Which one of the following statement concerning growth regulators is incorrect .

Options

A. Gibberellins cause the formation of more male flowers in Cannabis
B. Abscisic acid manitains seeds in a dormant state
C. Cytokinins increase the K + concentration in guard cells
D. Some synthetic auxins control grass weeds in pulse crops

Answer

To determine which statement concerning growth regulators is incorrect, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand the Role of Growth Regulators:**
- Growth regulators, also known as phytohormones, are substances that regulate various physiological processes in plants, including growth, flowering, and fruit ripening.

2. **Evaluate Each Statement:**
- **Option A:** "Gibberellins cause the formation of more male flowers in cannabis."
- Gibberellins are known to influence flowering and can promote male flower formation in certain plants, including cannabis. This statement is likely correct.

- **Option B:** "Abscisic acid maintains seeds in a dormant state."
- Abscisic acid (ABA) is indeed known for its role in promoting seed dormancy. This statement is also likely correct.

- **Option C:** "Cytokinins increase the K-plus concentration in the gut cells."
- Cytokinins are involved in cell division and growth, but the specific claim regarding increasing K-plus concentration in gut cells lacks clear evidence and is likely incorrect.

- **Option D:** "Some synthetic auxins control grass weeds in the pulse crops."
- Synthetic auxins are commonly used as herbicides to control broadleaf weeds, but their effectiveness on grass weeds is limited. This statement is also likely incorrect.

3. **Identify the Incorrect Statement:**
- After evaluating all four options, we find that **Option C** is the most questionable due to its lack of clear evidence regarding the effect of cytokinins on K-plus concentration in gut cells. However, Option D is also problematic because synthetic auxins do not effectively control grass weeds in pulse crops.

4. **Conclusion:**
- The incorrect statement concerning growth regulators is **Option D**: "Some synthetic auxins control grass weeds in the pulse crops."

### Final Answer:
**Option D** is the incorrect statement.

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