Maize generates resistance against stem borers by having

Options

A. (a) low aspartic acid, high nitrogen and sugar content
B. (b) low aspartic acid and sugar but high nitrogen content
C. (c) high aspartic acid and nitrogen but low sugar content
D. (d) high aspartic acid, low nitrogen and sugar content.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Problem:**
- The question asks how maize generates resistance against stem borers. Stem borers are insects that damage maize by creating holes in the stems.

2. **Identifying the Technology:**
- Scientists have used recombinant DNA technology to enhance maize's resistance to stem borers. This technology allows for the modification of the plant's genes to meet specific needs.

3. **Mechanisms of Resistance:**
- There are three main mechanisms through which maize can develop resistance:
- **Morphological:** Changes in the plant's structure to make it less attractive or accessible to pests (e.g., waxy coatings).
- **Biochemical:** Alterations in the plant's metabolic pathways to produce specific compounds that deter pests.
- **Physiological:** Changes that lead to the production of toxins or other substances that inhibit pest effects.

4. **Analyzing the Options:**
- The options provided relate to the biochemical pathway. We need to determine which combination of aspartic acid, nitrogen, and sugar content is correct for maize's resistance.
- The options are:
- A: Low aspartic, high nitrogen, and sugar
- B: Low aspartic and sugar but high nitrogen
- C: High aspartic and nitrogen but low sugar content
- D: High aspartic acid and low nitrogen and low sugar content

5. **Selecting the Correct Option:**
- Based on the understanding of biochemical pathways and the modifications made to maize, the correct answer is option D: high aspartic acid and low nitrogen and low sugar content. This combination is known to enhance resistance against stem borers.

**Final Answer:**
- Maize generates resistance against stem borers by having high aspartic acid and low nitrogen and low sugar content (Option D).

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