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Efficiency and productivity measurements to analyze farm-level impacts from adoption of biotechnology enhanced soybeansFunk, Samuel Mahlon January 1900 (has links)
Doctor of Philosophy / Department of Agricultural Economics / Allen M. Featherstone / This study focuses on the productivity and on-farm efficiency impacts of adopting biotechnology enhanced soybeans (BES). Previous research suggests the adoption of BES and subsequent time savings resulted in labor allocation to off-farm employment and reduced on-farm efficiency.
Using continuous panel data for 129 farms enrolled in the Kansas Farm Management Association (KFMA) with production and financial crop records from 1993 through 2011 that also provided information on their BES adoption experience, this study provides estimates on the technical efficiency, cost efficiency, and Malmquist productivity indexes (MI) with decompositions into efficiency change (EC) and technical change (TC) to provide insights on the impacts of adopting BES for set of sample farms.
Using data envelopment analysis to construct nonparametric efficiency frontiers and measurements assuming constant returns-to-scale (CRS) and variable returns-to-scale (VRS) technologies for the farms, this study provides insights on the impact of yield impacts of BES adoption. A biennial Malmquist productivity index (BMI) is developed to consider estimation of the productivity impacts between BES adopters and non-adopters assuming VRS. This analysis used five input categories: Labor, general, direct inputs, maintenance, and energy; and five outputs: corn, soybeans, sorghum, wheat, and other crops.
Tobit regression analysis of the panel of Kansas farms provided evidence of a positive impact from adoption of biotechnology enhanced soybeans on on-farm technical efficiency. Kolmogorov-Smirnov goodness-of-fit distributional hypothesis tests showed significant differences between analyzing the farms under CRS and VRS assumptions. T-tests showed a bias existed when assuming CRS if the true underlying technology was VRS in productivity
analysis. However, there was not a strong statistically significant difference between the distributions of productivity measures from the underlying populations of BES adopters and non-adopters in the sample of Kansas farms.
A revenue-indirect cost efficiency analysis of the sample farms demonstrated that different conclusions were reached under CRS and VRS when considering the differences in the average of the means of estimated efficiency scores and Tobit regression results considering BES adoption. Assuming CRS resulted in positive marginal effects for adopting BES of 0.017 significant at the 5% level. The marginal effect of BES adoption was not statistically significant under VRS.
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Pampa gaúcho: causas e consequências do expressivo aumento das áreas de soja.Pizzato, Fernanda January 2013 (has links)
Este trabalho trata do avanço do cultivo de soja sobre novas áreas na porção sul do estado do Rio Grande do Sul, onde está localizado o Pampa. O objetivo desta pesquisa é identificar e entender as causas e as consequências do expressivo aumento de áreas plantadas de soja no Pampa gaúcho. Para isso, foram definidos municípios que melhor evidenciam esta recente transformação, além do estabelecimento de conceitos chave para o entendimento deste processo e dos responsáveis por tal. Além disso, foi realizado um breve histórico da presença da soja no Rio Grande do Sul, onde a modernização da agricultura e o surgimento das sementes transgênicas tiveram um importante papel para o avanço deste cultivo pelo estado. Com este panorama é feita uma comparação entre o avanço da soja no norte e sul do estado, pelo qual foi possível constatar que a presença de colonos acostumados com a produção em grande escala de trigo no planalto gaúcho favoreceu a implantação do cultivo antes na porção norte do que na sul. O Pampa esteve, por muito tempo, condicionado a uma série de fatores que impossibilitavam o aumento das áreas de lavoura de soja e, só depois do surgimento e da disseminação do Sistema de Plantio Direto, este quadro se modificou. A partir de algumas teorias foram selecionados alguns atores importantes para o entendimento do que vem acontecendo na região do Pampa e, através de entrevistas com produtores e demais atores, nos municípios selecionados, foram constatados alguns resultados da pesquisa como identificação de grande quantidade de produtores vindos de outras regiões do estado e que as compras de máquinas, implementos e insumos são feitas em municípios vizinhos movimentando a economia de centros já consolidados no setor de serviços. Contudo, este trabalho também traça algumas tendências para as regiões produtoras de soja, por exemplo, a busca por nichos de mercado mais rentáveis, seja com a produção de novos cultivos de grãos ou com a produção de orgânicos. / This work approach the advancement of soybean cultivation into new areas in the southern state of Rio Grande do Sul, where is located the Pampa. The objective of this research is to identify and understand the causes and consequences of the significant increase in areas planted to soybeans in Pampa. For this, we defined municipalities that best show this recent transformation, beyond the establishment of key concepts for the understanding of this process and those responsible for such. In addition, there was a brief history of the presence of soy in Rio Grande do Sul, where the modernization of agriculture and the emergence of transgenic seeds had an important role in the advancement of this growing state. With this scenario a comparison is made between the advance of soybeans in northern and south of the state, by which it was established that the presence of farmers accustomed to large-scale production of wheat in the gaucho upland favored the deployment of cultivation before at the north than in the south. The Pampa, has long been conditioned to a number of factors that made it impossible to increase the soybean crop areas and only after the emergence and spread of Tillage System, this frame could be modified. From some theories some key players were selected to the understanding of what is happening in the Pampa region, and through interviews with producers and other actors, from selected municipalities, were found some search results as the identification of large numbers of producers coming other regions of the state and that purchases of machinery, implements and inputs are made in neighboring municipalities moving the economy centers already established in the service sector. However, this paper also outlines some trends for the soybean growing regions, for example, the search for the most profitable market niches, either by producing new varieties of grain or organic production.
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Pampa gaúcho: causas e consequências do expressivo aumento das áreas de soja.Pizzato, Fernanda January 2013 (has links)
Este trabalho trata do avanço do cultivo de soja sobre novas áreas na porção sul do estado do Rio Grande do Sul, onde está localizado o Pampa. O objetivo desta pesquisa é identificar e entender as causas e as consequências do expressivo aumento de áreas plantadas de soja no Pampa gaúcho. Para isso, foram definidos municípios que melhor evidenciam esta recente transformação, além do estabelecimento de conceitos chave para o entendimento deste processo e dos responsáveis por tal. Além disso, foi realizado um breve histórico da presença da soja no Rio Grande do Sul, onde a modernização da agricultura e o surgimento das sementes transgênicas tiveram um importante papel para o avanço deste cultivo pelo estado. Com este panorama é feita uma comparação entre o avanço da soja no norte e sul do estado, pelo qual foi possível constatar que a presença de colonos acostumados com a produção em grande escala de trigo no planalto gaúcho favoreceu a implantação do cultivo antes na porção norte do que na sul. O Pampa esteve, por muito tempo, condicionado a uma série de fatores que impossibilitavam o aumento das áreas de lavoura de soja e, só depois do surgimento e da disseminação do Sistema de Plantio Direto, este quadro se modificou. A partir de algumas teorias foram selecionados alguns atores importantes para o entendimento do que vem acontecendo na região do Pampa e, através de entrevistas com produtores e demais atores, nos municípios selecionados, foram constatados alguns resultados da pesquisa como identificação de grande quantidade de produtores vindos de outras regiões do estado e que as compras de máquinas, implementos e insumos são feitas em municípios vizinhos movimentando a economia de centros já consolidados no setor de serviços. Contudo, este trabalho também traça algumas tendências para as regiões produtoras de soja, por exemplo, a busca por nichos de mercado mais rentáveis, seja com a produção de novos cultivos de grãos ou com a produção de orgânicos. / This work approach the advancement of soybean cultivation into new areas in the southern state of Rio Grande do Sul, where is located the Pampa. The objective of this research is to identify and understand the causes and consequences of the significant increase in areas planted to soybeans in Pampa. For this, we defined municipalities that best show this recent transformation, beyond the establishment of key concepts for the understanding of this process and those responsible for such. In addition, there was a brief history of the presence of soy in Rio Grande do Sul, where the modernization of agriculture and the emergence of transgenic seeds had an important role in the advancement of this growing state. With this scenario a comparison is made between the advance of soybeans in northern and south of the state, by which it was established that the presence of farmers accustomed to large-scale production of wheat in the gaucho upland favored the deployment of cultivation before at the north than in the south. The Pampa, has long been conditioned to a number of factors that made it impossible to increase the soybean crop areas and only after the emergence and spread of Tillage System, this frame could be modified. From some theories some key players were selected to the understanding of what is happening in the Pampa region, and through interviews with producers and other actors, from selected municipalities, were found some search results as the identification of large numbers of producers coming other regions of the state and that purchases of machinery, implements and inputs are made in neighboring municipalities moving the economy centers already established in the service sector. However, this paper also outlines some trends for the soybean growing regions, for example, the search for the most profitable market niches, either by producing new varieties of grain or organic production.
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Obtenção e aplicação de padrões de isoflavonas de soja / Obtention and application of isoflavone standards from soybeansRibani, Marcelo 12 August 2018 (has links)
Orientadores: Carla Beatriz Grespan Bottoli, Carol Hollingworth Collins / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-12T11:07:55Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: O uso de padrões analíticos em análises cromatográficas é de fundamental importância para obter resultados analíticos confiáveis tanto em processos de validação de métodos quanto em análises rotineiras. Porém, o custo dos padrões de referência e sua disponibilidade para comercialização tornam o processo analítico muito caro e demorado. Neste trabalho foram obtidos padrões analíticos de isoflavonas de soja através da cromatografia líquida preparativa. Inicialmente foi desenvolvida uma método analítica por cromatografia líquida de alta eficiência, para separação e identificação de isoflavonas em extrato seco de soja. A seguir, foi realizada a transposição da escala analítica para a escala preparativa, iniciando pelo método da transposição direta. A caracterização e a pureza das isoflavonas obtidas foram verificadas a partir da pureza cromatográfica e pelos espectros na região do ultra violeta e visível, complementados pela espectrometria de massas e pela ressonância magnética nuclear. Os padrões obtidos por cromatografia preparativa apresentaram um teor de pureza de 93,1 % para daidzina, 99,8 % para daidzeína, 89,5 % para genisteína e 87,7 % para glicitina, permitindo, assim, o seu uso como padrões em análises rotineiras. Para demonstrar a aplicabilidade dos padrões obtidos, foi desenvolvido e validado um método para extração, hidrólise ácida e determinação das isoflavonas agliconas contidas em grãos de soja. Os resultados do conteúdo total de isoflavonas foram 283,5 ± 10,7 mg/100 g para soja não transgênica (BRS133) e 228,2 ± 13,8 mg/100 g para soja transgênica (BRS245RR), demonstrando diferenças significativas no conteúdo destas duas variedades de soja. / Abstract: The use of analytical standards in chromatographic analyses is very important to get trustworthy analytical results for validation of methodologies and for routine analyses. However, the cost of the available reference standards is high, prejudicing the overall analytical process. In this work, a transposition from analytical to preparative scale was carried out to obtain analytical standards of isoflavones from soybeans. An analytical methodology using high performance liquid chromatography (HPLC) was developed for separation and identification of isoflavones in dry soy extract. The transposition of the analytical parameters to the preparative scale was done initially through direct transposition. The characterization and purity of the isoflavones was determined by HPLC with spectra from a DAD detector, complemented by mass (MS+/-) and nuclear magnetic resonance spectrometries. The resulting isoflavone purities, after preparative separation and lyophilization, were 93.1 % for daidzin, 99.8 % for daidzein, 89.5 % for genistein and 87.7 % for glycitin, allowing their use as standards in routine analyses. To demonstrate the applicability of the standards obtained, an approach for extraction, acid hydrolysis and determination of the total amounts of isoflavone aglicones in soybeans was developed and validated. The results indicated total isoflavone contents of 283.5 ± 10.7 mg/100 g for non-transgenic (BRS133) and 228.2 ± 13.8 mg/100 g for transgenic (BRS245RR) soybeans, demonstrating significant differences in the isoflavone content of these two different soybeans. / Doutorado / Quimica Analitica / Doutor em Ciências
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Propriedades fisicas e funcionais de aglomerados a base de proteina de soja / Physical and functional properties of the clusters based on soy proteinColugnati, Patricia Girardi 26 August 2003 (has links)
Orientador: Flavia Maria Netto / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-03T16:41:15Z (GMT). No. of bitstreams: 1
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Previous issue date: 2003 / Resumo: O processo de aglomeração produz grânulos de estrutura porosa, que absorvem líquidos mais rapidamente, se dispersam e/ou dissolvem de forma instantânea, o que poderia favorecer as propriedades de hidratação das proteínas da soja. Tendo em vista o grande interesse atual nas propriedades nutricionais da soja, o desenvolvimento de um produto aglomerado oferecerá as vantagens de se ter proteínas de boa qualidade, aliadas à solubilidade e dispersibilidade, tão importantes no momento do consumo. O presente trabalho teve como objetivo estudar a influência dos diferentes isolados protéicos de soja comerciais (IPSs) nas propriedades físicas e funcionais de produtos aglomerados a base de proteína de soja. Cinco diferentes isolados protéicos de soja comerciais foram caracterizados quanto à composição química aproximada, hidrofobicidade superficial, conteúdo de grupos sulfidrilas livres, capacidade de absorção de água (CAA) e índice de dispersibilidade de proteína (IDP). O perfil de proteínas dos isolados protéicos foi analisado por eletroforese em gel de poliacrilamida na presença de dodecil sulfato de sódio (SDS-PAGE). Cada isolado protéico foi utilizado em duas formulações, formulação 1 composta por IPS (70%), maltodextrina (20%) e açúcar (10%) e formulação 2 composta por IPS (35%), soro de leite (35%), maltodextrina (20%) e açúcar (10%). As formulações foram submetidas ao processo de aglomeração úmida em instantaneizador piloto, utilizando-se os seguintes parâmetros: grelha de mesh redondo 1,5mm, temperatura de vapor 95° C e pressão de vapor 2 bar. Os produtos aglomerados obtidos foram analisados quanto à composição química aproximada, propriedades físicas (densidade aparente e de partículas, poros idade, distribuição granulométrica e microestrutura) e funcionais (índice de dispersibilidade de proteína, índice de separação, tempo de dissolução e dispersibilidade). Os isolados protéicos de soja apresentaram-se diferentes quanto às características estruturais e funcionais de suas proteínas, diferenças quanto à composição química aproximada, hidrofobicidade superficial, conteúdo de grupos sulfidrilas livres, capacidade de absorção de água, índice de dispersibilidade de proteína e tempo de dissolução, possivelmente devido aos diferentes processos de obtenção e isolamento, que levaram a diferentes graus de desnaturação. Os isolados LH, NB, MK e CH apresentaram proteínas com perfil eletroforético semelhante, com exceção do isolado SP, cujo perfil indicava hidrólise prévia de suas proteínas. Para ambas as formulações e independente do tipo de IPS utilizado, o processo de aglomeração resultou em produtos com estrutura porosa, bem definida e irregular, com partículas maiores do que os componentes utilizados em suas formulações e porosidade acima de 74%. Os aglomerados da formulação 2, no entanto, apresentaram grânulos mais estruturados e granulometria maior que os aglomerados da formulação 1. Em geral, os produtos com o mesmo IPS, obtidos a partir da formulação 2 apresentaram IDP menor e índice de separação maior do que os obtidos com a formulação 1, devido possivelmente, ao alto teor de lactose presente na formulação 2. Para os produtos obtidos com a formulação 1, o IDP e o índice de separação foram próximos aos do IPS utilizado, variando entre 13 e 84% para o IDP e de 4 a 67% para o índice de separação. As únicas exceções foram os aglomerados produzidos com o IPS SP, que apresentaram para as duas formulações estudadas, altos valores de índice de dispersibilidade de proteína e de índice de separação. O tempo de dispersão e a dispersibilidade dos aglomerados apresentaram valores próximos para todos os produtos, independendo da formulação ou do IPS utilizado, menos de 2 minutos e acima de 80%, respectivamente. O conjunto de propriedades estudadas permitiu concluir que, para a condição de processo estudada, independente das características dos isolados protéicos de soja utilizados ou formulações, a aglomeração resultou em produtos com as características necessárias para que um alimento em pó tenha boas propriedades de reidratação / Abstract: The agglomeration process produces porous granules which absorb liquids quicker and disperse or dissolve instantly, which could favor the hydration properties of soy proteins. Considering the current interest in the nutritional properties of the soybean, the development of an agglomerated product would offer the advantages of good quality protein allied to solubility and dispersibility, so important at the moment of consumption. The objective of this research was to study the influence of different commercial soy protein isolates (SPls) on the physical and functional properties of agglomerated soy protein based products. Five different commercial soy protein isolates were characterized with respect to their proximate chemical composition, surface hydrophobicity, free sulfhydryl group content, water absorption capacity (WAC) and protein dispersibility index (PDI). The protein profile of the protein isolates was analyzed using polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). Each protein isolate was used in two formulations, formula 1 composed of SPI (70%), malt dextrin (20%) and sugar (10%) and formula 2 consisted of SPI (35%), milk whey (35%), malt dextrin (20%) and sugar (10%). The formulations were submitted to a moist agglomeration process in a pilot scale instantanizer, using the following parameters: grid of 1.51J / Mestrado / Mestre em Alimentos e Nutrição
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EVALUATION OF TRIFLUDIMOXAZIN, A NEW PROTOPORPHYRINOGEN OXIDASE-INHIBITING HERBICIDE, FOR USE IN SOYBEANNicholas Robert Steppig (12474891) 29 April 2022 (has links)
<p> </p>
<p>In Midwestern soybean [<em>Glycine max </em>(L.) Merr.] systems, especially in Indiana, three summer annual weed species are among the most common and troublesome for soybean producers: tall waterhemp (<em>Amaranthus tuberculatus</em>), giant ragweed (<em>Ambrosia trifida</em>), and horseweed (<em>Conyza canadensis</em>). Evolved resistance to current herbicides [e.g. glyphosate and acetolactate synthase (ALS) ihibitors], coupled with a dearth of new herbicide active ingredients being commercialized in the last two decades, has made controlling these problematic weeds particularly challenging. Trifludimoxazin is a novel protoporphyrinogen oxidase (PPO)-inhibiting herbicide that is currently under development for use in soybean and is likely to be commercially applied either alone or in combination with the herbicide saflufenacil. Research herein was conducted to investigate foliar control of tall waterhemp (including genotypes that are resistant to applications of other PPO inhibitors), giant ragweed, and horseweed following applications of trifludimoxazin alone and in combination with other herbicides. Additionally, the efficacy of soil-residual applications of trifludimoxazin and trifludimoxazin plus saflufenacil was evaluated for tall waterhemp and compared to other preemergence herbicides commonly used in soybean. Finally, soybean response to preplant applications of trifludimoxazin and trifludimoxazin plus saflufenacil at various preplant timings was investigated along with impact of adding the WSSA Group 15 herbicides acetochlor, pyroxasulfone, and <em>S</em>-metolachlor to preemergence applications of trifludimoxazin plus saflufenacil.</p>
<p>Applications of 12.5 g ha-1 trifludimoxazin were highly efficacious in foliar applications on tall waterhemp (94% control) at 28 days after application (DAA), less effective when applied to giant ragweed (78% control, 21 DAA), and ineffective on horseweed (9% control, 28 DAA). When applied in combination with glufosinate, glyphosate, paraquat, or saflufenacil, foliar control for these species was 91% to 100%, except for trifludimoxazin plus glyphosate applied to a glyphosate-resistant population of horseweed (17%). Furthermore, foliar efficacy of trifludimoxazin applied to tall waterhemp or Palmer amaranth (<em>Amaranthus palmeri</em>) was not impacted by the presence of target-site mutations (ΔG210 or R128 in waterhemp, ΔG210 or V361A in Palmer amaranth) that confered resistance to saflufenacil and fomesafen.</p>
<p>Near complete soil residual control [≥ 98% at 2 weeks after application (WAA)] of tall waterhemp was initially observed with 12.5 to 50 g ha-1 of trifludimoxazin but were less effective (39% to 69%) relative to commercial standards of pyroxasulfone (91%) or sulfentrazone (95%) by 6 WAA. Combining saflufenacil at 25 or 50 g ha-1 with soil-residual applications of trifludimoxazin improved efficacy on tall waterhemp at 6 WAA relative to trifludimoxazin alone. With the exception of 12.5 + 25 g ha-1 (74%), applications of trifludimoxazin plus saflufenacil, respectively, resulted in comparable residual tall waterhemp control (84% to 92%) as the commercial standards. </p>
<p>Soybean injury following applications of trifludimoxazin was relatively low (< 10%), regardless of preplant application timing [0 to 28 days before planting (DBP)] or rate (6.25 to 25 g ha-1). However, the addition of saflufenacil increased soybean injury, especially when environmental conditions were more conducive to soybean response. For instance, at Pinney Purdue Agriculture Center (PPAC) in 2019 soybean injury 4 weeks after planting (WAP) was 28%, soybean population was reduced by 39%, and yield was reduced by 27% when trifludimoxazin plus saflufenacil was applied at 25 + 50 g ha-1. The experimental conditions that corresponded to this elevated soybean injury were coarse-texture soil, low temperatures, and high precipitation at the time of soybean emergence. Lower rates of this herbicide combination resulted in less injury, and soybean response was minimized (≤ 8%) when applications were made at least 14 DBP. The addition of Group 15 herbicides to applications of trifludimoxazin plus saflufenacil at planting did not impact soybean response, except for at PPAC in 2019, where the addition of acetochlor (51%) or pyroxasulfone (46%) to 25 + 50 g ha-1 was greater than without these Group 15 herbicides at 4 WAP (22%). Field research indicated soybean response to combinations of trifludimoxazin plus saflufenacil differed by cultivar in some instances, and greenhouse experiments determined the response was attributable to differential soybean cultivar sensitivity to the saflufenacil component of the mixture. </p>
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A CHARACTERIZATION OF SELECTION FOR EVOLVED RESISTANCE TO PROTOPORPHYRINOGEN OXIDASE (PPO)-INHIBITING HERBICIDES IN AMARANTHUS TUBERCULATUSWuerffel, Raymond Joseph 01 December 2014 (has links) (PDF)
Weed management options in agronomic crop production have been severely limited by widespread populations of weeds resistant to herbicides, including waterhemp [Amaranthus tuberculatus (Moq.) Sauer (syn. rudis)] resistant to foliar applications of herbicides that inhibit protoporphyrinogen oxidase (PPO; EC 1.3.3.4) activity (PPO-R). Herbicides within this site of action (WSSA site of action #14) remain efficacious when soil-applied to PPO-R waterhemp populations. Therefore, the continued use of these herbicides for soil-residual control of PPO-R waterhemp, especially in soybean production, is paramount with limited postemergence herbicides that remain effective. An improved understanding of the selection for PPO-R waterhemp would provide information to help minimize future loss of residual PPO-inhibiting herbicide activity. Five studies, consisting of 14 experiments, were conducted to improve our understanding of the selection for herbicide-resistant individuals. Soil-residual herbicides have been suspected to select for herbicide-resistant individuals; however, this phenomenon has never been observed experimentally in field conditions. This dissertation provides direct evidence from greenhouse and field experiments that significant selection pressure can occur from soil-residual herbicides; however, this selection for resistance could be delayed when using full commercial herbicide rates and effective herbicides from multiple sites of action. Also, the frequency of heterozygous individuals (RS) and PPO-inhibiting herbicide efficacy on RS individuals is a factor in the selection for herbicide resistance; however, current information on the these topics is limited. To provide additional information on RS individuals, a large-scale genotypic and phenotypic screen of multiple PPO-R waterhemp populations was conducted. It was determined that RS individuals were less frequent than expected and PPO-inhibiting herbicide efficacy on RS individuals was population-dependent. Finally, the hormetic effects of soil-residual herbicides have been paradoxically implicated as a means of both mitigating and exacerbating the selection for herbicide resistant biotypes; however, limited information was available on the hormetic effects of soil-residual PPO inhibitors. Greenhouse and growth chamber experiments were conducted to improve understanding of hormesis and soil-residual PPO-inhibiting herbicides. Experiments indicated that PPO-inhibiting herbicides may exert a limited hormetic effect on waterhemp germination below doses that cause a phytotoxic effect of the emerging seedling, indicating this effect may exacerbate the issue of selection for PPO-R waterhemp. Overall, data presented in this dissertation provides important information on the under-studied interaction between PPO-inhibiting herbicides and PPO-R waterhemp to safeguard the sustained efficacy of herbicides within this site of action.
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The effects of grazing cover crops on animal performance, soil characteristics, and subsequent soybean production in east-central MississippiBass, Bronson Scott 10 December 2021 (has links) (PDF)
Integrated crop-livestock systems (ICLS) incorporate cropping systems and livestock production by grazing cover crops. With a growing awareness in recent years regarding agricultural sustainability, these systems have begun to be re-introduced into the southeastern U.S. This study evaluated cover cropping systems under grazed no-till (GNT), un-grazed no-till (UNT), and un-grazed conventional tillage (UCT) management, in Mississippi. Beef cattle (Bos spp.) performance was significantly less in the cover crop treatment of oats (Avena sativa) + crimson clover (Trifolium incarnatum) + radish (Raphanus sativus; OCR) in both average daily gain (ADG; 3.03 lb hd-1 d-1) and total gain ac-1 (GAIN; 346 lb ac-1). Soybean (Glycine max) yield was unaffected by cover crop treatment and tillage. The lowest expected economic return was generated by OCR ($749.31 ac-1). Soil penetration resistance was unaffected by the influence of grazing. The greatest concentrations of soil organic carbon (1.44%) and soil nitrogen (0.20%) were observed in GNT.
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The effects of glyphosate salts and volatility-reducing agents (VRA) on dicamba volatilityGlenn, Nicole 09 December 2022 (has links) (PDF)
Dicamba is often tank mixed with glyphosate to increase herbicidal efficacy but may contribute to off-target movement (OTM). In recent years, volatilization has become problematic for dicamba-containing herbicides, resulting in increased regulatory requirements necessitating the use of volatility-reducing agents (VRA) for application. Research was conducted in 2021 and 2022 using low tunnels in a field environment and humidomes in a greenhouse environment to further assess how glyphosate salts and VRAs affect dicamba volatility. Our data indicate that the inclusion of glyphosate to dicamba can increase dicamba volatility, depending on the glyphosate salt used. The inclusion of the evaluated VRAs will decrease dicamba volatility when applied to a tank mixture of dicamba plus potassium salt of glyphosate.
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Conventional and strip-tillage systems with fertilizer placement in irrigated and dryland corn and soybean in the Mississippi DeltaHankins, James Chad 08 December 2023 (has links) (PDF)
Years of intensive tillage operations and heavy winter rainfalls have taken a toll on the soils in the Mississippi Delta causing compaction and nutrient losses due to runoff. The purpose of this research was to determine the effects of tillage systems and P and K fertilizer placement methods on corn and soybean production, as well as soil properties in the Mississippi Delta. The tillage treatments included conventional tillage, conventional tillage with subsoiling, and strip-tillage. The fertilizer placement treatments included a non-treated control, incorporated with tillage, and broadcast after tillage. Strip-tillage treatments reduced soil compaction and maintain nutrient levels while improving or maintaining yields in both crops. A more long term study is needed to determine if incorporating fertilizer with tillage will impact crop yields.
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