Introduction to Major Field Crops

Sowing

Time of Sowing
The rate of development of oil in seed is greatly influenced by the variation in atmospheric temperature, humidity and other biotic factors. Hence, sowing either too early or too late has been reported to be harmful. Toria should be sown from the mid to the last week of September. If sowing is delayed, there is great danger of attack of aphids on this crop. Sowing ofsarson and rai must be completed in the first fortnight of October.

Seed Rate
Pure crop of rape seed and mustard can be sown with 5-6 kg seeds/ha. If crop are sown as mixed or intercropped with other crops seed rate of 1.5-2.0 kg/ha is sufficient depending upon the row ratio.

Spacing
Generally toria is sown in rows of 30 cm apart while sarson and rai are sown in rows of 45 cm apart. Thinning is done three weeks after sowing to maintain aplant to plant distance of 10-15 cm.

Method of Sowing
In irrigated conditions sowing is done with seed-cum-fertilizer drill. Fertilizer should be drilled at 7-10 cm deep and seeds are placed at 3-4 cm. The crop can also be sown by country plough by pora method (putting seeds behind the plough through funnel tube) or ridge seeder.



Fig: A view of mustard field.