THE EFFECT OF HYPERTHERMIC STRESS ON GERMINATION, SEEDLING GROWTH, ASCORBIC ACID CONTENT AND ASCORBATE PEROXIDASE ACTIVITY IN MAIZE (Zea mays L) HYBRIDS

Abstract

The hyperthermic shock (HTS) of +50 °C for 30 min applied to the seeds of maize hybrids with different toleran- ces to high temperatures and cold caused a reduction in the germination percentage in all hybrids, the highest level of reduction in seed germination and morphological parameters being observed in the high temperature sensitive hybrid (P. 427). However, in the high temperature resistant hybrid (P. 374) HTS insignificantly affected the growth of roots and shoots, but significantly decreased the accumulation of root biomass. The results obtained show that a high endogenous ascorbic acid (AcA) content is an important factor in maize tolerance to HTS during the juvenile phase. In P. 427 seedlings, HTS caused a decrease in the AcA content in both roots and shoots. This phenomenon may be associated with the consumption of AcA to protect cells from oxidative stress-induced damage in maize seedlings. Keywords: maize seeds, hyperthermic shock, germination, seedling growth, ascorbic acid, ascorbate peroxidase. DOI: https://doi.org/10.59295/sum1(191)2026_25