Resumo -O feijão-caupi é cultivado principalmente por agricultores familiares, com adoção de baixo nível tecnológico, onde o manejo de plantas daninhas é realizado com capinas, sendo cansativa e com baixo rendimento operacional. O objetivo deste trabalho foi avaliar a seletividade de herbicidas e a eficácia de controle de plantas daninhas na cultura do feijão-caupi, variedade BRS Guariba. O experimento foi conduzido à campo com aplicação dos herbicidas (g i.a. ha -1 ) sulfentrazone (500) e oxadiazon (600), em pré-emergência, e bentazon (600), bentazon + paraquat (39 + 62), fomesafen (225), fluazifop-p-butyl (250) e fomesafen + fluazifop-p-butyl (125 + 125), em pós-emegência, um tratamento com capina aos 20 e 35 dias após a emergência da cultura, e uma testemunha sem capina durante todo o ciclo da cultura. A aplicação do bentazon + paraquat provocou elevada fitotoxicidade no feijão-caupi, e o oxadiazon, sulfentrazone, bentazon e fluazifop-p-butyl garantiram de bom a excelente o controle das plantas daninhas, com produtividades semelhantes à obtida quando o controle foi realizado com duas capinas. O fomesafen associado ou não ao fluazifop-p-butyl provocou fitointoxicação moderada, atrasos no florescimento e colheita e redução de produtividade da cultura. A interferência de plantas daninhas durante todo o ciclo da cultura reduziu a produtividade de grãos em 42%. Palavras-chaves: Vigna unguiculata, planta daninha, controle químico, fitotoxicidadeAbstract -Cowpea is grown mainly by smallholders using low technological level, where weeds management is conducted by hoeing, a tiresome and low efficiency action. The aim of this study was to evaluate herbicide selectivity and weed control efficacy in cowpea, BRS Guariba cultivar. The experiment was conducted out with the application of herbicides (g a.e. ha -1 ) sulfentrazone (500) e oxadiazon (600), in pre emergence conditions, and bentazon (600), bentazon + paraquat (39 + 62), fomesafen (225), fluazifop-p-butyl (250) and fomesafen + fluazifop-p-butyl (125 + 125), in post emergence, one treatment with hoeing at 20 and 34 days after crop emergence and a check with weed interference during the whole crop cycle. Bentazon + paraquat application promoted high phytotoxicity in cowpea, and oxadiazon, sulfentrazone, bentazon and fluazifop-p-butyl guaranteed an excellent control of weeds, with yields similar to those obtained with two hoeing. Fomesafen associated or not to fluazifop-p-butyl caused moderate phytotoxicity, delays flowering and harvest, besides crop yield reduction. Weeds interference during the whole crop cycle reduced grain yield in 42%.

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The objective of this work was to use a partial diallel to evaluate the combining ability of 14 soybean genotypes and recommend superior combinations. Seven of the genotypes had high oil yield; other seven exhibited tolerance to sudden death syndrome and they generated 49 hybrids in a diallel cross without reciprocals. F 2 plants of each cross and the parents were evaluated for the following traits: number of days to maturity (NDM), oil content in the seeds (OC), grain yield (GY) and oil yield (OY). The results indicated the existence of genetic variability in the parents and progeny for all the traits. The rank of the parents based on the means was similar to the rank based on general

-The objective of this work was to evaluate corn cultivars grown in the state of Amazonas, Brazil, which simultaneously show high grain yield, adaptability, and stability. The trials were carried out in seven environments in the state of Amazonas, in a randomized complete block design, with two replicates. The grain yield of 30 corn cultivars was evaluated in four growing seasons, from 2011/2012 to 2014/2015. The genetic parameters were estimated by the REML/Blup methodology. The selection for adaptability and stability was based on the predicted genetic value and on the harmonic mean of the relative performance of the genetic values. Despite the existence of genotype x environment interaction, cultivars with high adaptability and stability were identified. Iranduba -lowland, in

-The purpose of this study was to investigate inbreeding depression (DE)

PALAVRAS-CHAVE Vigna unguiculata Interação genótipo × ambiente Produtividade KEYWORDS Vigna unguiculata Genotype × environment interaction RESUMO: O conhecimento da adaptabilidade e estabilidade de genótipos é fundamental, principalmente na fase de lançamentos de cultivares, pois visa reduzir os efeitos da interação genótipos × ambientes e facilitar a recomendação de cultivares. O objetivo foi selecionar genótipos de feijão-caupi de porte semiprostrado e semiereto para adaptabilidade e estabilidade produtiva cultivados em diferentes ambientes no Estado do Amazonas, utilizando os métodos baseados em regressão linear (Eberhart & Russell), na análise de variância (Annicchiarico) e em componentes principais (centroide). Os ensaios foram conduzidos em cinco ambientes do Estado do Amazonas sob o delineamento de blocos ao acaso com quatro repetições. Os efeitos de genótipos, ambientes e da interação genótipo × ambiente foram significativos. As metodologias utilizadas apresentaram de modo geral concordância nos resultados e permitem identificar entre os genótipos avaliados os de maior produtividade de grãos, estabilidade e adaptabilidade, considerando-se amplas condições ambientais. As linhagens MNC03-736F-6, MNC01-649F-2-1, MNC02-701F-2 e MNC01-649F-2-11 de porte semiprostrado, as linhagens MNC03-737F-5-9, MNC03-737F-5-10 e MNC02-675F-9-3 e a cultivar Tumucumaque de porte semiereto são as mais promissoras para o cultivo de feijão-caupi no Amazonas, pois aliam estabilidade e adaptabilidade à alta produtividade. ABSTRATCT: Knowledge of genotypes adaptability and stability of is essential, especially in cultivars launching phase since it aims to reduce the effects of genotype × environment interaction and facilitate the recommendation of cultivars. This work aimed to select genotypes of semi-prostrate and semi-erect cowpea, grown in different environments in the state of Amazonas, for adaptability and yield stability using methods based on linear regression (Eberhart and Russell), analysis of variance (Annicchiarico) and principal component (centroid). The tests were conducted in five environments of the State of Amazon under a completely randomized block design with four replications. The effects of genotypes, environments and genotype × environment interaction were significant. The used methodologies presented overall concordant results and allow the identification among the assessed genotypes, of those with highest grain yield, stability and adaptability, considering broad environmental conditions, and the MNC03-736F-6, MNC01-649F-2-1, MNC02-701F-2 and 2-11 MNC01-649F semi-prostrate strains, and the MNC03-737F-5-9, 5-10 and MNC03-737F-MNC02-675F strains 9-3 and the semi-erect cultivate Tumucumaque are the most promising for growing cowpea in the Amazon, as they combine stability and adaptability to high productivity. Seleção de genótipos de feijão-caupi para adaptabilidade e estabilidade produtiva no Estado do Amazonas Selection of cowpea genotypes for adaptability and stability in the State of Amazonas

RESUMORealizou-se, o presente trabalho, com o objetivo de avaliar a eficiência da seleção recorrente para a redução da estatura de plantas de mamona da cultivar Guarani (Ricinus communis L.), tornando-a com porte adequado para facilitar a colheita manual e/ou mecânica. Foram realizados quatro ciclos de seleção recorrente com a utilização de progênies autofecundadas na cultivar Guarani para redução da estatura das plantas, nas condições edafoclimáticas dos municípios de São Manuel -SP, Botucatu -SP e Penápolis -SP. As avaliações de estatura das plantas e de produtividade de grãos (kg.ha -1 ), dos quatro ciclos de seleção e do ciclo original foram realizadas nos municípios de São Manuel -SP, Botucatu -SP e Penápolis -SP na safra 2005/2006, sob um delineamento de blocos casualizados com cinco repetições e parcela útil de 30 m 2 . A análise de variância para as características avaliadas foi feita separadamente para cada local e conjuntamente para os três locais e, posteriormente, realizada a comparação das médias pelo teste de Tukey, a 5%. Foram estimados, para as três localidades, por análise de regressão, os ganhos genéticos dos quatros ciclos de seleção para estatura de plantas. A partir dos resultados obtidos pôde-se concluir que a seleção recorrente foi eficiente para a redução da estatura de plantas e que a cultivar de mamona Guarani apresenta variabilidade genética para essa característica e que a produtividade não foi influenciada pela redução da estatura de plantas. Termos para indexação:Mamona, variabilidade genética, ganho genético, produtividade, Ricinus communis. ABSTRACTThe aim of this work was to evaluate the recurrent selection efficiency for reduction of stature of the castor bean plants of the Guarani cultivar (Ricinus communis L.), turning it with appropriate strucuture to facilitate the manual and/or mechanic harvest. Four cycles of recurrent selection were accomplished through the utilization of self-pollinated progenies in the Guarani cultivar for reduction of plants stature, in edaphclimatic conditions of São Manuel-SP, Botucatu-SP and Penápolis-SP towns. The evaluations of plants stature and yield (kg.ha -1 ) of the four selection cycles and the original cycle (cycle 0) were accomplished in São Manuel-SP, Botucatu-SP and Penápolis-SP, under a randomized block design with five repetitions and useful parcels of 30 m 2 . The analysis of variance for the characteristics plant stature and yield was made apart to each environment and together for the three environment and, afterwards one performed the average comparison by the Tukey test using 5% of probability. One estimated for the three environments, by the regression analysis, the genetic gains of the four selection cycles for plant stature. One concluded that the recurrent selection was efficient to the reduction of plant stature and that Guarani castor bean cultivar could create genetic variability for this characteristic and the yield was not influenced by the reduction of plants stature.

Weeds negatively affect cowpea plants, causing reduced growth, delayed development and yield loss. The aim of this study was to assay selectivity and effectiveness of weed control herbicides in cowpea cropping field conditions. For selectivity evaluation, the herbicide S-metolachlor, was used pre-emergence (PRE), and carfentrazone-ethyl, clethodim, fenoxaprop-p-ethyl, fluazifop-p-butyl and quizalofop-p-ethyl post-emergence (POST). In effectiveness evaluation, S-metolachlor (PRE), and carfentrazone-ethyl (POST), S-metolachlor in PRE and fluazifop-p-butyl (POST), clethodim, carfentrazone-ethyl and clethodim, fenoxapropp- ethyl, carfentrazone-ethyl and fenoxaprop-p-ethyl, fluazifop-p-butyl, carfentrazone-ethyl and fluazifop-pbutyl, quizalofop-p-ethyl and carfentrazone-ethyl and quizalofop-p-ethyl (POST). Two controls were included, one with weeding at 15 and 35 days after sowing (DAS) and the other without weed control. Carfentrazone-ethyl caused mild phytotoxicity in plants seven days after application, but did not reduce yield (2337 kg ha-1). The levels of weed control and productivity obtained with S-metolachlor alone or in association with carfentrazoneethyl or fluazifop-p-butyl, associated or not with carfentrazone-ethyl, were similar to those obtained with weeds. Spraying with carfentrazone-ethyl alone resulted in low control effectiveness and reduced yield (1511 kg ha-1). Weed interference during the crop cycle reduced yield by 77% (531 kg ha-1). The selectivity and effectiveness obtained with the herbicides should be considered as an agronomic and economically-viable.