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"" are sprayed on the cotton fields to...

`"_________"` are sprayed on the cotton fields to defoliate and hence facilitate machine picking of bolls.

A

antiauxins

B

sodium salts of NAA

C

naphthalene acetic acid & related auxins

D

herbicides

Text Solution

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The correct Answer is:
To answer the question, we need to identify the chemical that is sprayed on cotton fields to defoliate the plants, which helps in the mechanical picking of cotton bolls. ### Step-by-Step Solution: 1. **Understanding the Purpose**: The question states that a chemical is used to defoliate cotton plants. Defoliation is the process of removing leaves from plants, which is essential for improving the efficiency of machine harvesting. 2. **Identifying Defoliants**: Defoliants are chemicals that promote the shedding of leaves. They are often used in agriculture to prepare crops for harvest by reducing the amount of foliage that can interfere with mechanical harvesting. 3. **Analyzing the Options**: The options provided are: - Anti-oxidants - Sodium salts of NAA - Naphthalene - Acetic acid and related oxides - Herbicides 4. **Evaluating Each Option**: - **Anti-oxidants**: These are not typically used for defoliation. - **Sodium salts of NAA**: This is a plant growth regulator but not commonly used for defoliation. - **Naphthalene**: This is not a standard defoliant. - **Acetic acid and related oxides**: While acetic acid has various uses, it is not primarily known as a defoliant. - **Herbicides**: These are used to kill unwanted plants, not specifically for defoliation. 5. **Correct Choice**: The correct answer is **Sodium salts of NAA** (Naphthalene Acetic Acid), which is known to be used as a defoliant in cotton fields to facilitate machine picking of bolls. ### Final Answer: **Sodium salts of NAA** are sprayed on the cotton fields to defoliate and hence facilitate machine picking of bolls.
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