Effects of planting density and diameter of mother bulbs on onion seeds yield

Abstract

A field experiment was set up in central Banat, the village of Aleksandrovo, in the period 2017/2018. year. The influence of planting density and size of planted bulb (excerpt) on the production of onion seeds of the variety „Dutch yellow“ (Stuttgarter Reisen) was investigated, using four fractions of onions with a diameter: 3-4; 5-6; 7-8 and 8-9 cm. They were planted in densities of 98,000 to 168,000 plants/ha (A), 140,000-196,000 plants/ha (B) and 280,000-350,000 plants/ha (C). The harvest of flower stalk (seeds) was carried out on July 23, when certain measurements were performed, of which we single out here: the number of flowering stalks per bulb and hectars, the number of fruits in inflorescence, the number of seeds in inflorescence and seed yield per hectare (kg). Larger bulbs in all densities had a larger number of formed flower stalks (bulls), and their number ranged from 1.53 to 3.10. Contrary to this parameter was the number of fruits in the flower stalks. Accordingly, the highest seed yield was achieved in the densest crops (1.615 kg ha-1 и 1.591 kg ha-1) by using medium-sized bulbs that were 3-4 and 5-6 cm in diameter. Dense planting of mother bulbs reduces the lodging of plants, and the competition caused by that density leads plants for onion seed production to focus their energy on the growth of generative organs, not leaves.