Inheritance of Grain Dry-Down in Corn (Zea mays L.).

Abstract

Breeding for faster grain dry-down in corn is an essential objective of modern corn breeding programs all over the world due to important economic reasons. A reliable, large scale, fast, non-destructive wood moisture Voltcraft FM-200 Humidity meter was used to successively measure the grain moisture of field corn individual plants for a large number of corn genotypes, hybrids and inbred lines, in different stages of Pioneer corn breeding program, during 2010-2012. A calibration curve (successive determinations of the grain moisture by using in parallel the wood moisture meter readings and grain moisture obtained by standard gravimetric method) has been used to transform the wood moisture meter readings in estimated % grain moisture (EPGM). DDIND values, a propose selection index, computed as the slope between EPGM and measurement timing, have been used to apply ANOVA analysis; Preliminary results showed that the methods allowed identification of real genotypic differences and advance genotypes with fast DDR. Using the components of variances obtained in ANOVA analysis, an estimate of the heritability of the DDIND was computed. The relative large value of the heritability, of more than 0.50 (50%), suggested the efficiency of the method in detecting genotypic variations and that selecting by using DDIND for rapid dry down would result in an efficient improvement of this important agronomic trait of modern corn inbred lines and hybrids.