1. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers At the end of this Lesson, you will be able to answer: 1.What should be the basis for deciding the amount of manures and fertilizers to sorghum? 2.What is the recommended rate of organic manures for sorghum? 3.What is the nitrogen, phosphorus and potassium recommendation for sorghum? 4.When do you apply nitrogen in two doses? 5.What is the method of application of phosphatic fertilizers? 6.How do you apply recommended dose of potassium?

2. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers Prior to the availability of improved varieties and sorghum hybrids, very little fertilizers were used with consequent low sorghum yields. With the cultivation of high yielding varieties and hybrids, fertilizer application is essential to get the yield potential of these cultivars.

3. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers A soil test is the most practical method of determining fertilizer needs of sorghum crop. However, in the absence of soil test results, the recommended fertilizer application need to be followed.

4. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers For rain fed crop 6-7.5 tones of Farm Yard Manure (FYM) need to be applied before last ploughing and then properly incorporated. For hybrids and high yielding varieties cultivated under irrigated conditions, the dose of FYM or compost needs to be doubled i.e. 12- 15 tones/ha. Azospirillum, a biofertilizer, is recommended to at 2 kg/ha mixed with each of 25 kg of FYM and soil, and applied at the final ploughing or at sowing.

5. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers Sorghum responds profitably to a balanced fertilizer application program. Soil testing to know about the nutrient availability is the first step towards balanced fertilizer program that do not waste fertilizer by applying nutrients that are already sufficient for the anticipated level of production. Balanced fertility program improves water use efficiency, drought-tolerance, and grain yield at the lowest possible cost.

6. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers Under dry land conditions with low rainfall 30 to 60 kg/ha of nitrogen may be adequate for varieties of low yield potential. For long-season, high rainfall or irrigated areas may require 100 to 120 kg N/ha to get higher yields. Recommended rate of nitrogen is applied in two equal split doses in light soils. The first application is done at sowing and the second one 25 to 30 days after planting.

7. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers Soil tests showing low and very low phosphorous (P) indicate an expected response to phosphorous application, unless yield potential is restricted by insufficient moisture. Response has been erratic with medium testing soil and is unlikely when soil tests are high or very high. The recommended rate of phosphorus application is 25 kg P 2 O 5 /ha for rainfed sorghum and 45 to 50 kg P 2 O 5 /ha for irrigated sorghum.

8. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers The recommended rate of phosphorus is applied in one dose, and along with nitrogen fertilizer at the time of sowing. Phosphorus has to be applied as side dressing or by placement below the seed for its efficient utilization of plants.

9. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition Lesson 4: Application of manures and fertilizers Soils with medium or above in potassium will not normally show a yield response to added potassium fertilizer. For soils low in potassium (less than 150 kg/ha), the recommended rates are 25 kg/ha of K 2 0 for rainfed sorghum and 50 kg/ha of K 2 0 for irrigated sorghum. Like phosphorus, potassium also is applied in one dose at the time of sowing along with nitrogen fertilizer.

10. Virtual Academy for the Semi Arid Tropics Course on Insect Pests of Groundnut Module 5: Sorghum Plant Nutrition With this, the Lesson 4 on Application of manures and fertilizers, and also this Module 5 on Sorghum Plant Nutrition concludes. If you would like to test your understanding about sorghum plant nutrition, please click “Exercise” button. The next Module in this Course deals with the nutrient deficiency symptoms in sorghum. Click on the ‘Modules’ button to select Module 6 Lesson 4: Application of manures and fertilizers Virtual Academy for the Semi Arid Tropics Course on Sorghum Production Practices Module 5: Sorghum Plant Nutrition LessonsExerciseModules