Introduction to major field crops (1+1)

Sowing

Time of Sowing
Time of sowing is indirectly determined by the soil and atmospheric temperature as well as by the supply of water. Thus, there is a general preference for sowing of the crop at the time of onset of monsoon. Late planting in mid-monsoon period creates numerous problems.

Seed Rate
The quantity of seed required for dibbling method is about 15 kg/ha. However, in planting by other mechanical methods one may use as high as 25kg seeds/ha. The seed rate should be so adjusted as to obtain the desired plant population.

Spacing
To obtain desired plant population one may sow the seeds into rows spaced from 60-90 cm apart and seed to seed distance of 20-30 cm within the row. However, for practical ease a spacing of 75 x 20 cm is more appropriate which is convenient for machine drawn by tractor or bullock power.

Depth of sowing
For obtaining perfect germination and uniform stand, placement of seed at a desired depth is one of the most important factors. A uniform depth of 5.0 cm is ideal for better germination.

Method of Sowing
Three methods of sowing are commonly followed under Indian conditions.


1. Flat Sowing:On light soils crop is sown on the smooth seed bed. If necessary crop can be earthen up subsequently to avoid plant lodging.
2. Ridge Sowing: Ridges are prepared and the sowing is done on top. This system of planting is very useful under high rainfall area of heavy soil. Excess water flows through the trenches and thus contact with seed or plant is avoided.
3. Furrow Sowing:Under low moisture condition, this is one of the most effective methods of sowing. Moisture in furrows continues to be available for longer period.
4. Transplanted Maize:Can be successfully cultivated by transplanting in winter season. The nursery sown from 10-20 November can be transplanted from mid-December to mid-January. Only one month old seedling may be used for transplanting.





Fig: Mechanical seed drill. Fig: Seedling stage.





Fig: Two-leaf stage. Fig: Four-leaf stage.





Fig: Knee-hight stage.






Fig: Rapid growth stage.



Fig: Roots.



Fig: Reproductive stage. Fig: Tassels (Male).






Fig: Cob with silk (Female).






Fig: Immature cobs.



Fig: Matured cob. Fig: Types of cobs.