Given below are two statements: Assertion (A): Khaira disease is a prominent nutrient deficiency found in paddy crop. Reason (R): Khaira disease of rice derives its name from dark reddish brown pigmentation of the leaves of the Zn deficient plant.

Correct option is A

Khaira disease is a well-known nutrient deficiency disorder occurring in rice crop under certain soil conditions. It is caused due to zinc deficiency, which affects enzymatic activities and normal plant metabolism. The disease is characterized by dark reddish brown pigmentation that appears initially in the middle of leaves. Therefore, the reason correctly explains the assertion regarding Khaira disease in paddy.
Information booster: Khaira disease commonly occurs in calcareous, alkaline, and poorly drained soils. Zinc deficiency leads to stunted growth, leaf discoloration, and delayed maturity in rice plants. The disease can be corrected by applying zinc sulphate through soil or foliar application. Proper micronutrient management helps in preventing nutrient disorders and yield losses.
Why other options are incorrect: (b) This option is incorrect because the reason fully explains the assertion. (c) This option is incorrect since the reason is also true. (d) This option is incorrect because both statements are scientifically correct.