Optimization of High Density Planting with Drip Irrigation in Rabi Onion

Irrigation scheduling is necessary for increasing onion production in an Agro-climatic zone III A and B of Bihar, where water is becoming scarce gradually and a limiting factor for onion production. Field experiments were conducted during the Rabi season of 2013-14 and 2014-15 at the experimental farm, Nalanda College of Horticulture, Noorsarai, Nalanda. The objectives were to standardize high density planting with drip irrigation and to study the yield performance and storability on onion in Nalanda region. The treatments consisted of factorial combination of three irrigation intervals (2, 4 and 6 days) and four population densities (2000000, 1333333, 1000000 and 666666 plants/ha) corresponding to 10 x 5, 10 x 7.5, 10 x 10 and 15 x 10 cm respectively. The experiments were laid out in randomized block design replicated three times. Results revealed that the highest marketable yield was significantly favoured by 2 days interval followed by 4 days. However, lower plant spacing 10 x 5 cm recorded higher plant height, minimum maturity days, grass and marketable bulb yield were significantly higher with plant spacing 10 x10 cm followed by 15 x10 cm. The marketable bulb yield was significantly higher with interaction of T7 (10 x10 cm with 2 days irrigation interval) 1000000 plant density and 2 days irrigation interval than other treatment combinations. From the results of the study, it can be concluded that 2 days interval irrigation with a plant density of 1000000 (10x10 cm) plants per hectare can be practised for maximum onion bulb yield.