Features of formation of durability of corn hybrids seeds for their cultivation, postharvest processing and storage

The organization of the sowing material stocks is a necessary condition for stable seed production of any crop. Insurance, reserve, breeding and transi-tional funds are such stocks in corn seed production. Their creation and maintenance largely depend on the economic longevity of seeds, which can be formed at the stages of cultivation, harvesting, post-harvest processing and storage of seed. However, the data on the peculiarities of the formation of seed longevity of corn hybrids and their ability to long-term storage are lim-ited. That is why research in this area is considered relevant and important. The results of study of regularities of formation and factors of longevity of corn hybrids seeds of domestic selection are summarized in the executed work. Ecological, technical-technological and varietal factors are formed dur-ing corn cultivation, harvesting and processing. The greatest dependence is noted on the hydrothermal conditions, starting from the stage of cultivation, and then – in the stages after harvesting - the modes of drying and separation of seed. High economic durability is provided under the following conditions: hydro-term coefficient at the level of 0,5–0,7 – for vegetation and 0,3–0,4 – for maturing, drying temperature within 36–400С at humidity of seeds of 20–30%, fractional separation, removal from the seeds mass of the unstable frac-tion containing 18–20% of the total. Some of the factors included a sign of seed size, which is clearly manifested at the stage of long-term storage of seed. Sowing fractions differ significantly in terms of size, including the weight of 1000 seeds and their linear size. The greatest economic durability is inherent in the first and second of all factions. It is recommended to obtain them by calibrating the seeds on separating sieves with round holes with a diameter of 8–10 mm, depending on the hybrids. Prolonged storage is proposed on the basis of a combination of two factors – low humidity and airtight packaging of seeds. This significantly reduces resource costs and extends the economic longevity of corn hybrid seeds to 4–5 years.