Heat resistance of seeds of corn hybrids and features of their drying

Abstract

Goal. To determine the indicators characterizing the heat resistance of seeds of corn hybrids, establish optimal methods of drying them while maintaining high germination. Methods. The research was conducted during 2022–2024, using the following methods: laboratory — to determine the chemical composition of the grain and the degree of its thermal damage, as well as the similarity depending on the modes of thermal drying; model — to dry seeds of different humidity in different ways; mathematical and statistical — to assess the reliability of the data obtained. Results. It was determined that the most accurate heat resistance of corn seeds during drying could be established by the indices of the content and ratio of protein fractions, thermal fracturing, and germination of grains. The decrease in heat resistance and similarity was accompanied by a decrease in the content of protein fraction — albumins, an increase in the amount of insoluble residue, as well as the appearance of grains with thermal damage (internal fracturing). Such changes occurred when the seeds were heated to a temperature of 45–50°C, and depended on their humidity, as well as on the rate of moisture evaporation, which usually exceeded 0.4% per hour. Conclusions. To obtain seeds with high germination, it is recommended to dry them using a temperature regime that ensures the preservation of the content of water-soluble proteins — albumins, and the integrity of the grain. The drying parameters of corn heads should be controlled by the heating temperature of the grain and the rate of loss of humidity. Seed germination as an indicator of heat resistance is recommended to be determined by cold germination (cold test), which quite accurately characterizes the viability and dependence on the drying process.