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Common bean is one of the most important legumes in Latin America, mostly grown in soils with low phosphorus (P) availability. Thus, this study aimed to evaluate the responses of 20 bean genotypes to P deficiency. The experiment was a completely randomized design in a 2 ? 20 factorial arrangement; the first factor consisted of P levels and the second factor, of 20 bean genotypes, with six replications. The substrate was a Red Eutrophic Oxisol with low P content. For application of the P treatments, it was applied simple superphosphate, consisting of two levels: restrictive and control, with the application of 45 and 90 kg·ha-1 of P2O5, respectively. At 28 days, we observed the first symptoms of nutrient deficiency, with the decrease in the relative chlorophyll index in the restrictive level treatment. In addition, the treatments were effective in differentiating effects of both factors levels of P and genotypes for most traits evaluated relative to shoot, root and grain yield. It was possible to classify the genotypes in relation to use efficiency and responsiveness to P application, according to their average yield performances. Seven genotypes presented better performances for both P levels, being classified as Efficient and Responsive: G 2333, IAC Carioca Tybatã, IAPAR 81, IAC Imperador, IAC Formoso, BRS Esplendor and IPR Tangará; the first four genotypes were also classified as Efficient and Responsive under hydroponic conditions. [ABSTRACT FROM AUTHOR]

Two experiments with 25 maize commercial hybrids were carried out in a direct sowing system in Southern Brazil in the harvests of 2009/2010 and 2010/2011. Quantitative descriptors were used with the objective of determining the genetic divergence and the relative contributions of traits among hybrids for extraction of inbred lines. This study was carried out in Oxisol soil using a randomized block design with four replicates. Data were subjected to combined analysis of variance, and based on the multivariate analyses, Tocher and average linkage (UPGMA) cluster analyses, based on generalized distance of Mahalanobis, to quantify divergence in addition to Singh criterion to validate trait with the most contribution. The multivariate methods were consistent with each other, and the weight of 100 grains was the trait that contributed most to the divergence and had similar behavior in grain yield between hybrids in both years. Furthermore, this descriptor representing significant genetic variability for crossings and lines extraction to hybridization between BM 3061, ATL 200 and P 30B39 Y. [ABSTRACT FROM AUTHOR]

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Copyright of Bragantia is the property of Instituto Agronomico de Campinas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bragantia is the property of Instituto Agronomico de Campinas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)