1. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems After completing this lesson, you have learned to answer: 1.Define ratoon cropping? 2.What are the advantages of ratoon cropping? 3.What are the disadvantages of ratoon cropping? 4.Describe the good practices for ratooning of sorghum? 5.List useful varieties for sorghum ratoon cropping? Lesson 3: Ratoon Cropping Virtual Academy for the Semi Arid Tropics Module 7: Cropping Systems Lessons Course on Sorghum Production Practices Modules

2. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping Ratoon cropping is the technique of allowing a crop to produce two crops of yield from one planting. The principles involved in ratoon cropping are that the ratoon crop has well developed root system, earlier maturity, and the perennial nature.

3. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping The advantages of ratoon cropping are: Reduced cost of production through savings in land preparation and care for the plant; Reduced crop cycle: crop planted less often, so replanting cycle is longer; Better use of growing season;

4. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping The advantages of ratoon cropping are: Higher yield per unit area in a given period of time; Less use of irrigation water and fertilizer than main (original) crop because of a shorter growing period.

5. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping Recently, the ratooning of kharif sorghum is becoming popular. Ratooning of kharif sorghum becomes successful if little care is taken at the time of harvest of original crop of sorghum. With adequate rainfall, a second crop of grain (usually 40 to 50 percent less than the yield potential of the planted crop) may be produced. It is likely that insect pressure will be heavy on this second crop.

6. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping For taking ratoon crop of sorghum: Main crop should be cut at 1-4 cm height above the ground level after its maturity. When cutting the stubble, make sure the mower blades are sharp. Shattered, split, or broken stalks may not put on new growth. The field need to be cleaned by removing diseased and damaged plants, weeds and dried leaves etc. This should be completed within 4-5 days after harvest of the main crop.

7. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping Mix in the soil 25 kg N and 20-25 kg P 2 O 5 /ha using a blade hoe in between two lines. The crop should be irrigated immediately after the application of fertilizers, if there are no rains. Spray 0.04% Endosulphan 35 EC seven days after the harvest of main crop to control shoot fly.

8. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping The excess tillers are removed when they are of 25-30 days old by keeping only 2-3 tillers per plant. It is necessary to remove new tillers again for 2-3 times. Second dose of N should by given 25-30 days after first dose. The crop need to be irrigated once in 15-20 days up to the grain filling stage. Stop irrigation on 70-80 days after ratooning.

9. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping The varieties recommended for ratoon crop are CSH-1, CSH-5 and CSH-6. CO25, CO 26, CSH 5, and K Tall are recommended in Tamil Nadu The CSH-9 variety is not recommended for taking ratoon crop.

10. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 7: Cropping Systems Lesson 3: Ratoon Cropping Harvest the crop when the grains turn yellow. The duration of the ratoon crop is about 15 days less than the main crop. The yield of ratoon sorghum could be about 2500-3000 kg/ha depending upon the variety, soil type and management of the crop.