Methodology for the selection of soybean strains for germination, vigour and field emergence

Abstract

Soybean cultivars with seeds of higher physiological quality are of interest to farmers and seed companies. The aim of this study therefore, was to verify the genetic variability and the relationship that exists between various seed characteristics in order to identify tests that may be used in the laboratory when selecting soybean strains having seeds of greater germination, vigour and field performance. The seeds from 62 advanced strains of soybean were characterised as to first count and germination, classification of seedling vigour, electrical conductivity, accelerated ageing, seedling dry weight and seedling field emergence. Seed moisture content was determined before the tests for quality evaluation, and after the test for accelerated ageing. The experimental data were subjected to analysis of variance and covariance, estimating the phenotypic, genotypic and environmental correlations; heritability; coefficient of genetic variation; and gain from selection. The genetic variability of the characteristics under evaluation indicates that breeding can significantly contribute to an improvement in the physiological quality of soybean seeds. The tests of accelerated ageing, first count, germination and seedling dry weight can be used in selecting soybean strains with seeds of greater vigour and seedling field emergence. The estimated genetic gain for germination and seedling field emergence is 20% per selection cycle.