Use of nonparametric selection indexes in studies of adaptability and stability of oat cultivars
Eduardo Alano Vieira, Fernando Irajá Félix de Carvalho, Antônio Costa de Oliveira, Giovani Benin, Claudir Lorencetti, Paulo Dejalma Zimmer, Elmar Luis Floss, Andreza Figueirola Martins, Luis Fernando Martins, and Marcos Fontoura de Carvalho
In Brazil, oat is cultivated over a vast area. There are, however, no reports on the use of the different traits of importance measured simultaneously in different environments for cultivar classification. The objective of our study was to compare nonparametric selection indexes for cultivar classification in their average performance in six environments, with and without fungicide application. The indexes used in the present study were classification sum index, modified classification sum index (using the standard deviation in the separation of means) and index of distance to the ideotype. Cultivar UPFA22 stood out with its classification as best genotype for all indexes. Moreover, the cultivar was well classified for grain yield and hectoliter weight. These indexes are efficient; the weights of the traits should however be modified according to the importance of the traits and/or an environmental stratification.