The sum of temperature units in different pheno-phases of development of seed maize regarding the production year

Abstract

The aim of this study was to determine variability of temperature sums for the occurrence of pheno-phases of silking, tasselling and pollination of seed maize. Nine maize inbred lines were tested in two production years. Compatibility and overlapping of silking, tasselling and pollination of parental components in a seed crop are important for achieving high yields. According to obtained data, the degree of accumulation of temperature sums was higher in the first year than in the second production year for all stages, except for the beginning of tasselling. The differences were statistically significant: the greatest and smallest differences were obtained for tasselling (t2 - 70.9oC) and the beginning of silking (s1- 20.86oC), respectively. The effect of genotypes on differences in temperature sums was the greatest for all pheno-phases, p<0.005. The effect of the production year on the number of temperature units necessary for silking and pollination was also high, but there was no high statistical effect on the beginning of tasselling. Since maize is a plant species that is grown in different regions, maize growing practices should be adjusted to the main aim of maize production, to achieving high and stable yields.