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Resumo:O objetivo deste trabalho foi avaliar a resistência de genótipos de feijoeiro aos principais patógenos da cultura, bem como a adaptabilidade e a estabilidade de produção de grãos desses genótipos. Avaliaram-se 26 genótipos de feijoeiro quanto à resistência a Colletotrichum lindemuthianum, Fusarium oxysporum f. sp. phaseolie Xanthomonas axonopodis pv. phaseoli, por meio de inoculação, em laboratório, e em 19 ensaios de valor de cultivo e uso (VCU), em diferentes locais do Estado de São Paulo, nas safras das "águas", "seca" e "inverno", durante os anos agrícolas 2011, 2012 e 2013. Dezoito genótipos foram considerados resistentes: sete deles a C. lindemuthianum, sete a F. oxysporumf. sp. phaseolie quatro a X. axonopodispv. phaseoli. A reação de resistência aos patógenos está associada à estabilidade dos genótipos. Por meio das análises GGE biplot, foi possível identificar genótipos com adaptabilidade e estabilidade superiores às das testemunhas, nos dois grupos de tegumento avaliados, em todas as épocas de semeadura.

Common bean (Phaseolus vulgaris L.) is frequently grown in weathered soils with low phosphorus (P) availability, and this is one of the main limitations on its production. This study aimed to assess 20 common bean genotypes in a hydroponic system to select the best P concentration for inducing nutritional deficiency and to classify the genotypes in terms of nutrient utilization efficiency. The concentrations of P applied were 8.00, 4.00, 2.00 and 0.05 mg L¹. At 21 days, in the plot subjected to an application of the most severe stress, the 0.05 mg L¹ dose of P, had smaller plant size and early leaf abscission was observed. The 4.00 mg L¹ dose of P was the most efficient in inducing stress for discrimination of cultivars in terms of efficiency of use of P. The following genotypes: IAPAR 81, Carioca Comum, IAC Carioca Tybatã, IAC Imperador and G 2333 stood out as being efficient and responsive to P, while the two cultivars DOR 364 and Jalo Precoce were the most inefficient and unresponsive.

Anthracnose caused by the fungus Colletotrichum lindemuthianum is one of the main diseases affecting the common bean (Phaseolus vulgaris L.), and the pathogen is characterized by wide variability, with more than 50 physiological races identified in Brazil. Greater occurrences of races 65, 73, and 81 have been observed in Brazil along with the occurrence of pathogenic variability among isolates of a single race, destabilizing the resistance of commercial cultivars. Therefore, the aim of this study was to identify physiological races of C. lindemuthianum isolates collected in the states of São Paulo and Santa Catarina, Brazil and to test for variability among the isolates of race 65. The classification of 51 isolates resulted in the identification of 10 different physiological races: 4, 38, 55, 65, 73, 81, 83, 85, 321, and 351. Races 65 and 81 predominated, with frequencies of 37.25 and 35.29%, respectively. Regarding the isolates of race 65, wide physiological variability was evident, suggesting that a new differential set should be applied to detect the levels of variation among isolates of a single race of the pathogen.

Com o advento da agricultura moderna, as sementes crioulas foram, em geral, substituídas por cultivares híbridos, com elevado potencial produtivo, porém mais dependentes de insumos e tecnologias intensivas. O objetivo deste trabalho foi avaliar variedades de milhocrioulo, de forma a identificar materiais mais produtivos e que propiciem o processo sustentável no qual os próprios grãos possam ser utilizados como semente. Foram avaliadas 15 variedades de milho crioulo, tendo como testemunhas as cultivares comerciais BR 106 e IPR 114. Os experimentos foram conduzidos em Arapongas e Imbaú, Estado do Paraná, durante o ano agrícola de 2004/2005, sem a utilização de insumos externos. O delineamento utilizado foi o de blocos casualizados com quatro repetições. As parcelas foram constituídas por duas linhas de 4 m, espaçadas 90 cm entre linhas e com 20 plantas/linha. As variedades crioulas P-13, P-15 e P-05 demonstraram potencial produtivo elevado em sistemas de baixo nível tecnológico, dentro de cada local, assim como na média dos locais. As variedades P-19 e P-10 têm sua recomendação restrita à localidade de Imbaú, enquanto que P-16 e P-17 serão direcionadas para a localidade deArapongas. With the advent of modern agriculture, landrace seeds were replaced by hybrid cultivars, which feature high grain yield potential – though more dependent on intensive technologies. The objective of this work was to evaluate maize landraces, in order to identify more productive materials that can lead a sustainable process in which the grains themselves in which can be used as seed. Fifteen maize varieties were evaluated, with commercial cultivars BR 106 and IPR 114 as controls. The experiments were carried out in Arapongas and Imbaú (Paraná State), during the 2004/2005 agricultural year, withoutexternal input. The design used was randomized blocks with four replications. The plots were two 4-m rows, spaced 90 cm apart, with 20 plants/row. The landrace varieties P-13, P-15 and P-05 showed high productive potential in low technological level systems, at eachlocation, as well as in the average of both locales. The varieties P-19 and P-10 have their recommendation restricted to Imbaú, while P-16 and P-17 will be indicated for Arapongas.

Com o advento da agricultura moderna, as sementes crioulas foram, em geral, substituídas por cultivares híbridos, com elevado potencial produtivo, porém mais dependentes de insumos e tecnologias intensivas. O objetivo deste trabalho foi avaliar variedades de milho crioulo, de forma a identificar materiais mais produtivos e que propiciem o processo sustentável no qual os próprios grãos possam ser utilizados como semente. Foram avaliadas 15 variedades de milho crioulo, tendo como testemunhas as cultivares comerciais BR 106 e IPR 114. Os experimentos foram conduzidos em Arapongas e Imbaú, Estado do Paraná, durante o ano agrícola de 2004/2005, sem a utilização de insumos externos. O delineamento utilizado foi o de blocos casualizados com quatro repetições. As parcelas foram constituídas por duas linhas de 4 m, espaçadas 90 cm entre linhas e com 20 plantas/linha. As variedades crioulas P-13, P-15 e P-05 demonstraram potencial produtivo elevado em sistemas de baixo nível tecnológico, dentro de cada local, assim como na média dos locais. As variedades P-19 e P-10 têm sua recomendação restrita à localidade de Imbaú, enquanto que P-16 e P-17 serão direcionadas para a localidade de Arapongas.

ABSTRACT Given the impact of climate issues and their direct influence on agricultural production, the aim of this study was to identify superior genotypes of dry edible common bean under water deficit. Thus, 30 common bean genotypes were evaluated under controlled greenhouse conditions in a randomized block experimental design with split plots and four replications; the plots consisted of the water treatments (irrigated and water deficit) and the split plots consisted of the genotypes. The results showed genetic variability among the accessions evaluated, and in spite of significant reduction in grain yield and stomatal conductance under water deficit, these two traits showed significant, positive correlation and are able to be applied in early selection of genotypes under this stress condition. Another important response was in relation to the genotypes SER-16, SEN 92, FT Paulistinha, Carioca Precoce, IAC Imperador, and SXB 410, which showed the best yield performances in the two water treatments applied. They can be widely used in breeding programs for development of new cultivars, especially aiming at drought tolerance.

ABSTRACT: The aim of this study was to investigate the effect of heat stress on 12 bean genotypes through the analysis of their reproductive biology in terms of flowering, pollen viability, meiotic behavior, and production. Plants were grown in a climate chamber at 25-20 °C (day and night) and at a high temperature treatment 37-26 °C (day and night) from the vegetative (V4) development stage to physiological maturity. The experimental design was 2 × 12 factorial arrangement with six replications and the factors consisted of heat treatments and genotypes. In three replications, the number of newly opened flowers was checked daily. At physiological maturity, the following traits were evaluated: percentage of pod set, number of pods, number of viable seeds, number of aborted seeds, 100 seed weight, and seed yield (g per plant). The other three replications were used to collect flowers to create slides to study viability of the pollen grain and analyze the meiotic behavior. The heat treatment factor significantly affected the following traits: total number of pollen grains, number of flowers, number of pods, pod set, number of viable seeds, 100 seed weight, and seed yield. The raised temperature reduced these variables, except for percentage of pod set, and increased meiotic irregularities. The mean values regarding seed yield were 16.39 g per plant for the control treatment and 7.46 g per plant under high temperature. IAC Imperador, FT Nobre, Pérola, BRS Estilo, and IAC Diplomata stood out for higher bean seed yield under increased temperature.