Effect of planting dates and varieties on seed yielding attributes of onion (Allium cepa Linn.) under west central table land zone of Odisha

Odisha produces about 419.09 thousand MT of onion from an area of 34.92 thousand hectares with a productivity of 120q/ha. Out of thirty districts, the major onion producing districts of Odisha are Kalahandi, Bolangir, Bargarh, Nuapada, Sambalpur, Ganjam, Angul, Deogarh and Boudh that comes under west central table land zone. Despite increase in areas, the productivity of onion is much lower due to limited availability of quality seeds in inadequate quantities suitable to locality and associated production technologies used, among the farmers. India needs around 9400 tons of onion seed annually for covering 14.30 lakh hectares area. Besides selection of suitable varieties, appropriate time of planting is also one of the important factors, which influences the growth, yield and quality of crop and thereby influencing seed yield. So, planting at different times is considered to test the suitable dates for quality seed production. Hence, the present investigation was taken up during the late kharif season of 2014-15 and 2015-16 in the experimental plot of College of Horticulture, Odisha University of Agriculture and Technology, Sambalpur, Odisha to find out suitable time of planting and varieties in split plot design for production of quality seeds with good seed yielding attributes. Onion planting on 25th September showed better performance with respect to seed yield attributing characters such as number of seed stalks per plant (3.05), length of scape (66.11 cm), diameter of scape (1.41 cm), diameter of umbel (5.35 cm), height of umbel (4.09 cm) etc. and was statistically superior to other treatments. The seed yield attributing characters helped to increase the total seed yield to 249.43 kg/ha at 25th September planting. Among the onion varieties Arka Niketan was significantly superior than other varieties tested and performed well with respect to seed yield attributing characters like, number of seed stalks per plant (3.18), diameter of umbel (4.59 cm), Days to seed maturity after bolting (61.17) etc. and gave the highest total seed yield of 214.7 kg/ha.