Soil and Water Conservation
Findings in water management research
- Micro sprinkler irrigation once in two days at 40 per cent pan evaporation (PE) under paired row planting with a spacing of 0.75 m between rows and 1.25 m between pairs of rows was found to be optimum in sandy loam soils with following time of operations.
| Season | Time of operation | |
|---|---|---|
| January-February | : | 1 hour |
| March-June | : | 1 hour 30 minutes |
| July-September | : | 1 hour |
| October-November | : | 45 minutes |
Single economic drip irrigation layout of 1.50 m lateral spacing with 4 lph drippers at 60 cm spacing along the lateral is most suitable for sugarcane, banana, turmeric, tapioca, tomato and other annual crops without altering the layout for several years.
Triangular method of planting – Banana
Paired row method – Sugarcane
Paired row method – Tapioca
Raised bed method – Turmeric
- Drip fertigation at 100 per cent of recommended Nitrogen and Potassium is very much suitable to sugarcane, banana, turmeric, tapioca and tomato.
- In banana based inter cropping system with marigold as intercrop, irrigation at 0.8 IW/CPE (approximately 6-8 days interval) registered higher fruit yield, total equivalent yield, WUE and B-C ratio.
- Pit method (3 plants/pit) of banana planting with drip irrigation and fertigation of N and K application of 84 lits of water through drip once in two days is found to give higher yield, WUE and economic returns.
Water requirement of different crops
Rice
- Irrigation to a depth of 5 cm water once in 4 days (or) 1-2 days after disappearance of ponded water saves 30 per cent water over continuous submergence.
Sorghum
- Irrigation reqirement is 500 mm and the critical stages are vegetative, flowering and doughening / maturity stages.
Bajra
- Irrigation requirement is 400 mm and the critical stages are tillering, flowering and maturity stages.
Maize
- Irrigation requirement is 550 mm and the critical stages are knee height, tasseling, silking and maturity.
Pulses
- Irrigation requirement is 350 mm (based on 0.6 IW/CPE ratio, 10-12 days interval) and critical stage is flowering phase.
Groundnut
- Irrigation requirement is 550 mm, (in view of 0.6 IW/CPE ratio i.e. irrigation at once in 10-12 days interval). Border strip method of irrigation saved 22.3 per cent irrigation water.
Sunflower
- Irrigation at 10-12 days interval (0.6 IW/CPE ratio) with alternate furrow irrigation required only 450 mm of water.
Cotton
- Irrigation requirement is 650 mm. Flowering, boll formation and boll development stages are the critical stages.
Sugarcane
- Irrigation requirement is 1800 mm (surface method); Drip once in 2 days at 0.30 IW/CPE consumed only 1028 mm water.
Turmeric
- Surface irrigation required 1390 mm of water but drip irrigation daily at 45 minutes to 1 ½ hrs depending on weather (0.36 IW/CPE ratio) consumed only 650 mm of water.
Banana
- Surface irrigation consumed 2500 mm of water. Whereas drip irrigation once in 2 days at 24 litre/plant consumed 1081 mm of water.
Tapioca
- Irrigation requirement is 1400 mm. Irrigation through drip once in 2 days saves 50 per cent of water.