Chemical quality parameters of maize hybrids in various FAO maturity groups as correlated with yield and yield components

Abstract

An experiment was set up at five locations in Hungary in 2005, in a randomised block design with four replications. At each location 24 hybrids were tested from each of four maturity groups (FAO 200, FAO 300, FAO 400, FAO 500). Evaluations were made of the yield average (t/ha) and the yield components of the sample ears: ear length, number of kernel rows, thousand-kernel mass and kernel/cob ratio. This was followed by chemical analysis to determine the protein, oil and starch contents of the kernels. The chemical quality parameters were recorded for almost 100 hybrids, and the correlations of the protein, oil and starch contents with yield and yield components were analysed. It was found that in all the maturity groups the yield was closely correlated with the thousand-kernel mass (0.72). In each maturity group the highest yield averages were associated with the greatest average starch contents, except for the FAO 500 group in the Szarvas location, where the development of secondary ears contributed to the achievement of the highest yield average. A very close correlation was found between the starch content and the thousand kernel mass (0.91). The variety caused greater differences in protein content than the location. This was also true for the oil content in the FAO 200 and FAO 400 groups, but only in the FAO 400 group in the case of starch content. More starch was incorporated at wetter locations, where the protein content of the samples was lower.