The deficiency of sulphur causes chlorosis first in`"________"`

Explanation

**Step-by-Step Solution:**

1. **Understanding Chlorosis**: Chlorosis is the yellowing of leaves due to insufficient chlorophyll. It is a symptom of nutrient deficiency in plants.

2. **Identifying the Nutrient**: In this case, we are focusing on the deficiency of sulfur. Sulfur is an essential nutrient for plants and plays a crucial role in the formation of chlorophyll.

3. **Observing the Pattern of Chlorosis**: When there is a sulfur deficiency, chlorosis typically begins in the younger leaves of the plant. This is because younger leaves are more actively growing and require more nutrients.

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