The effect of seed moisture content of hybrid maize at harvest time on seed germination traits and antioxidant enzymes activity under simulated conditions of some environmental stresses

Abstract

Abstract Seed quality of hybrid maize is affected by many factors, including maturity time and environmental conditions. In this study, the effect of four maturity times of hybridized maize from male and female plants was investigated in terms of grain moisture content (30, 35, 40 and 45%) in 2021 & 2022 in Kermanshah, Iran. The experiments were on maize seed vigor using the standard germination and simulated tests of cold, Hiltner brick gravel and germination test under drought stress conditions. The results showed that highest percentage and rate of germination were obtained from the treatment with 30% moisture content at maturity (99% and 0.037 germination per hour). Brick gravel and drought stress tests reduced germination percentage compared to the standard test. Based on Guasnr model, the nonlinear model of germination response curve was fitting to the percentage of moisture contents at maturity time for various tests. In general, due to the reduction in the slope of germination response curve at high moisture content at maturity time for different tests, 30 and 35% moisture content at maturity time were found to be appropriate to produce high quality maize seeds. The early harvest, or in other terms 45% moisture content of the seed at the time of harvest, resulted in enhanced activities of Catalase, Ascorbate peroxidase and Malone Dialdehyde enzymes in different tests. On the other hand, the maximum activities of the Antioxidant enzymes were found in the germination test under drought stress conditions in the amount of 36.6 µmolmin− 1mgprotein Catalase and 2829 nmolmin− 1mg Ascorbate peroxidase.