1. After successful completion of 3 Units in this Lesson, you will be able to answer: 1.Under what soil conditions the nutrient deficiencies of each secondary nutrient occur? 2.Describe the plant symptoms due to nutrient deficiencies of each secondary nutrient in sorghum crop? Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms

2. The 3 Units in this Lesson are: Unit 1: Calcium Deficiency Symptoms Unit 2: Sulfur Deficiency Symptoms Unit 3: Magnesium Deficiency Symptoms Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms

3. Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Unit 3: Magnesium Deficiency Symptoms After successful completion of this Unit, you should be able to answer: 1.Under what conditions magnesium deficiency results in sorghum? 2.Describe the leaf symptoms due to magnesium deficiency in sorghum? 3.How the sorghum plants look in magnesium deficient field?

4. Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Unit 3: Magnesium Deficiency Symptoms As magnesium is not held tightly in soils, it is more susceptible to leaching losses from the root zone. Magnesium deficiency is most prevalent on sandy-textured soils, which are subject to leaching, particularly during seasons of excess rainfall.

5. Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Unit 3: Magnesium Deficiency Symptoms The leaves are usually pale green to yellow in color with many brown lesions. The symptoms develop firstly on older leaves and advance upwards to younger leaves. Observe pale green to yellow leaves.

6. Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Unit 3: Magnesium Deficiency Symptoms The predominant symptom is dark green veins with yellow areas between the veins (interveinal chlorosis). In some sorghum cultivars, orange, purple, or brown lesions develop within the chlorotic tissues. Observe dark green veins with yellow areas.

7. Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Unit 3: Magnesium Deficiency Symptoms Eventually these lesions expand and often join together until the margins of the leaf turn orange, red, or purple in color, depending on the degree of pigmentation. When the deficiency is very severe, the margins of the older leaves turn brown, wither, and die. Note the uniform yellow color of the leaf with prominent brown and purple lesions.

8. Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Unit 3: Magnesium Deficiency Symptoms The symptoms developed by some diseases may be confused with the orange, purple, or brown lesion symptoms appearing in sorghum when magnesium is deficient. These diseases include leaf blight and oval leaf spot. However, these diseases never cause the development of interveinal chlorosis or marginal necrosis which occurs when magnesium is deficient.

9. With this, the Unit 3 on Magnesium Deficiency Symptoms and the Lesson on Deficiency symptoms of Secondary Nutrients in sorghum concludes. The next Lesson in this Module is about deficiency symptoms of micronutrients in sorghum. Select the Lesson 4 from Module VI contents Virtual Academy for the Semi Arid Tropics Lesson 3. Deficiency Symptoms of Secondary Nutrients Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms