Onion - Small Onion (Aggregatum); botanically called Allium cepa var. aggregatum; Belongs to the family
Alliaceae
Varieties: CO 1, CO 2, CO 3, CO 4 and MDU 1, CO(On) 5 free flowering and seed setting type.
Soil: Red loam to black soils with good drainage facilities. It grows well between pH range of 6-7 and a mild season in without extremes of heat and cold.
Season and sowing: Sow the medium sized bulbs during April – May and October – November.
Seed rate: 1000 kg/ha.
Preparation of field: Plough the land to a fine tilth. Form ridges and furrows at 45 cm spacing.
Sow the bulbs on both the sides of the ridges at 10 cm apart.
Irrigation: After sprouting, irrigate at weekly intervals. Withhold irrigation 10 days before harvest.
Application of fertilizers: Apply FYM 25 t/ha, Azospirillum 2 kg and Phosphobacteria 2 kg/ha, N 30 kg, P 60 kg and K 30 kg/ha as basal and 30 kg N/ha on 30th day of sowing.
Plant protection against Pests
Thrips and onion fly: Methyl demeton 25 EC 1 ml/lit or dimethoate 30 EC 1 ml/lit or
monocrotophos 36 WSC 1 ml/lit with Teepol 0.5 ml/lit.
Cutworm: Drench the soil with chlorpyriphos @ 2 ml/lit.
Protection against Diseases
Leaf spot: Spray Mancozeb 2 gm/lit or Copper oxychloride 2.5 gm/lit. Add Teepol 0.5 ml/lit of spray fluid.
Harvest and Yield
12 – 16 t/ha in 70 to 90 days. 18 t/ha in 90 days for CO(On) 5 onion
Clean and dry the bulbs for 4 days in shade soon after harvest.
Spray Maleic hydrazide at 2500 ppm 15 days before harvest to extend the shelf life of onion.
