‘Khaira disease of rice’ is caused due to the deficiency of

• A. Zinc deficiency
• B. Boron deficiency
• C. Magnesium deficiency
• D. All of the above

Khaira disease of rice is primarily linked to a deficiency in zinc. Therefore, the correct answer to your question is A. Zinc deficiency. However, it's important to understand the broader context of nutrient deficiencies in rice cultivation and how they can affect plant health.

Understanding Khaira Disease

Khaira disease is a significant issue in rice production, particularly in regions where zinc levels in the soil are low. This disease manifests through various symptoms, including stunted growth, yellowing of leaves, and poor grain development. The primary culprit here is zinc, which plays a crucial role in various physiological processes within the plant.

The Role of Zinc in Rice Growth

Zinc is an essential micronutrient that contributes to:

• Enzyme Function: Zinc is a cofactor for numerous enzymes involved in carbohydrate metabolism and protein synthesis.
• Photosynthesis: It helps in the formation of chlorophyll, which is vital for photosynthesis.
• Hormonal Regulation: Zinc influences the production of growth hormones, which are crucial for plant development.

When rice plants lack sufficient zinc, they cannot perform these functions effectively, leading to the symptoms associated with Khaira disease.

Other Nutrient Deficiencies

While zinc is the primary nutrient associated with Khaira disease, deficiencies in other nutrients like boron and magnesium can also affect rice health, though they are not directly linked to this specific disease. Here's a brief overview:

Boron Deficiency

Boron is important for cell wall formation and reproductive development in plants. A deficiency can lead to poor grain filling and reduced yield, but it does not cause Khaira disease.

Magnesium Deficiency

Magnesium is vital for chlorophyll production and overall plant vigor. Deficiency symptoms include interveinal chlorosis (yellowing between leaf veins) and leaf curling. While magnesium deficiency can impact rice health, it is not the cause of Khaira disease.

Conclusion

In summary, while Khaira disease is specifically caused by zinc deficiency, it's essential to maintain a balanced nutrient profile in rice cultivation. Addressing zinc deficiency through soil amendments or foliar sprays can help mitigate the risk of Khaira disease and promote healthier rice plants. Regular soil testing and appropriate fertilization strategies are key to ensuring optimal nutrient levels for rice production.