Cultivation of Onion for Seed Purpose
Onion bulbs are produced from seed while onion seed is produced from bulbs. Generally seed production of onion is taken in rabi season.
Preparation of Land for Seed Purpose:
1. Land is ploughed 2 to 3 times in crosswise manner.
2. Clods are crushed with the help of harrow or maind.
3. 25 to 30 tons of FYM/ha. is well mixed in soil during harrowings.
4. 2 to 3 harrowings are done to brought the soil to fine tilth.
Planting Method:
1. Onion bulbs are used as seed material.
2. The optimum time for sowing is October as seed production is done only in rabi season.
3. About 1200 to 1300 kg bulbs are required for planting in one hectare.
4. Ridges are opened at 60 to 75 cm distance and bulbs are planted on one side of the ridge half way above the bottom.
5. At each spot one bulb is planted at 15 to 20 cm apart for each other.
6. The bulbs are planted either before or after the irrigation.
Seedrate:
Seedrate of onion for seed purpose is 1200 to 1300 kg bulbs/ha.
Spacing : 60 x 15 or 75 x 20 cm.
Manuring:
1. The dose of FYM is 25 to 30 tons/ha.
2. The dose of fertilizer is 50 kg N : 25kg P2O5 and 50kg K2O/ha.
3. 25kg N and all P and K is given as basal dos at the time of planting.
4. Remaining 25kg N is given as top dressing one month after planting.
Irrigation:
1. First irrigation is given just before or after planting.
2. Second irrigation is given 3 to 4 days after planting.
3. Other irrigations are given at an interval of 10 to 12 days.
4. In all 14 to 16 irrigations are needed.
Intercultivation:
1. Weeding is done for two to three times at 15 to 20 days interval.
2. One earthing up is given one month after planting.
Harvesting:
1. Each bulb bears 4 to 5 flower heads but all the flower head doesn’t mature at same time.
2. Flower heads begin to mature in about 90 to 105 days after planting.
3. Harvesting of only fully matured heads is done at 3 to 4 days interval.
4. It is continued for 30 to 40 days.
5. The heads are dried in sun and then rubbed by hand or beaten its stick.
6. Winnowing is done to separate the seed from husk.
Yield:
1. Av. Yield of seed is – 500 – 600kg/ha.
2. Av. Yield of bulb is – 5000 – 6000 kg/ha.