Rate of moisture-lossing of maize grain during maturation for hybrids which belong to different maturity groups

Abstract

Moisture-lossing of grain for hybrids’ bred in Kharkov which belong to different maturity groups were examined by the authors.

The distinctive amplitude of phenotypic values for grain moisture of hybrids from different maturity groups in the process of maturation has been shown. The highest absolute stable value of this indicator were registered in the group of middle-ripe maturity hybrids.

Range of variability of grain moisture for hybrids middle-early and medium-late maturity groups gradually decreased from 30 to 40 days after pollination, and since 45th day began to rise again, it is may depend from manifestation of inter-genotypes differentiation.

It were established that appearance of physiological ripeness is a reliable criterion for the dividing of grain moisture-lossing period of two commonly different stages.

In our study the physiological ripeness were observed when the grain moisture reached 30-34%.

The authors have shown that during the first ("physiological") stage, the rate of moisture-loss were high for the group of middle-early hybrids – 1.27 % and 1.68 % per day in 2012 and 2013 respectively. But for middle-ripe hybrids moisture-loss – 1.13 and 1.62 % per day, and for the medium-late maturity group – 1.09 and 1.05 % per day in 2012 and 2013, respectively.

It were noted in the article that increase indexes of repeatability for grain moisture data during maturation (from 0.21 to 0.37) were started since 40 days after pollination. It is indicates an increase of the influence of "genotype - environment" at the level of phenotypic expression of the trait.

When considering the rate of moisture-lossing it were observed the same pattern (from 0.05 to 0.44). Thus, the authors have been allocated 5 hybrids consistently better than the standards by the level of harvest, grain moisture. It were made on the background of the establishment of common group patterns when ripe grain moisture-lossing caused by different rates of this process and the presence of distinct genotypic differences mediated influence of the environment.