (ER0). The pesticides varied widely in solubility (0.003-700,OOOmg/L) and ranged from strongly (DDE, KD~ 15,000) to weakly sorbed (fluometuron, dimethoate, pyrithiobac sodium, KD <30). Runoff extraction behaviour from bare soil was remarkably consistent for pesticides of widely different properties. Total concentrations in runoff of each pesticide were closely related to concentrations in the soil (0-25mm) before rain, generally with a similar relationship for all pesticides and sites, over four orders of magnitude range in concentrations. As a first approximation, concentration in runoff (pg/L) = 28 times concentration in soil (mg/kg), (or Ero = 28). Runoff extraction was also somewhat similar for dissolved N and P, and organic N. Ero values were not related to partition coefficients (KP) measure in runoff. However, runoff extraction did decrease with time after spraying and was lower for aged DDE and trifluralin at one site. This is considered to relate to lower concentrations in the surface few mm of soil (c.f. 0-25mm soil) over time. ERO values were similar for the slopes studied (0.2-4%), for long and short plots, and for banded and blanket spray plots. Runoff extraction was reduced where cover reduces sediment concentration. Runoff extraction was significantly lower for a weakly sorbed pesticide (dimethoate) in only one instance and not for a range of other weakly sorbed pesticides at the other sites. Concentrations in the water and sediment phases in runoff, and in sediment (mg/kg), were also linearly related to soil concentrations for pesticides of similar KP, but extraction in two phases varied according to normal partitioning (Eqn 5-5). The sediment concentration in runoff (10-60 g/L from bare plots) had a secondary effect on ER0, and only affected ERO when sediment concentration was low (i.e. with cover). This is because higher sediment concentrations were associated with lower concentrations in the sediment (mg/kg), due to greater desorption and decreasing physical enrichment. Less physical enrichment (due to size-selective sediment sorting) occurred than observed on coarser textured soil (e.g. enrichment ratio up to 8), with enrichment ratios mostly less than 1.0 (due to desorption) and no greater than 2.0. For all pesticides, the concentration in sediment (mg/kg) was within a factor of about two of the soil concentration adjusted for desorption using the normal partitioning equation. Organic carbon and clay were also only slightly enriched in sediment, despite considerable deposition in the furrows. This is because the soils eroded as aggregates (due to low sand and high clay content), and because coarser sediment had greater concentrations of sorbed pesticides than finer sediment, the opposite of what is normally expected (e.g. where coarser sediment is sand). The notable similarity of runoff extraction ratio for all pesticides in the rainfall simulator studies was probably because (a) the main factor that limit runoff of weakly sorbed chemicals, i.e. leaching from the runoff mixing zone, was ineffective because of low infiltration and ponding of infiltrated water in the shallow tilled layer in the bottom of furrows, (b) sediment concentrations were high enough to ensure transport of strongly sorbed pesticides, and (c) all pesticides had some transport in both the water and sediment phases, diluting the response to sediment load. The concentration of pesticide extracted from soil into runoff appears to be determined by the soil concentration, with, in the absence of significant leaching and with sufficient sediment transport, little differentiation between pesticides of different partition properties. This is partly because, on any plot, the same mass of soil and the same volume of water are involved in mixing, independent of the chemical being considered, and because factors that increase extraction of solutes also tend to increase detachment of sediment. Analysis of published runoff data for a range of pesticides in US croplands indicated similar average runoff extraction to the rainfall simulator studies in Australian cotton fields. However, runoff extraction was higher for much more erosive conditions (e.g. cultivated 10-15% slopes) and lower for low erosion conditions (furrow irrigation on low sloping fields in California). Runoff extraction was similar for this latter case (i.e. ERO~30) once adjusted to a higher sediment concentration. Analysis of the rainfall simulator and published data presents a conceptual framework where the major drivers of pesticide runoff were separated between (a) application rate and dissipation, described by soil concentration at the start of rain, which accounts for five orders of magnitude differences in runoff concentrations, and (b) runoff extraction during the rainfall event, which varied over a limited range. The first of these factors causes most of the difference in runoff between pesticides. Partition coefficients in runoff (KP) were not affected by cover and wheel traffic treatments even though these treatments had large effects on pesticide runoff concentrations. KP values increased with time after spraying, rapidly in the first few days and more slowly over the next few weeks, for all pesticides. KP values were greater than soil sorption KD values, increasingly so for pesticides of lower sorption. Thus pesticides normally considered weakly sorbed were much more sorbed in sediment than expected, particularly at longer times. Conversely, moderately/strongly sorbed pesticides, such as endosulfan, were less sorbed than expected in the first day or so. Partitioning appeared to be influenced by both time of contact with soil and time of mixing (during rain). The results are conceptually consistent with a two-compartment, bi-phasic (fast-slow) sorption model, with the soil in the runoff-mixing layer under rainfall being a continuous dilution system. The ‘slow’ phase, due to diffusion into less accessible soil domains, leads to increasing partition coefficients with greater time of contact. The short time of mixing means that the water phase is mainly interacting with the ‘fast’ or most accessible fraction, while the ‘slow’ fraction remains in the sediment phase. Percentages in the water phase in runoff, for 14 pesticides, roughly followed a published relationship with solubility, and an empirical relationship with soil sorption Koc values, but only for erosive conditions. These relationships do not reflect the full range in responses that occur due to the likely range of concentrations and organic carbon content of sediment, or the increase in KP with time. Because of lower KP values soon after spraying, less soluble pesticides had 20-45% in water. Conversely, a few days/weeks after spraying, more soluble pesticides had only 60-80% in water. Thus all pesticides tended to have a ‘foot in each camp’ and some potential for management using erosion control practices. It is an over simplification to expect ‘percent in water’ to be a characteristic of a pesticide. So long as sediment concentration and KP can be estimated, the percentage in the water phase can be calculated quite simply from first principles (Eqn 5-5) and behaviour for relevant field conditions can be assessed. This equation was used to show that reported values of percentage in the water phase for endosulfan that appeared to conflict (20-95%) and the values from the rainfall simulator plots (15- 45%) are explained by differences in sediment concentration and organic carbon in the studies. A wide range of percentages in water (10-95%) will occur for pesticides with KP of 5-500 (or solubilities -1-100), such as endosulfan, for the range of sediment concentrations and organic carbon that might occur in the environment. Improved practices are needed to minimise soil erosion, and related agrochemical transport, from cotton fields during rain. The most influential practice used in other agricultural industries, that is, retaining crop residues as surface cover, is rarely practiced in the Australian cotton industry. Therefore two options available to cotton growers, namely retention of surface cover and controlling wheel traffic, were evaluated using simulated rain on a well-aggregated black Vertosol. Increasing cover (0-60%) resulted in decreasing runoff, soil loss and sediment concentration. Runoff and soil loss were reduced by an order of magnitude with about 50% cover and by a small amount with notraffic. Cover and no traffic combined gave least runoff and soil loss. Pesticide transport in runoff was also reduced strongly by retaining on-ground cover and somewhat reduced by avoiding prior wheel traffic. With 45-60% cover, concentrations were reduced 5-fold for a-, |3- and total endosulfan; halved for endosulfan sulfate, trifluralin and DDE, and unchanged for prometryn. Cover had more effect on endosulfan because cover intercepted and dissipated the sprayed endosulfan, reducing concentrations in surface soil. Cover greatly reduced total pesticide losses (g/ha) because cover reduced runoff and soil loss considerably. With 45-60% cover, total losses were reduced by 90-98%. No-traffic gave 40% lower losses, and enhanced the effect of cover, but did not prevent large pesticide losses from bare plots. Cover provided more control of more soil-sorbed pesticides (endosulfan, trifluralin and DDE). Control of the less sorbed prometryn was largely due to cover reducing runoff. An examination of the practical requirements for maintaining effective cover in cotton farming systems indicated that most of the perceived conflicts with insect, weed and irrigation management could be overcome, although further study is needed. Many of these results have only been possible because of the use of the rainfall simulator, multiresidue pesticide analysis and the availability of sufficient resources. Such opportunities are rare in field research. By allowing an intensive regime of runoff sampling at controlled times after pesticide applications, the study has yielded data with more significance, enabling the conclusions made above regarding the relative behaviour of individual pesticides and their extraction from soil in runoff. The author acknowledges the contributions made by others to this study, but all of the experimental work and the data reported in this thesis were under his control.

Soil is an invaluable finite resource, and it is essential that any changes in soil condition are adequately monitored. In the semi-arid regions of eastern Australia, there has been an expansion of intensive irrigated cotton production, and these regions have also experienced highly variable rainfall patterns in the last decade or so. This combination of climatic and land use changes has the potential to significantly alter soil attributes. This thesis focuses on monitoring the change in several important soil properties – pH, salinity, sodicity, and organic and inorganic carbon – in the semi-arid irrigated cotton-growing district of Hillston, NSW, between 2002 and 2015. Rather than using traditional digital soil mapping techniques, this study focuses on using bi- and multi-variate linear mixed models, and two-step mixture models to model and map soil properties in space and time. The linear mixed models were particularly advantageous for monitoring changes in soil properties as they can account for correlation in space and time, and improve the sensitivity of detecting statistically significant changes. As traditional laboratory methods of measuring certain soil properties can be expensive and laborious, this study also focused on using visible near infrared (VisNIR) spectroscopic techniques to rapidly predict exchangeable sodium percentage (ESP), organic carbon (SOC) content, and inorganic carbon (SIC) content. Various degrees and extents of soil change were observed during the study period in both the top and sub soil. This included an acidification trend in some areas, a contrasting shift in electrical conductivity (EC) under differing land uses, an increase in soil ESP under irrigated land uses, an increase in SOC content at some locations, and no detectable change in SIC content. Overall, it was clear that fluctuating rainfall patterns and agricultural management practices had a notable impact on the degree and direction of changes in soil properties.

Made available in DSpace on 2015-12-10T14:22:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-08-11. Added 1 bitstream(s) on 2015-12-10T14:28:50Z : No. of bitstreams: 1 000854087.pdf: 1102727 bytes, checksum: 35cab368e6353c3c228fc80132d40f32 (MD5)
Devido à expansão da cotonicultura, pesquisas com reguladores de crescimento e subdoses de herbicidas estão sendo desenvolvidas para incrementar a produtividade da cultura. O objetivo do presente trabalho foi avaliar o efeito das subdoses de 2,4-D e cloreto de mepiquat nas características vegetativas e produtivas de dois cultivares de algodão. O experimento foi conduzido durante o período de novembro de 2012 a maio de 2013 e novembro de 2013 a maio de 2014. O delineamento experimental foi o de blocos ao acaso em um esquema fatorial 6 x 2 x 2, com 4 repetições, totalizando 96 parcelas, perfazendo 24 tratamentos: a testemunha e cinco subdoses do herbicida 2,4-D: 0,68; 1,36; 2,04; 2,72 e 3,40 g equivalente ácido (e.a.) por ha -1, com e sem aplicação de cloreto de mepiquat na dose 200 mL ha -1 nas cultivares FMT 701 e Fibermax 966 de algodoeiro. Aplicou-se as subdoses de 2,4-D aos 45 dias após a emergência da planta (d.a.e.) e o regulador de crescimento aos 70 d.a.e. Constatou-se que a utilização do regulador de crescimento (cloreto de mepiquat) na dose 200 mL ha -1 foi eficiente no controle do desenvolvimento da planta em relação a variável altura de planta no dois anos de estudo. Para o cultivar de porte baixo, a aplicação das subdoses crescente de 2,4-D proporciona um incremento na altura de planta. Com o aumento das subdoses de 2,4-D, ocorre um incremento no número de estruturas reprodutivas para o cultivar FMT 701. A aplicação de subdoses de 2,4-D na faixa de 1,75 a 1,90 g e. a. ha -1 propicia um aumento de produtividade de algodão em caroço para a cultivar FMT 701. Para a cultivar Fibermax 966 a subdose de 1,75 propicia um incremento na produtividade de algodão em caroço. A cultivar FMT 701 obteve maior altura de planta, diâmetro do caule, quantidade de ramos reprodutivos, capulhos por planta e produtividade de algodão em caroço comparado com a cultivar Fibermax 966 nos dois anos agrícolas
Due to expansion of cotton production, research with growth regulators and sublethal rates of herbicide are being developed to improve levels of crop productivity. The aim of this study was to evaluate the effect of sublethal rates of dichlorophenoxyacetic acid and mepiquat chloride on vegetative and productive characteristics of two cultivar of cotton plant. The experiment was conducted during the growing season of 2012/2013 and 2013/2014. The experimental design was a randomized completely blocks design in a factorial system 6 x 2 x 2 with 4 replications, consisting 96 plots, with the amount of twenty four treatments: one control and five rates of 2,4-D: 0.68, 1.36, 2.04 2.72 and 3.40 g equivalent acid (e.a) by ha -1, with and without application of mepiquat chloride in the level 200 mL ha-1 in the cultivar FMT 701 and Fibermax 966 cotton. Applied to the doses of 2,4-D at 45 days after plant emergence (d.a.e.) and the growth regulator to 70 d.a.e. The result showed that the use of the growth regulator (mepiquat chloride) at a dose 200 mL ha -1 was effective in controlling plant development in relation to plant height on the two-year study. For the small size of cultivar, the application of increasing doses of 2,4-D provides an increase in plant height. With increasing doses of 2,4-D, there is an increase in the number of reproductive structures for cultivating FMT 701. The application doses of 2,4-D in the range of 1.75 and 1.90 g. The. ha - 1 provides an increase of seed cotton productivity to grow FMT 701. To cultivate Fibermax 966 to sub-dose of 1.75 provides an increase in cotton productivity in seed. Cultivar FMT 701 obtained the highest plant height, stem diameter, number of reproductive branches, bolls per plant and cotton productivity in seed compared with the cultivar Fibermax 966 in both years

Orientador: Enes Furlani Júnior
Banca: Marcelo Andreotti
Banca: Ederaldo José Chiavegato
Resumo: Devido à expansão da cotonicultura, pesquisas com reguladores de crescimento e subdoses de herbicidas estão sendo desenvolvidas para incrementar a produtividade da cultura. O objetivo do presente trabalho foi avaliar o efeito das subdoses de 2,4-D e cloreto de mepiquat nas características vegetativas e produtivas de dois cultivares de algodão. O experimento foi conduzido durante o período de novembro de 2012 a maio de 2013 e novembro de 2013 a maio de 2014. O delineamento experimental foi o de blocos ao acaso em um esquema fatorial 6 x 2 x 2, com 4 repetições, totalizando 96 parcelas, perfazendo 24 tratamentos: a testemunha e cinco subdoses do herbicida 2,4-D: 0,68; 1,36; 2,04; 2,72 e 3,40 g equivalente ácido (e.a.) por ha -1, com e sem aplicação de cloreto de mepiquat na dose 200 mL ha -1 nas cultivares FMT 701 e Fibermax 966 de algodoeiro. Aplicou-se as subdoses de 2,4-D aos 45 dias após a emergência da planta (d.a.e.) e o regulador de crescimento aos 70 d.a.e. Constatou-se que a utilização do regulador de crescimento (cloreto de mepiquat) na dose 200 mL ha -1 foi eficiente no controle do desenvolvimento da planta em relação a variável altura de planta no dois anos de estudo. Para o cultivar de porte baixo, a aplicação das subdoses crescente de 2,4-D proporciona um incremento na altura de planta. Com o aumento das subdoses de 2,4-D, ocorre um incremento no número de estruturas reprodutivas para o cultivar FMT 701. A aplicação de subdoses de 2,4-D na faixa de 1,75 a 1,90 g e. a. ha -1 propicia um aumento de produtividade de algodão em caroço para a cultivar FMT 701. Para a cultivar Fibermax 966 a subdose de 1,75 propicia um incremento na produtividade de algodão em caroço. A cultivar FMT 701 obteve maior altura de planta, diâmetro do caule, quantidade de ramos reprodutivos, capulhos por planta e produtividade de algodão em caroço comparado com a cultivar Fibermax 966 nos dois anos agrícolas
Abstract: Due to expansion of cotton production, research with growth regulators and sublethal rates of herbicide are being developed to improve levels of crop productivity. The aim of this study was to evaluate the effect of sublethal rates of dichlorophenoxyacetic acid and mepiquat chloride on vegetative and productive characteristics of two cultivar of cotton plant. The experiment was conducted during the growing season of 2012/2013 and 2013/2014. The experimental design was a randomized completely blocks design in a factorial system 6 x 2 x 2 with 4 replications, consisting 96 plots, with the amount of twenty four treatments: one control and five rates of 2,4-D: 0.68, 1.36, 2.04 2.72 and 3.40 g equivalent acid (e.a) by ha -1, with and without application of mepiquat chloride in the level 200 mL ha-1 in the cultivar FMT 701 and Fibermax 966 cotton. Applied to the doses of 2,4-D at 45 days after plant emergence (d.a.e.) and the growth regulator to 70 d.a.e. The result showed that the use of the growth regulator (mepiquat chloride) at a dose 200 mL ha -1 was effective in controlling plant development in relation to plant height on the two-year study. For the small size of cultivar, the application of increasing doses of 2,4-D provides an increase in plant height. With increasing doses of 2,4-D, there is an increase in the number of reproductive structures for cultivating FMT 701. The application doses of 2,4-D in the range of 1.75 and 1.90 g. The. ha - 1 provides an increase of seed cotton productivity to grow FMT 701. To cultivate Fibermax 966 to sub-dose of 1.75 provides an increase in cotton productivity in seed. Cultivar FMT 701 obtained the highest plant height, stem diameter, number of reproductive branches, bolls per plant and cotton productivity in seed compared with the cultivar Fibermax 966 in both years
Mestre

Made available in DSpace on 2014-06-11T19:31:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-12-17Bitstream added on 2014-06-13T19:21:15Z : No. of bitstreams: 1 funichello_m_dr_jabo.pdf: 263321 bytes, checksum: 745d29c4123310500dd5e9e50d9646ed (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A cultura no algodoeiro abriga uma grande quantidade de insetos que podem causar danos a sua produção. A lagarta Pseudoplusia includens (Walker) mais encontrada na soja, tem se destacado atualmente na região Centro-Oeste do Brasil, devido aos novos sistemas de cultivos sucessivos, soja-algodão. Um dos principais avanços tecnológicos é a disponibilidade de cultivares transgênicas, resistentes para algumas espécies desfolhadoras de insetos-pragas, porém, algumas espécies, consideradas alvo da tecnologia, tem sobrevivido e preocupado produtores. Este trabalho teve como objetivo avaliar os principais aspectos biológicos de P. includens alimentadas com folhas de quatro cultivares de algodoeiro, bem como estudar o efeito da cultivar transgênica NuOPAL, sobre o comportamento, sobrevivência e desenvolvimento do inseto. Além disso, avaliou-se o consumo foliar de lagartas e a atratividade a estas cultivares. Avaliou-se também a distribuição vertical de lagartas de P. includens na cultivar transgênica WideStrike e na sua isolinha comercial FM 993. O delineamento experimental utilizado foi inteiramente casualizado, com quatro tratamentos (cultivares DeltaOPAL, NuOPAL, FM 993 e FM 910), com 30 ou 60 repetições, conforme o experimento. No ensaio de não preferência para alimentação de lagartas, foi utilizado o delineamento inteiramente casualizado, com 10 repetições, com as mesma cultivares. Para a distribuição vertical de lagartas nas plantas das cultivares FM 993 e FM 975 WS foi utilizado delineamento em blocos casualizados em esquema de parcelas subdivididas, com 06 tratamentos (3 terços da planta x 2 faces foliares), e 40 repetições. Os dados obtidos foram transformados em (x+0,5)1/2 e submetidos a Análise de Variância para cada cultivar e as médias dos tratamentos comparadas pelo teste...
The cotton crop has a large number of insects that can damage the production. The caterpillar Pseudoplusia includens (Walker) most commonly found in soybean, has been highlighted today in the Midwest region of Brazil, due to new systems of crop rotation, soybean-cotton. One of the major technological advances is the availability of transgenic cultivars resistant to some species of defoliating insect pests, but some species considered target technology, has survived and concerned farmers. This study aimed to evaluate the main biological aspects P. includens feed by leaves of four cotton cultivars, as well as studying the effect of transgenic NUOPAL cultivar, on behavior, survival and development of the insect. Furthermore, were evaluated the attractiveness and foliar consumption by larvae to the cultivars. Another objective was to evaluate the vertical distribution of larvae of P. includens in transgenic cultivar WideStrike and its isoline commercial FM 993. Were used a completely randomized design, using treatments with cultivars DeltaOPAL, NUOPAL, FM 993 and FM 910, with 60 replicates for the antibiosis experiment. In the test of non-preference for feeding caterpillars, was used completely randomized design with 10 replicate with the same cultivars. For the vertical distribution was used as a randomized block design in a split-plot, with 06 treatments (3 parts of plants x 2 leaf surface), and 40 replicate. The data were transformed into (x +0.5)1/2 and subjected to analysis of variance and treatments means were compared by Tukey test at 5% probability. The Bt cultivar Bt (Bollgard I) exerts the sort of antibiosis to half of the larval population, extending the larval stage of the survivors. It also reduces the larvae and pupae weight, and provides significantly greater duration period of larval-adult. In testing the non-feeding preference of... (Complete abstract click electronic access below)

Orientador: Antônio Carlos Busoli
Coorientador: Arlindo Leal Boiça Junior
Banca: Júlio Cesar Guerreiro
Banca: Marcos Doniseti Michelotto
Banca: Odair Aparecido Fernandes
Banca: Nilza Maria Martinelli
Resumo: A cultura no algodoeiro abriga uma grande quantidade de insetos que podem causar danos a sua produção. A lagarta Pseudoplusia includens (Walker) mais encontrada na soja, tem se destacado atualmente na região Centro-Oeste do Brasil, devido aos novos sistemas de cultivos sucessivos, soja-algodão. Um dos principais avanços tecnológicos é a disponibilidade de cultivares transgênicas, resistentes para algumas espécies desfolhadoras de insetos-pragas, porém, algumas espécies, consideradas alvo da tecnologia, tem sobrevivido e preocupado produtores. Este trabalho teve como objetivo avaliar os principais aspectos biológicos de P. includens alimentadas com folhas de quatro cultivares de algodoeiro, bem como estudar o efeito da cultivar transgênica NuOPAL, sobre o comportamento, sobrevivência e desenvolvimento do inseto. Além disso, avaliou-se o consumo foliar de lagartas e a atratividade a estas cultivares. Avaliou-se também a distribuição vertical de lagartas de P. includens na cultivar transgênica WideStrike e na sua isolinha comercial FM 993. O delineamento experimental utilizado foi inteiramente casualizado, com quatro tratamentos (cultivares DeltaOPAL, NuOPAL, FM 993 e FM 910), com 30 ou 60 repetições, conforme o experimento. No ensaio de não preferência para alimentação de lagartas, foi utilizado o delineamento inteiramente casualizado, com 10 repetições, com as mesma cultivares. Para a distribuição vertical de lagartas nas plantas das cultivares FM 993 e FM 975 WS foi utilizado delineamento em blocos casualizados em esquema de parcelas subdivididas, com 06 tratamentos (3 terços da planta x 2 faces foliares), e 40 repetições. Os dados obtidos foram transformados em (x+0,5)1/2 e submetidos a Análise de Variância para cada cultivar e as médias dos tratamentos comparadas pelo teste... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The cotton crop has a large number of insects that can damage the production. The caterpillar Pseudoplusia includens (Walker) most commonly found in soybean, has been highlighted today in the Midwest region of Brazil, due to new systems of crop rotation, soybean-cotton. One of the major technological advances is the availability of transgenic cultivars resistant to some species of defoliating insect pests, but some species considered target technology, has survived and concerned farmers. This study aimed to evaluate the main biological aspects P. includens feed by leaves of four cotton cultivars, as well as studying the effect of transgenic NUOPAL cultivar, on behavior, survival and development of the insect. Furthermore, were evaluated the attractiveness and foliar consumption by larvae to the cultivars. Another objective was to evaluate the vertical distribution of larvae of P. includens in transgenic cultivar WideStrike and its isoline commercial FM 993. Were used a completely randomized design, using treatments with cultivars DeltaOPAL, NUOPAL, FM 993 and FM 910, with 60 replicates for the antibiosis experiment. In the test of non-preference for feeding caterpillars, was used completely randomized design with 10 replicate with the same cultivars. For the vertical distribution was used as a randomized block design in a split-plot, with 06 treatments (3 parts of plants x 2 leaf surface), and 40 replicate. The data were transformed into (x +0.5)1/2 and subjected to analysis of variance and treatments means were compared by Tukey test at 5% probability. The Bt cultivar Bt (Bollgard I) exerts the sort of antibiosis to half of the larval population, extending the larval stage of the survivors. It also reduces the larvae and pupae weight, and provides significantly greater duration period of larval-adult. In testing the non-feeding preference of... (Complete abstract click electronic access below)
Doutor

No presente estudo, analisam-se os danos ambientais resultantes do cultivo do algodão, provenientes do hiperconsumismo e dos resíduos sólidos têxteis dessa fibra natural de maior representatividade mundial. Em um primeiro momento, analisou-se a Teoria do Risco, traçada como ponto definidor e fundamental para o decorrer do estudo, e apresentada como adequada para embasar a análise dos riscos e danos ambientais causados pela produção do algodão, pelos seus resíduos e pelo hiperconsumismo. Em um segundo passo, trabalha-se sobre as formas de produção do algodão no Brasil, trazendo-se os benefícios do cultivo orgânico, e a abordagem acerca da crescente transgenia na cotonicultura. Aborda-se a intensa utilização de agrotóxicos, dificultando a existência de um ciclo sustentável. Em seguida, foca-se nos impactos ambientais causados pela indústria têxtil, enfatizando-se o tema dos resíduos sólidos têxteis com origem no algodão. O método utilizado é o analítico dedutivo, tendo como fundamento a pesquisa bibliográfica explorativa. Por final, revela-se a e permissibilidade jurídica quando do acolhimento dos métodos tradicionais utilizados no desenvolvimento das lavouras algodoeiras, principalmente quanto ao alto nível de agrotóxicos. Os resíduos têxteis do algodão, da indústria e do consumidor são pouco usados a programas sociais de reaproveitamento, entretanto continuam como problema social, haja vista que a Política Nacional dos Resíduos Sólidos não conduziu a uma solução prática. Reconhece-se que o desleixo com os danos ambientais é imenso na sociedade de risco da modernidade, caracterizada pelo avanço capitalista. A trajetória do hiperconsumo expõe uma conduta centralizada no individualismo social ainda que diante de catástrofes recorrentes.
Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2016-12-09T13:06:59Z No. of bitstreams: 1 Dissertacao Tatiana Lucia Strapazzon Pasinato.pdf: 1631041 bytes, checksum: 4f76fbd7e71fd11aa1cd50bf1aa9c019 (MD5)
Made available in DSpace on 2016-12-09T13:06:59Z (GMT). No. of bitstreams: 1 Dissertacao Tatiana Lucia Strapazzon Pasinato.pdf: 1631041 bytes, checksum: 4f76fbd7e71fd11aa1cd50bf1aa9c019 (MD5) Previous issue date: 2016-12-09
In the present study, the environmental damages caused by the cultivation of cotton from the hyperconsumerism and solid textile residues of this natural fiber of greater world-wide importance are analyzed. At first, we analyzed the Risk Theory, drawn as a defining and fundamental point for the course of the study, and presented as adequate to support the analysis of the environmental risks and damages caused by the production of cotton, its residues and hyperconsumption . In a second step, we work on the ways of producing cotton in Brazil, bringing the benefits of organic cultivation, and the approach to growing cotton-growing transgenics. It addresses the intense use of pesticides, making difficult the existence of a sustainable cycle. Next, it focuses on the environmental impacts caused by the textile industry, emphasizing the theme of textile solid waste from cotton. The method used is the deductive analytic, based on the exploratory bibliographical research. Finally, it reveals the legal and legal permissibility when hosting the traditional methods used in the development of cotton crops, especially as regards the high level of pesticides. Textile waste from cotton, industry and consumers is little used for social reuse programs; however, they remain a social problem, since the National Solid Waste Policy did not lead to a practical solution. It is recognized that neglect of environmental damage is immense in the risk society of modernity characterized by capitalist advancement. The trajectory of hyperconsumption exposes a behavior centered on social individualism even in the face of recurrent disasters.

Dans la zone cotonnière au Mali-sud, les différentes études menées expliquent la croissance des effectifs du cheptel bovin par une sous-exploitation des troupeaux par les éleveurs. L'objectif de la thèse est donc de faire un diagnostic sur l'exploitation du cheptel bovin dans la zone cotonnière au Mali-Sud et identifier les contraintes à l'exploitation du troupeau. La méthodologie de recherche a combiné l'approche zootechnique et sociologique pour analyser les pratiques et les décisions d'exploitation des troupeaux des éleveurs. L'utilisation d'un modèle démographique a permis de mesurer la sensibilité du taux de productivité aux différents paramètres démographiques. Le taux d'exploitation nette du troupeau estimé a été de 0,08 / an. Ce taux comparé au taux de 0,11 / an de la productivité numérique du cheptel montre qu'il n'y a pas de sous-exploitation du troupeau bovin. Les processus d'exploitation des animaux impliquent plusieurs décideurs. Cependant, les différentes structures organisationnelles et décisionnelles ne constituent pas une entrave à l'exploitation des animaux. Le besoin monétaire est la principale raison de la vente d'animaux pour faire face aux dépenses de la famille. Les taux d'exploitation et d'importation d'animaux sont en lien avec la taille du troupeau et les comportements des familles. Le taux d'exploitation est lié à la productivité du troupeau. L'amélioration de la productivité passe par une amélioration de la reproduction et une augmentation de la proportion de femelles reproductrices dans le troupeau
In the cotton-growing area of Southern Mali, the different studies conducted explain the growth of the cattle herds' size by the under off-take of the herds by the breeder. The objective of the thesis is therefore to make a diagnosis on the off-take of the cattle herds in the cotton-growing area of Southern Mali and to identify the constraints of the herd off-take. The research methodology combined zoo technical and sociological approach to analyze the practices and the off-take decisions of the breeder's herds. The use of a demographic model permitted to measure the sensitivity of the productivity rate to the different demographic parameters. The valued off-take rate of the herd was of 0.08 year-1. This rate compared to the rate of 0.11 year-1 of the numeric productivity of livestock shows that there is not under off-take of the cattle herds. The processes of animal's off-take imply several decision-makers. However, the different organizational structures and decision don't constitute a hindrance to the animal's off-take. The monetary need is the main reason of animal's sale to face the family's expenses. The rates of off-take and in-take of animals are tie with the herd size and the behaviors of the families. The off-take rate is related to the productivity of the herd. The productivity improvement passes by the reproduction improvement and the proportion of reproductive females in the herd

Made available in DSpace on 2014-06-11T19:30:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04-23Bitstream added on 2014-06-13T19:40:05Z : No. of bitstreams: 1 souza_fs_dr_botfca.pdf: 850813 bytes, checksum: b2ea4ed97c12f6f0ca8cce6267ea054f (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O presente trabalho teve por objetivo avaliar plantas de algodão submetidas a reguladores de crescimento em função das condições ambientais e de absorção dos produtos quando aplicados ou não com adjuvante vegetal. No primeiro experimento foram avaliadas plantas de algodão submetidas ao regulador à base de Cloreto de Mepiquat e regimes de temperatura dia/noite de 25/15, 32/22 e 39/29 °C. O delineamento experimental utilizado foi o inteiramente casualizado com cinco repetições. Foram avaliados parâmetros de crescimento, retenção de estruturas reprodutivas, fisiológicos e anatômicos. No segundo experimento os tratamentos foram constituídos de uma dose de regulador à base de Cloreto de Mepiquat e chlormequat e correspondente a 15,0 g ha 1 do princípio ativo, aplicado com e sem adjuvante. As plantas foram submetidas à lâmina de chuva correspondente a 30 mm após 0; 1,5; 3; 6; 12 e 24 horas da aplicação do regulador, mais um tratamento sem chuva. O delineamento experimental foi o em blocos casualizados com quatro repetições. Foram avaliados parâmetros de crescimento, estruturas reprodutivas, reposição do regulador lavado pela chuva e concentração do regulador na planta. Além disso, foram realizados testes paralelos que visaram determinar a concentração dos produtos nas plantas e o comportamento das plantas em condições de campo submetidas à lavagem do regulador. O uso de adjuvante siliconado contribuiu de maneira significativa para a permanência e/ou absorção dos produtos pelas plantas de algodão; o melhor regime de temperatura para o desenvolvimento das plantas de algodão, bem como para que o regulador à base de Cloreto de Mepiquat possa ter sua ação expressa da melhor forma, foi a de 32/22°C e a reposição do regulador inicialmente aplicado e lavado por chuva se faz necessária para que as plantas tenham o seu crescimento controlado, o que melhora todo o sistema de produção.
This research had as objective to evaluate cotton plants submitted to plant growth regulators as affected by environmental and uptake conditions when applied with or without adjuvant. In the first experiment, cotton plants were evaluated when they were submitted to mepiquat chloride and temperature regimes, day/night, of 25/15, 32/22 and 39/29 °C. The experimental design was the completely randomized with five replications. Growth, physiological, reproductive structure retention and anatomical parameters were evaluated related to the plant growth regulator uptake. In the second experiment, treatments were constituted by one rate of plant growth regulator mepiquat chloride and chlormequat chloride of 15 g ha-1 of the active ingredient, applied with and without adjuvant on cotton plants. Plants were submitted to simulated rainfall of 30 mm after 1; 1,5; 3; 6; 12 and 24 hours after plant growth regulators application, plus a treatment without rainfall. The experimental design was in randomized blocks with four replications. The parameters evaluated were: plant growth, reproductive structures, reposition of the plant growth regulator washed by the rainfall and concentration of the plant growth regulators in the plant. Besides, parallel tests were carried out which had as objective to determinate the concentration of the products in the plants and plant growth in field conditions submitted to plant growth regulator wash. A silicon adjuvant contributes in a significant way for the product permanence and/or uptake by the cotton plants. The most adequate temperature regime for plant development, as well as, for mepiquat chloride plant growth regulator to express its action was 32/22°C and the reapplication of the regulator rate initially applied and washed by rainfall was necessary, so the plants could have their growth controlled, what optimizes the whole production system.

Orientador: Ciro Antonio Rosolem
Banca: João Domingos Rodrigues
Banca: Enes Furlani Junior
Banca: Celso Jamil Marur
Banca: Luiz Henrique Carvalho
Resumo: O presente trabalho teve por objetivo avaliar plantas de algodão submetidas a reguladores de crescimento em função das condições ambientais e de absorção dos produtos quando aplicados ou não com adjuvante vegetal. No primeiro experimento foram avaliadas plantas de algodão submetidas ao regulador à base de Cloreto de Mepiquat e regimes de temperatura dia/noite de 25/15, 32/22 e 39/29 °C. O delineamento experimental utilizado foi o inteiramente casualizado com cinco repetições. Foram avaliados parâmetros de crescimento, retenção de estruturas reprodutivas, fisiológicos e anatômicos. No segundo experimento os tratamentos foram constituídos de uma dose de regulador à base de Cloreto de Mepiquat e chlormequat e correspondente a 15,0 g ha–1 do princípio ativo, aplicado com e sem adjuvante. As plantas foram submetidas à lâmina de chuva correspondente a 30 mm após 0; 1,5; 3; 6; 12 e 24 horas da aplicação do regulador, mais um tratamento sem chuva. O delineamento experimental foi o em blocos casualizados com quatro repetições. Foram avaliados parâmetros de crescimento, estruturas reprodutivas, reposição do regulador lavado pela chuva e concentração do regulador na planta. Além disso, foram realizados testes paralelos que visaram determinar a concentração dos produtos nas plantas e o comportamento das plantas em condições de campo submetidas à lavagem do regulador. O uso de adjuvante siliconado contribuiu de maneira significativa para a permanência e/ou absorção dos produtos pelas plantas de algodão; o melhor regime de temperatura para o desenvolvimento das plantas de algodão, bem como para que o regulador à base de Cloreto de Mepiquat possa ter sua ação expressa da melhor forma, foi a de 32/22°C e a reposição do regulador inicialmente aplicado e lavado por chuva se faz necessária para que as plantas tenham o seu crescimento controlado, o que melhora todo o sistema de produção.
Abstract: This research had as objective to evaluate cotton plants submitted to plant growth regulators as affected by environmental and uptake conditions when applied with or without adjuvant. In the first experiment, cotton plants were evaluated when they were submitted to mepiquat chloride and temperature regimes, day/night, of 25/15, 32/22 and 39/29 °C. The experimental design was the completely randomized with five replications. Growth, physiological, reproductive structure retention and anatomical parameters were evaluated related to the plant growth regulator uptake. In the second experiment, treatments were constituted by one rate of plant growth regulator mepiquat chloride and chlormequat chloride of 15 g ha-1 of the active ingredient, applied with and without adjuvant on cotton plants. Plants were submitted to simulated rainfall of 30 mm after 1; 1,5; 3; 6; 12 and 24 hours after plant growth regulators application, plus a treatment without rainfall. The experimental design was in randomized blocks with four replications. The parameters evaluated were: plant growth, reproductive structures, reposition of the plant growth regulator washed by the rainfall and concentration of the plant growth regulators in the plant. Besides, parallel tests were carried out which had as objective to determinate the concentration of the products in the plants and plant growth in field conditions submitted to plant growth regulator wash. A silicon adjuvant contributes in a significant way for the product permanence and/or uptake by the cotton plants. The most adequate temperature regime for plant development, as well as, for mepiquat chloride plant growth regulator to express its action was 32/22°C and the reapplication of the regulator rate initially applied and washed by rainfall was necessary, so the plants could have their growth controlled, what optimizes the whole production system.
Doutor

The effects of cotton leaf crumple disease on components of yield and on symptom expression were examined for cotton inoculated at five growth stages. As a result of virus infection, the total leaf area was reduced and significant reductions in yield were observed, regardless of plant age at time of inoculation. Yield reductions resulted from a smaller number of bolls set and/or a decrease in boll weight. Foliar symptoms were associated with plants inoculated at all five growth stages, but were observed sooner and were more severe for plants inoculated at the 2-3, 5-8, and 8-10 leaf stages than those inoculated at the 14-16 or 18-20 leaf stages.

High Volume Instrument (HVI) classing of eighteen cotton varieties grown at several elevations in southeastern Arizona are compared by location in this paper. Data presented herein would indicate that elevation does not affect fiber length nor strength, these factors are more a function of variety and management. Micronaire values were seen to be lower at the higher elevations and this was felt to be a function of lower maturity level because of reduced growing season coupled with production of fine fibered New Mexico acalas. This report also contains HVI values on lint from 47 varieties of short staple cotton grown on the Safford Agricultural Center during the 1989 season.

The computer program AZSCHED, with weather data obtained from AZMET, was used to schedule irrigations for a yield trial of early season Upland Cotton (DPL 20) at the Maricopa Agricultural Center. Cotton lint yields were compared between plots from five treatments involving five irrigation efficiencies (50 %, 65 %, 75 %, 90% and 110 %). As in previous years, a potassium bromide tracer was applied to select areas in each plot to monitor the movement of water and nitrates down the soil profile. The total amount of fertilizer as nitrogen applied in two split applications and sidedressed was 100 #/a. The total amount of water applied to the plots ranged from 42.7" for 50% to 26.6" for 110% (deficit) irrigation efficiency. The plots were harvested on October 5, 1993. There was a significant difference in lint yield between the irrigation efficiency treatments. The 50% irrigation efficiency treatment produced 1190 # lint /acre while the 110% efficiency produced 883 # lint /acre.

A field trial was conducted at the Maricopa Agricultural Center to observe the effects of four irrigation efficiencies (65 %, 75 %, 85 %, and 95 %) on the lint yield produced from two upland cotton varieties (DP 5415 and DP 5816). Nitrogen requirements for the crop were determined using pre -season soil samples and in-season petiole samples with data collected from crop monitoring at weekly intervals. AZSCHED was used as a guide to the irrigation timing and amount of water applied during the season. The irrigation efficiency did not have an effect on the lint yield of the cotton crop regardless of variety, but there was a significant difference in yield between the varieties. Lint yields ranged from 1165 #/acre to 1299 #/acre for DP 5415 and 869 #/acre to 986 #/acre for DP 5816.

A field trial was conducted at the Maricopa Agricultural Center to observe the effects of four irrigation efficiencies (65%, 75%, 85%, and 95%) on the lint yield produced from two upland cotton varieties (DP 5409 and SG 125). Nitrogen requirements for the crop were determined using pre-season soil samples and in-season petiole samples in conjuction with crop monitoring data collected at weekly intervals. AZSCHED was used as a guide to the irrigation timing and amount of water applied during the season. The actual irrigation efficiencies obtained were less than what was targeted. The end season results were 59, 62, 62, and 68 %, respectively. This is due in part to the inherent inefficiency of irrigations in the early season. This year there was a lint yield response to the different irrigation efficiencies, but no difference in yield between the two varieties. Lint yields were significantly lower in the 95 % irrigation efficiency plots. Lint Yields ranged from 1058 and 1109 # lint/acre (DP5409 and SG125 at 95 %) to 1358 and 1353 # lint/acre (SG 125 and DP5409 at the 85 % irrigation efficiency).

The computer program AZSCHED, with weather data obtained from AZMET, was used to schedule irrigations for a yield trial of Upland Cotton (DPL 90) at the Maricopa Agricultural Center. Cotton lint yields were compared between plots from eight treatments involving the combination of two irrigation efficiencies (70% and 90%), two nitrogen fertilizer placements (sidedressed and broadcast), and two phosphate fertilizer applications (0#/a and 50#/a). A potassium bromide (KBr) tracer was applied to select areas in each plot prior to the first irrigation. The total amount of fertilizer as nitrogen applied in split applications to both the sidedressed and broadcast plots was 120 #/a. The average amount of water applied to the plots were 33.5" for 70 % efficiency and 26.9" for 90% efficiency. Soil samples from each KBr applied plot were taken to a depth of 10' for analysis of bromide and nitrate to determine the depth of water movement through the soil profile. The plots were harvested on October 7, 1992. This year there was no significant difference in lint yield between any of the treatments: irrigation efficiencies, nitrogen placement, or phosphorous application.

The computer program AZSched, with weather data obtained from AzMet, was used to schedule irrigation for a yield trial of Upland Cotton (DPL 90) at the Maricopa Agricultural Center in 1991. Cotton lint yields were compared between plots from four treatments involving the combination of two irrigation efficiencies (70% and 90 %) and two nitrogen fertilizer applications (broadcast and sidedress). The amount of nitrogen fertilizer applied to the broadcast plots was 145# N /A. One hundred thirty pounds NIA was applied to the sidedressed plots. A potassium bromide tracer was applied to select areas in each plot at the time of initial fertilization. Soil samples from each plot were taken to a depth of 10' for analysis of bromide and nitrate to determine the depth of water movement through the soil profile. Irrigation amounts averaged 42.8" for 70% efficiency and 36.7" for 90% efficiency. No significant difference in lint yield was noticed between the two nitrogen fertilizer applications, but significant differences existed between the two irrigation efficiencies.

A field trial was conducted at the Maricopa Agricultural Center to observe the effects of four irrigation efficiencies (65%, 75%, 85 %, and 95 %) on the lint yield produced from two upland cotton varieties (DP 5409 and SG 125). Nitrogen requirements for the crop were determined using pre-season soil samples and in-season petiole samples in conjunction with crop monitoring data collected at weekly intervals. AZSCHED was used as a guide to the irrigation timing and amount of water applied during the season. The actual irrigation efficiencies obtained were less than what was targeted. The end season results were 60, 66, 72, and 74 %, respectively. The low efficiencies are due in part to the inherent inefficiency of irrigations in the early season. There was no lint yield response to the different irrigation efficiencies, and no difference in yield between the two varieties. Lint Yields ranged from 1146 # lint/acre (SG125 at 75 %) to 925 # lint /acre (SG 125 at the 95 % irrigation efficiency).

Rain grown cotton production is typified by significant climate variability with water limitation a focal constraint. Ensuing system exposure to climate risk results in substantial variability in production area, lint yield, lint quality and profit outcomes. Climate risk management involves manipulating multiple agronomic management and genetic solutions simultaneously; moderating existing limitations to reach the system water-limited yield potential. Such strategies can introduce management diversity to the farming system, but lack application agility, have added implementation costs and system rain-dependency often precludes their implementation. This thesis informs discourse regarding novel adaptive management opportunities utilising plant growth regulators (PGRs), to enable in-season responsive management of limitations under dynamic climatic conditions, offset climate variability and improve system resilience. Ensuing outcomes being increased farm-gate profits, through provision of improved crop resource use efficiencies, lint yield and quality outcomes, with less annualised variability. A scarcity of detailed information exists regarding cotton crop and plant responses to exogenous Gibberellin, Cytokinin and Gibberellin biosynthesis inhibiting PGR treatment scenarios, notably in early growth and under water-limited rain grown production contexts. Understanding these responses can enable future development of frameworks for strategic, predictive applications within rain grown cotton systems.

Experimental insecticides were evaluated for control of lygus bugs relative to commercial standards in cotton. These products were also evaluated for activity towards whiteflies and pink bollworms. CGA293343 was not effective when used as a side-dress material at layby, but was effective toward whiteflies, and towards lygus at higher foliar rates. Regent, Vydate and Mustang + Thiodan were highly effective for lygus control, while EXP61096A and Mustang alone performed poorly. Against whiteflies, CGA293343, Acetamiprid, and Mustang + Thiodan were most efficacious, while Mustang alone and with Thiodan were most effective towards pink bollworms.

This experiment was conducted to quantify herbicide carry -over effects on wheat, after plowing the cotton down with conventional and reduced tillage systems. Cotton layby applications of cyanizine, diuron, and prometryne at 1.5 lbs/Ac active ingredient did not result in wheat yields that were significantly different from the untreated checks within any of the tillage systems.

Neither Tracer nor Proclaim appeared to be effective pink bollworm materials whether applied at day or night. However against cotton leafperforator, both Tracer and Proclaim provided sufficient control. Although all three formulations of Karate equally provided statistically significant pink bollworm control, it was not commercially acceptable. Shortening the spray interval from 7 to 4 days may have helped alleviate this problem. None of the Karate formulations evaluated appeared to offer outstanding cotton leafperforator control.

Based on acreage, broccoli is the third largest vegetable crop in Yuma County, after head lettuce, and romaine. It generates over $36 000000 a year. Efforts are continuously made by both seed industry and growers to grow better varieties that respond to consumers’ choice. Selection of newly adapted varieties is made based on agronomic performance as well as commercial value. Stand uniformity, disease resistance, color, head shape, and head size are among characteristics that are evaluated. The objective of this demonstration trial is to evaluate the characteristics of new varieties grown under standard cultural practices. Twelve varieties were tested at Yuma Agricultural Research Center. No incidence of disease was observed and the overall evaluation rating was greater than 4 indicating that all varieties tested will do well under similar growing conditions and planting date. Significant head diameter and plant height were observed among varieties tested.