Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Virtual Academy for the Semi Arid Tropics Lesson 4. Deficiency Symptoms of Micronutrients After successful completion of 5 Units in this Lesson, you will be able to answer: Under what soil conditions the deficiencies of each micronutrient occur? Describe the plant symptoms due to nutrient deficiencies of each micronutrient nutrient in sorghum crop? Course on Sorghum Production Practices

Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Virtual Academy for the Semi Arid Tropics Lesson 4. Deficiency Symptoms of Micronutrients The 5 Units in this Lesson are: Unit 1: Iron Deficiency Symptoms Unit 2: Zinc Deficiency Symptoms Unit 3: Boron Deficiency Symptoms Unit 4: Copper Deficiency Symptoms Unit 5: Manganese Deficiency Symptoms Course on Sorghum Production Practices

After successful completion of this Unit you should be able to answer Under what conditions zinc deficiency results in sorghum? Describe the leaf symptoms due to zinc deficiency in sorghum? How the sorghum plants look in zinc deficient field? How do you identify zinc deficiency symptoms from that of iron deficiency symptoms?

Zinc (Zn) deficiency is likely to occur when soils are alkaline or low in organic matter, under high levels of soil Phosphorus, and when the soils are cool and wet during the vegetative phase.

Sometimes zinc (Zn) may be present in the soil, but not available to plants. A high soil pH, or a calcareous soil means that zinc is less available (soluble). Crops under these soil conditions may suffer from zinc deficiency.

Zinc deficiency causes the internodes to become very short, resulting in stunted plants. The first symptoms on the foliage appear on the youngest leaves even before they unroll from the whorl. Observe the stunted plant and shortened internodes.

The mid-vein and margins usually remain green. Pale yellow chlorosis develops between the margins and mid-vein near the base of the leaf blade. The mid-vein and margins usually remain green. Observe pale yellow chlorosis on young leaves.

In some cultivars, a reddish-purple or brown pigmentation develops adjacent to the yellow chlorosis in the basal tissue of the blades of the young leaves.

Zinc and Iron deficiency symptoms can be confused. However Iron chlorosis extends to full length of leaves (left Fig.) where as chlorosis due to Zinc deficiency occur mainly on the lower half of the leaves (top Fig.).

Course on Sorghum Production Practices Module VI: Plant Nutrient Deficiency Symptoms Virtual Academy for the Semi Arid Tropics Lesson 4. Deficiency Symptoms of Micronutrients With this, the Unit 2 on Zinc Deficiency Symptoms in sorghum in this Lesson concludes. In the subsequent units in this Lesson deficiency symptoms of other micronutrients in sorghum are explained. Select Unit 3 of Lesson 4 from Module VI contents Course on Sorghum Production Practices