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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Assessing farmers’ willingness-to-way for improved common bean seed varieties in Malawi : a case study of Kasungu and Dedza districts

Munthali, Grace Timanyechi January 2013 (has links)
Common beans are one of the most important food and cash crops for most Malawians. The insufficient production of the crop in the country coupled with low yields has made scientists give much interest to the crop so that they can address the constraints to the productivity problems. In this regard, breeders have been engaged in the development and release of improved varieties of common beans which in most cases are disease resistant, high yielding, drought resistant, and fast cooking. Therefore it is the interest of this study to find the reasons why productivity of the crop is still low despite the release of the improved varieties. The study adopted contingent valuation (CV), a method frequently used to assess willingnessto- pay of people for non-market goods or services and this was applied to assess farmer’s willingness-to-pay for the new improved bean seed varieties which are high yielding. Double bounded dichotomous choice with an open ended follow-up format was used to obtain the household’s willingness-to-pay. In addition; the study reviewed the existing dissemination channels of bean seed to make recommendations with regard to seed supply. Descriptive statistics from the 132 households interviewed shows that the structural constraints to seed acquisition are compounded by farmers’ poverty. Otherwise, most farmers are aware of the existence of improved varieties of common bean seed and perceive that with the use of this seed, productivity can improve hence willing to pay for the good. The study is 95% confident that mean price farmers are willing to pay for improved common bean seed is between MK 527.78 and MK 591.92. Three major existing informal dissemination channels of bean seed were discovered in the study areas. Therefore there is a need for government to work in collaboration with NGOs towards ensuring a formal supply system of bean seed characterised by vertically organised production and dissemination of tested and approved seed varieties, and using strict quality control rules, so that farmers can be assured of accessing improved seed varieties. This will increase the nation’s food security. / Dissertation (MSc Agric)--University of Pretoria, 2013. / gm2014 / Agricultural Economics, Extension and Rural Development / unrestricted
2

THE EFFECTS OF COOKED COMMON BEANS ON DSS-INDUCED COLITIS IN MICE

ZHANG, PENGLIHUI CLAIRE 13 September 2012 (has links)
This thesis is an investigation of the effects of whole beans, with different levels of phenolics level, on colonic inflammation in mice. C57BL/6 male mice were fed a basal diet (BD) supplemented with or without 20% bean flour for 3 weeks. Colitis was induced by 2% dextran sulphate sodium (DSS) in mice drinking water. Phenolic determinations of the bean flours revealed that within each pair of beans, the darker bean had higher phenolic content and antioxidant activity compared to the lighter one. In addition, only coloured beans had anthocyanin. When bean were consumed both prior to and during DSS cycle, the mice experienced both disease attention and aggravation. However, when bean consumption was limited to prior to DSS induction only, mice had reduced colitis upon later DSS induction. Overall, findings suggest that the effects of bean may differ depending on the timing of consumption. / Agriculture and Agri-Food of Canada, Ontario Ministry of Agriculture and Rural Affairs
3

Product attributes and consumer preference: the case of common beans in Zambia

Atilola, Bolanle January 1900 (has links)
Master of Science / Department of Agricultural Economics / Amanor-Boadu, Vincent / Beans play a major role in addressing malnutrition and poverty in Africa. Hence, several studies have been conducted over the last two decades on beans attributes in various African countries, including Zambia. The similarity of these studies is their emphasis on the importance of including consumer preferences in the beans supply chain. This study attempts to contribute to informing the bean supply chain about bean attributes and consumer characteristics influencing beans consumption so that downstream stakeholders can effectively seize the embedded opportunities in the bean supply chain. Data used in this study were obtained from 900 surveyed households in Lusaka, Zambia and analyzed using a logit model. The study evaluated three attributes of beans: gravy quality; cooking time; and grain size. In addition, it assessed the price of beans associated with these attributes. The study sought to determine how these attributes influenced consumer preference for specific color beans. Results show that gravy quality, cooking time and price are important bean attributes influencing consumer preference for purple, mixed yellow and yellow bean while grain size has no statistically significant effect. The study also found that gender, education, and employment status of the household head or person purchasing food for the household, as well as the household’s child dependency ratio, dual household income, residential area and perception of the bean food group’s importance to consumers’ nutritional security were statistically significant in their effect on preference for purple, mixed yellow and yellow beans. The study’s results contribute to downstream stakeholders’ efforts to improve their own decisions in identifying the market segments to engage in. For example, bean breeders, producers, and traders might optimize limited resources available for their activities by investing in products that promise large markets to use volume to overcome any price disadvantage regarding profitability. Similarly, they may also invest in high-value low volume products that could also provide them with acceptable profitability. The option used would depend on their location and their own resource situation.
4

Expanding pulse production in Mozambique : identifying constraints and new strategies

Gungulo, Ana Lidia January 2013 (has links)
Pulses (common beans and cowpeas) provide a major alternative source of protein, and the rapid rise in food prices has led to an increase in the consumption of inexpensive pulses. The slow growth in pulse production has, however, led to a decline in availability. Thus, to overcome this decline in production, this study concern in expanding pulse production in Mozambique by using the agricultural research survey known as TIA. In addition, this study identified and analysed the critical drivers influencing production, as well as constraints and opportunities to expand pulse production in Mozambique. In studying the participation of smallholder farmers in pulse markets, the Heckman two-step approach was applied to avoid sample selection bias. In the first step a Probit model was estimated to capture the household’s decision of whether or not to participate in the market. The second step comprised of an OLS estimation to determine the significance of variables that contribute to the level of pulse sold. At national level, results indicate that the majority of households receive price information, but few households receive information on fertilizers and improved seed use. Most households also have poor access to credit and improved extension services, and low levels of membership of agricultural associations. A very small percentage of household farmers are engaged in pulse production, with male farmers more dedicated to the production of common beans and female farmers more dedicated to the production of cowpeas. In terms of market participation, the results reveal that female-headed households are less likely to participate in pulse markets. The critical factors that discourage entry into the pulse market are distance to the market and yield loss. The factors that give incentives to smallholders to participate in the pulse market are land size, price information and pulse price. The trade volume of common beans is relatively high and is affected by land size, pulse price and price information. In contrast, the trade volume of cowpeas is highly affected by bicycle ownership and ownership of livestock for animal traction. Cowpea prices also have a positive effect on the volume of cowpeas sold. Yield loss is a major factor that negatively affects the pulse trade, while land size has a negative effect on the volume of cowpeas sold. Land availability and price information provide good opportunities, in Mozambique, for expanding pulse production. The expansion of pulse production is however constrained by household access to public goods and services such as extension services, credit and membership to an agricultural association. Moreover, the expansion of pulse production in the country is also constrained by the absence of the use of productive technologies such as improved seed and fertilizer. Based on the results of the study, the recommendations are to expand extension services, improve access to improved technology, facilitate access to agricultural finance, and improve infrastructure and storage facilities. This would facilitate and give incentive to smallholder to expanding pulse production in Mozambique. / Dissertation (MSc Agric)--University of Pretoria, 2013. / gm2014 / Agricultural Economics, Extension and Rural Development / unrestricted
5

Avaliação agronômica da disponibilização de nitrogênio à cultura de feijão sob sistema de semeadura direta. / Agronomic evaluation of nitrogen availability to common bean crop carried out under no tillage system.

Carvalho, Eraldo Augusto de 04 February 2003 (has links)
A combinação de nove tratamentos (T) foi utilizada com o objetivo de fazer uma avaliação agronômica da disponibilização de nitrogênio (N) na produção de feijão, quando inoculado com Rhizobium leguminosarum bv. Phaseoly (RL), cobalto (Co) e molibdênio (Mo), conduzidos sob sistema de semeadura direta (SSD). T1 disponibilizou N através do solo, T2 através da inoculação das sementes com RL (400 g por 50 kg de sementes) imediatamente antes da semeadura, T3 através da inoculação das sementes com RL e adubação nitrogenada em cobertura (60 kg.ha -1 ) (ANC60), utilizando como fonte de N o nitrato de amônio (NA) contendo 33% de N, T4 através inoculação das sementes com Co e Mo (116 g.ha -1 ), produto formulado contendo 1,5% de Co e 10,0% de Mo, T5 através da inoculação das sementes com Co e Mo e ANC60, T6 através da inoculação das sementes com Co, Mo e RL, T7 através da inoculação das sementes com Co, Mo e RL e ANC60, T8 através de ANC60, T9 através da adubação mineral na semeadura com NA (20 kg.ha -1 ) e ANC60. A área escolhida localiza-se no município de Piracicaba, SP (22º42'30" Sul e 47º38'30" Oeste) pertencente ao Departamento de Produção Vegetal da Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, onde o SSD vem sendo usado desde 1993, sendo que as culturas implantadas nessa área nunca foram inoculadas com bactérias fixadoras de N. O solo foi amostrado na camada de 0,0-0,2 m anualmente, de 1994 a 1999, mostrando evolução dos atributos químicos do solo. Os parâmetros utilizados na análise foram: número de nódulos, massa de matéria seca de raízes, nódulos, e parte aérea, número de vagens por planta, número de grãos por vagem, massa de 100 grãos, teor de nitrogênio na planta, índice de utilização de nitrogênio (IUN), coeficientes técnicos e custo de produção total, índice de lucratividade (IL) e rendimento de grãos (Rg). Os resultados evidenciaram que o T7 é uma alternativa para disponibilizar N à cultura, dentro do SSD, obtendo o maior Rg. O SSD foi eficiente na manutenção do teor de matéria orgânica no solo, mas não foi eficiente para suprir totalmente a demanda da planta por N, evidenciando a necessidade da adoção de métodos alternativos para incrementar sua disponibilidade no SSD. / To evaluate the nitrogen (N) availability to common bean grain yield under no tillage system (SSD) after inoculation with Rhizobium leguminosarum bv. phaseoly (RL), cobalt (Co) and molybdenum (Mo), nine treatments (T) were used. T1 supplied N from the soil, T2 supplied N through the inoculation of the seed prior to sowing with RL (400 g per 50 kg of seeds), T3 supplied N through the inoculation of the seed prior to sowing with RL and additional N was also added using a top dressing with 60 kg.ha -1 of ammonium nitrate (NA) with 33% of N (ANC60), T4 supplied N through inoculation of the seed prior to sowing with Co and Mo (116 g.ha -1 ) using a formulated product containing Co (1.5%) and Mo (10.0%), T5 supplied N through inoculation of the seed prior to sowing with Co and Mo and ANC60, T6 supplied N through inoculation of the seed prior to sowing with Co and Mo and RL, T7 supplied N through inoculation of the seed prior to sowing with Co and Mo and RL and ANC60, T8 supplied N through using a top dressing, T9 supplied N using NA in the sowing (20 kg.ha -1 ) and ANC60. The field experiment was carried out at Crop Science Department, Esalq, University of São Paulo, Piracicaba, Brazil (22°42'30" South and 47° 38' 30" West), where the SSD has been practiced since 1993, and the crop had never been inoculated with N fixing bacteria. The soil was sampled annually at 0.0 to 0.2 m depth, from 1993 to 1999, showing evolution in the soil chemical attributes. The following agronomic parameters related to common bean crop were used for statistical analysis: the number of nodules, roots and nodules dry biomass, shoot dry biomass, number of pods per plant and grains per pod, and 100 grains mass, the plant nitrogen content, the nitrogen utilization index (IUN), the technical crop production coefficients, the total production cost, the profitability index (IL) and grain yield (Rg). The results showed that T7 was an alternative to make nitrogen available to common bean crop inside SSD, reaching the best productivity. No tillage system was efficient in the maintenance of the soil organic matter, but it was not efficient enough to supply the total demand of the plant for nitrogen, showing the need of alternative methods adoption to increment its availability to the system.
6

Avaliação agronômica da disponibilização de nitrogênio à cultura de feijão sob sistema de semeadura direta. / Agronomic evaluation of nitrogen availability to common bean crop carried out under no tillage system.

Eraldo Augusto de Carvalho 04 February 2003 (has links)
A combinação de nove tratamentos (T) foi utilizada com o objetivo de fazer uma avaliação agronômica da disponibilização de nitrogênio (N) na produção de feijão, quando inoculado com Rhizobium leguminosarum bv. Phaseoly (RL), cobalto (Co) e molibdênio (Mo), conduzidos sob sistema de semeadura direta (SSD). T1 disponibilizou N através do solo, T2 através da inoculação das sementes com RL (400 g por 50 kg de sementes) imediatamente antes da semeadura, T3 através da inoculação das sementes com RL e adubação nitrogenada em cobertura (60 kg.ha -1 ) (ANC60), utilizando como fonte de N o nitrato de amônio (NA) contendo 33% de N, T4 através inoculação das sementes com Co e Mo (116 g.ha -1 ), produto formulado contendo 1,5% de Co e 10,0% de Mo, T5 através da inoculação das sementes com Co e Mo e ANC60, T6 através da inoculação das sementes com Co, Mo e RL, T7 através da inoculação das sementes com Co, Mo e RL e ANC60, T8 através de ANC60, T9 através da adubação mineral na semeadura com NA (20 kg.ha -1 ) e ANC60. A área escolhida localiza-se no município de Piracicaba, SP (22º42'30" Sul e 47º38'30" Oeste) pertencente ao Departamento de Produção Vegetal da Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, onde o SSD vem sendo usado desde 1993, sendo que as culturas implantadas nessa área nunca foram inoculadas com bactérias fixadoras de N. O solo foi amostrado na camada de 0,0-0,2 m anualmente, de 1994 a 1999, mostrando evolução dos atributos químicos do solo. Os parâmetros utilizados na análise foram: número de nódulos, massa de matéria seca de raízes, nódulos, e parte aérea, número de vagens por planta, número de grãos por vagem, massa de 100 grãos, teor de nitrogênio na planta, índice de utilização de nitrogênio (IUN), coeficientes técnicos e custo de produção total, índice de lucratividade (IL) e rendimento de grãos (Rg). Os resultados evidenciaram que o T7 é uma alternativa para disponibilizar N à cultura, dentro do SSD, obtendo o maior Rg. O SSD foi eficiente na manutenção do teor de matéria orgânica no solo, mas não foi eficiente para suprir totalmente a demanda da planta por N, evidenciando a necessidade da adoção de métodos alternativos para incrementar sua disponibilidade no SSD. / To evaluate the nitrogen (N) availability to common bean grain yield under no tillage system (SSD) after inoculation with Rhizobium leguminosarum bv. phaseoly (RL), cobalt (Co) and molybdenum (Mo), nine treatments (T) were used. T1 supplied N from the soil, T2 supplied N through the inoculation of the seed prior to sowing with RL (400 g per 50 kg of seeds), T3 supplied N through the inoculation of the seed prior to sowing with RL and additional N was also added using a top dressing with 60 kg.ha -1 of ammonium nitrate (NA) with 33% of N (ANC60), T4 supplied N through inoculation of the seed prior to sowing with Co and Mo (116 g.ha -1 ) using a formulated product containing Co (1.5%) and Mo (10.0%), T5 supplied N through inoculation of the seed prior to sowing with Co and Mo and ANC60, T6 supplied N through inoculation of the seed prior to sowing with Co and Mo and RL, T7 supplied N through inoculation of the seed prior to sowing with Co and Mo and RL and ANC60, T8 supplied N through using a top dressing, T9 supplied N using NA in the sowing (20 kg.ha -1 ) and ANC60. The field experiment was carried out at Crop Science Department, Esalq, University of São Paulo, Piracicaba, Brazil (22°42'30" South and 47° 38' 30" West), where the SSD has been practiced since 1993, and the crop had never been inoculated with N fixing bacteria. The soil was sampled annually at 0.0 to 0.2 m depth, from 1993 to 1999, showing evolution in the soil chemical attributes. The following agronomic parameters related to common bean crop were used for statistical analysis: the number of nodules, roots and nodules dry biomass, shoot dry biomass, number of pods per plant and grains per pod, and 100 grains mass, the plant nitrogen content, the nitrogen utilization index (IUN), the technical crop production coefficients, the total production cost, the profitability index (IL) and grain yield (Rg). The results showed that T7 was an alternative to make nitrogen available to common bean crop inside SSD, reaching the best productivity. No tillage system was efficient in the maintenance of the soil organic matter, but it was not efficient enough to supply the total demand of the plant for nitrogen, showing the need of alternative methods adoption to increment its availability to the system.
7

Tiametoxam em plantas de cana-de-açúcar, feijoeiro, soja, laranjeira e cafeeiro: parâmetros de desenvolvimento e aspectos bioquímicos / Thiamethoxan on sugar cane, common bean, soybean, citrus and coffee plants: parameters of development and biochemical aspects

Pereira, Marcelo Andrade 12 April 2010 (has links)
Inseticidas e fungicidas geralmente são estudados quanto a sua eficiência no controle de pragas e doenças, entretanto podem provocar efeitos fisiológicos pouco conhecidos capazes de influenciar o desenvolvimento das culturas. O tiametoxam é um inseticida sistêmico do grupo dos neonicotinóides, da família nitroguanidina, que atua no receptor nicotínico acetilcolina de insetos, danificando o sistema nervoso dos mesmos, levando-os à morte. Este inseticida, largamente utilizado no controle de pragas iniciais e insetos sugadores, apresenta efeito bioativador, uma vez que mesmo na ausência da pragas, promove aumento em vigor e desenvolvimento nas plantas tratadas. Acredita-se que os efeitos do tiametoxam em plantas são indiretos, pois atuam na expressão dos genes responsáveis pela síntese e ativação de enzimas metabólicas, relacionadas ao crescimento da planta, alterando a produção de aminoácidos e precursores de hormônios vegetais. Existem alguns trabalhos com tiametoxam com o objetivo de verificar seus efeitos no metabolismo e desenvolvimento das plantas, mas os resultados ainda não são claros, evidenciando forte interação entre cultivares, épocas, condições de estresse e disponibilidade de nutrientes. Em função da grande utilização do inseticida tiametoxam na agricultura brasileira, o estudo deste agroquímico, no sentido de alterar o metabolismo e desenvolvimento de plantas, constitui-se de grande importância na agregação de informações à literatura biológica e agronômica. Os objetivos deste trabalho foram verificar o efeito da aplicação de tiametoxam em plantas de cana-de-açúcar, feijoeiro, soja, laranjeira e cafeeiro, em diferentes doses e formas de aplicação (tratamento de sementes, pulverização foliar e aplicação no solo), sobre parâmetros de desenvolvimento (área foliar, massa seca de folhas e raízes, comprimento radicular) e aspectos bioquímicos (teores foliares de nutrientes e atividade enzimática). Os experimentos foram realizados em vasos, no Horto Experimental do Departamento de Ciências Biológicas da ESALQ/USP. Concluiu-se que a aplicação de tiametoxam em pulverização foliar, em cana-deaçúcar, aumenta a área foliar e o comprimento das raízes, amplia a espessura do córtex da raiz, incrementa o diâmetro do cilindro vascular e aumenta o número de metaxilemas; em feijoeiro, em tratamento de sementes, aumenta a área foliar, a massa seca da parte aérea e a atividade da nitrato redutase em folhas e em pulverização foliar aumenta a atividade da nitrato redutase e a atividade da fenilalanina amônia-liase em folhas; em soja, em tratamento de sementes, aumenta a área foliar, massa seca e comprimento das raízes e os teores foliares de cálcio e magnésio, e em pulverização foliar, reduz os teores de fósforo e cálcio, mas aumenta os teores de potássio; em mudas de laranjeira, aplicado no solo, aumenta a área foliar, a massa seca das folhas, a massa seca do caule e ramos e a área foliar média, mas reduz os teores foliares de nitrogênio, fósforo e enxofre; em mudas de café arábica, aplicado na raiz, aumenta o número de folhas, a massa seca de raízes finas e o comprimento das raízes. / Insecticides and fungicides are often studied to their efficiency in controlling pests and diseases, however can cause physiological effects little known that can affect crop growth. Thiamethoxan is a systemic insecticide from the neonicotinoid group, nitroguanidine family, which acts on nicotinic acetylcholine receptor of insects, damaging their nervous system, leading them to death. This insecticide, that is widely used for controlling pests and sucking insects, has bioactivator effect, since even in the absence of pests, promotes an increase in vigor and development in treated plants. It is believed that the effects of thiamethoxan in plants are indirect, because it acts in the genes expression responsible for metabolic enzymes activation and synthesis, related to plant growth, by modifying amino acids and plant hormones precursors production. There is a number of studies with thiamethoxan in the way to determine the effects on metabolism and development of plants, but the results are not clear, showing strong interaction between cultivars, stress conditions and nutrient availability. Due to the wide use of the insecticide thiamethoxan in Brazilian agriculture, the study of this insecticide in order to know the metabolism changes in the plants, brings a great importance in the collection of knowledge to the agronomic and biological literature. The objectives of this study was to evaluate the effect of thiamethoxan on sugar cane, common beans, soy, orange and coffee plants with different doses and forms of application (seed treatment, foliar spray and soil application) on developmental parameters (leaf area, dry mass of leaves and roots, root length) and biochemical aspects (nutrient content and enzymatic activity). The experiments were conducted in pots in the ESALQ / USP, Experimental Field of Biological Sciences Department. It was concluded that the application of thiamethoxan as foliar spray on sugar cane, increases leaf area and root length, increases the thickness of the cortex of the root, increases the diameter of the vascular cylinder and increases the number of vessels; in bean for seed treatment, increases the leaf area, dry mass of shoots and the activity of nitrate reductase in leaves, and foliar spray increases the activity of nitrate reductase and phenylalanine ammonia-lyase in leaves; in soybean, in seeds treatment, increases leaf area, dry weight of roots, root length and foliar calcium and magnesium, and foliar spray, reduces the amount of phosphorus and calcium, but increased levels of potassium; in orange trees, applicated on the soil, increases the leaf area, leaf area average, leaves dry mass, stems and branches dry mass, but reduces the amount of nitrogen, phosphorus and sulfur in the leaf; in arabica coffee seedlings, applied at the root, increases the number of leaves, fine roots dry mass and length of roots.
8

Tiametoxam em plantas de cana-de-açúcar, feijoeiro, soja, laranjeira e cafeeiro: parâmetros de desenvolvimento e aspectos bioquímicos / Thiamethoxan on sugar cane, common bean, soybean, citrus and coffee plants: parameters of development and biochemical aspects

Marcelo Andrade Pereira 12 April 2010 (has links)
Inseticidas e fungicidas geralmente são estudados quanto a sua eficiência no controle de pragas e doenças, entretanto podem provocar efeitos fisiológicos pouco conhecidos capazes de influenciar o desenvolvimento das culturas. O tiametoxam é um inseticida sistêmico do grupo dos neonicotinóides, da família nitroguanidina, que atua no receptor nicotínico acetilcolina de insetos, danificando o sistema nervoso dos mesmos, levando-os à morte. Este inseticida, largamente utilizado no controle de pragas iniciais e insetos sugadores, apresenta efeito bioativador, uma vez que mesmo na ausência da pragas, promove aumento em vigor e desenvolvimento nas plantas tratadas. Acredita-se que os efeitos do tiametoxam em plantas são indiretos, pois atuam na expressão dos genes responsáveis pela síntese e ativação de enzimas metabólicas, relacionadas ao crescimento da planta, alterando a produção de aminoácidos e precursores de hormônios vegetais. Existem alguns trabalhos com tiametoxam com o objetivo de verificar seus efeitos no metabolismo e desenvolvimento das plantas, mas os resultados ainda não são claros, evidenciando forte interação entre cultivares, épocas, condições de estresse e disponibilidade de nutrientes. Em função da grande utilização do inseticida tiametoxam na agricultura brasileira, o estudo deste agroquímico, no sentido de alterar o metabolismo e desenvolvimento de plantas, constitui-se de grande importância na agregação de informações à literatura biológica e agronômica. Os objetivos deste trabalho foram verificar o efeito da aplicação de tiametoxam em plantas de cana-de-açúcar, feijoeiro, soja, laranjeira e cafeeiro, em diferentes doses e formas de aplicação (tratamento de sementes, pulverização foliar e aplicação no solo), sobre parâmetros de desenvolvimento (área foliar, massa seca de folhas e raízes, comprimento radicular) e aspectos bioquímicos (teores foliares de nutrientes e atividade enzimática). Os experimentos foram realizados em vasos, no Horto Experimental do Departamento de Ciências Biológicas da ESALQ/USP. Concluiu-se que a aplicação de tiametoxam em pulverização foliar, em cana-deaçúcar, aumenta a área foliar e o comprimento das raízes, amplia a espessura do córtex da raiz, incrementa o diâmetro do cilindro vascular e aumenta o número de metaxilemas; em feijoeiro, em tratamento de sementes, aumenta a área foliar, a massa seca da parte aérea e a atividade da nitrato redutase em folhas e em pulverização foliar aumenta a atividade da nitrato redutase e a atividade da fenilalanina amônia-liase em folhas; em soja, em tratamento de sementes, aumenta a área foliar, massa seca e comprimento das raízes e os teores foliares de cálcio e magnésio, e em pulverização foliar, reduz os teores de fósforo e cálcio, mas aumenta os teores de potássio; em mudas de laranjeira, aplicado no solo, aumenta a área foliar, a massa seca das folhas, a massa seca do caule e ramos e a área foliar média, mas reduz os teores foliares de nitrogênio, fósforo e enxofre; em mudas de café arábica, aplicado na raiz, aumenta o número de folhas, a massa seca de raízes finas e o comprimento das raízes. / Insecticides and fungicides are often studied to their efficiency in controlling pests and diseases, however can cause physiological effects little known that can affect crop growth. Thiamethoxan is a systemic insecticide from the neonicotinoid group, nitroguanidine family, which acts on nicotinic acetylcholine receptor of insects, damaging their nervous system, leading them to death. This insecticide, that is widely used for controlling pests and sucking insects, has bioactivator effect, since even in the absence of pests, promotes an increase in vigor and development in treated plants. It is believed that the effects of thiamethoxan in plants are indirect, because it acts in the genes expression responsible for metabolic enzymes activation and synthesis, related to plant growth, by modifying amino acids and plant hormones precursors production. There is a number of studies with thiamethoxan in the way to determine the effects on metabolism and development of plants, but the results are not clear, showing strong interaction between cultivars, stress conditions and nutrient availability. Due to the wide use of the insecticide thiamethoxan in Brazilian agriculture, the study of this insecticide in order to know the metabolism changes in the plants, brings a great importance in the collection of knowledge to the agronomic and biological literature. The objectives of this study was to evaluate the effect of thiamethoxan on sugar cane, common beans, soy, orange and coffee plants with different doses and forms of application (seed treatment, foliar spray and soil application) on developmental parameters (leaf area, dry mass of leaves and roots, root length) and biochemical aspects (nutrient content and enzymatic activity). The experiments were conducted in pots in the ESALQ / USP, Experimental Field of Biological Sciences Department. It was concluded that the application of thiamethoxan as foliar spray on sugar cane, increases leaf area and root length, increases the thickness of the cortex of the root, increases the diameter of the vascular cylinder and increases the number of vessels; in bean for seed treatment, increases the leaf area, dry mass of shoots and the activity of nitrate reductase in leaves, and foliar spray increases the activity of nitrate reductase and phenylalanine ammonia-lyase in leaves; in soybean, in seeds treatment, increases leaf area, dry weight of roots, root length and foliar calcium and magnesium, and foliar spray, reduces the amount of phosphorus and calcium, but increased levels of potassium; in orange trees, applicated on the soil, increases the leaf area, leaf area average, leaves dry mass, stems and branches dry mass, but reduces the amount of nitrogen, phosphorus and sulfur in the leaf; in arabica coffee seedlings, applied at the root, increases the number of leaves, fine roots dry mass and length of roots.

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