Influence ofmother onion planting time on the yield and sowing its qualities onion seeds

Relevance. In Uzbekistan, especially in the south of the republic, in recent years, early ripe varieties of onion Sumbula, Ravnak, Bakhora have become widespread. However, the technology of seed production of early maturing varieties has not been developed. In this regard, several studies were carried out to identify the optimal time for planting the mother plants of the early maturing onion variety Sumbula by using the favorable climatic conditions of southern Uzbekistan.Material and methodology. The material for the research was the early ripe onion variety Sumbula, bred by the Research Institute of Vegetable and Melon Crops and Potatoes. The studies were carried out according to the Methodological guidelines for the ecological testing of vegetable crops in the open field etc. The dates of seed planting were studied.Results. Studies have shown that the highest seed yield (0.97 t/ha) was obtained in the early autumn planting of mother plants on September 1. It was 20% more than in the control variant – September 15. At later planting dates, the seed yield decreases sharply.When mother plants were planted on October 30, the seed yield was only 0,46 t/ha, or 59.7% of the control.The yield of onion seeds increases, mainly due to the more powerful development of plants during early autumn planting – the formation of large leaves, inflorescences, and additional arrows. The more large and powerful leaves, the more plants have the ability to synthesize plastic substances in the process of photosynthesis and accumulate a high yield.