Genetic effects on seed quality in diallel crosses of popcorn

Abstract

The failure to obtain the ideal stand is one of the causes of decreased crop yields, in this sense it is important to investigate the genetic effects related to seed quality. The aim of this study was to measure the general combining ability (GCA), the specific combining ability (SCA) and the reciprocal effects (RE) for popcorn seed quality in addition to evaluate the association between germination and vigor tests with field emergencein order to identify hybrids with better germination and vigour. Ten inbred lines were evaluated using a complete diallel cross with reciprocals. Seed quality was measured by germination tests (GT) and by modified cold vigour tests (MCV). In the GT, the numbers of strong normal seedlings (SNS), weak normal (WNS), abnormal (AS) and ungerminated seeds (UGS) were counted. In the MCV, the numbers of normal seedlings (NPC), abnormal (ASC) and ungerminated seeds (UGSC) were counted, and the plants' dry matter (DM) was measured. Analysis of variance for GCA, SCA and RE were significant for all variables. The quadratic components for SCA were higher than those for GCA for the SNS, AS, UGS, ASC and UGSC traits, which indicates higher significance for the non-additive effects. The most favourable GCA estimates, were found in lines P3 and L70. The best hybrids were P1xL70, P3xP6 and P8xL70. The RE results showed that L70 and P3 should be used as the female parent in the P1xL70 and P3xP6 hybrid crosses, respectively. The MCV was the test that was most strongly correlated with field emergence, with a magnitude of 0.667.