Gray spots of oat are caused by the deficiency of

Options

A. Cu
B. Zn
C. Mn
D. Fe

Answer

To solve the question regarding the cause of gray spots in oats, we can follow these steps:

### Step 1: Understand the Question
The question asks about the deficiency that leads to gray spots in oats. We need to identify which mineral deficiency is responsible for this condition.

### Step 2: Identify the Condition
The gray spots in oats are referred to as "gray spot disease." This is a specific condition that affects the oat plant.

### Step 3: Research the Causes
We need to find out what causes gray spot disease in oats. This involves looking into the mineral nutrition of plants and understanding which deficiencies lead to this particular symptom.

### Step 4: Determine the Deficient Mineral
Upon researching, we find that gray spot disease in oats is specifically caused by a deficiency of manganese (Mn).

### Step 5: List the Symptoms
The symptoms associated with gray spot disease include:
- Grayish-brown elongated specks and streaks on the leaves.
- Empty panicles (the flowering part of the plant).
- Intervenal chlorosis on stems and leaves (yellowing between the veins).

### Step 6: Conclude the Answer
Based on the information gathered, we conclude that the gray spots of oats are caused by the deficiency of manganese. Therefore, the correct answer is option C: manganese (Mn).

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