Effects of row spacing and seed rate on onion quality and set yield

Abstract

The effect of sowing schemes and seed rates on onion sets yield and quality was investigated in 1999 – 2000 at the Lithuanian Institute of Horticulture. Seeds were sown according two schemes: (8 + 15) X 4 + 63 and (8 + 27) X 3 + 61. In each of them seed rates were 14; 17; 20; 23; 26 mlnha.
The highest yield of standard onion sets (14.65 t/ha) was obtained at the scheme (8-15) X 4-63 and at 20mln/ha seed rate. When sowing according to this scheme and the rate of seeds being 20 mlnha. When sowing according to the scheme (8 – 27) X 3 – 61 the highest yield of standard onion sets – 13.13 tha was obtained when applying the seed rate of 17 mlnha.
When increasing the seed rate according to the scheme (8+15) X 4 + 63 over 20 mlnha, and according to the scheme (8 – 27) X 3 – 61 over 17 mlnha the yield of standard onion sets was decreasing and sets reached maturity later. At lower seed rates the amount of standard sets was decreasing as well because in thinner crops the amount of bigger sets was higher than of standard ones.
Key words: sowing scheme, seed rate, onion sets, onion bulbs, standard yield.