Mark the incorrect statement w.r.t. layering.

Options

A. It is carried out on one year old basal shoot branches commonly during summer or autumn season
B. In trench layering, basal branch is pegged in a horizontal position which develops into a number of vertical shoots
C. Tip layering is artificial method of vegetative reproduction in blackberry
D. In air layering, grafting clay is made of one part cow dung, one part linely cut hay or moss and two parts clay

Answer

To solve the question regarding the incorrect statement about layering, we will analyze each option step by step.

### Step 1: Analyze the First Statement
**Statement:** "It is carried out on one year old basal shoot branches commonly during summer or autumn season."

- **Evaluation:** This statement is incorrect. Layering is typically performed on one-year-old basal shoot branches during early spring or early rainy season, not during summer or autumn.

### Step 2: Analyze the Second Statement
**Statement:** "In trench layering, basal branch is pegged into a horizontal position which develops into a number of vertical shoots."

- **Evaluation:** This statement is correct. In trench layering, the basal branch is indeed pegged into a horizontal position, which allows it to develop multiple vertical shoots.

### Step 3: Analyze the Third Statement
**Statement:** "Tip layering is an artificial method of vegetative reproduction in blackberry."

- **Evaluation:** This statement is also correct. Tip layering is a recognized method of vegetative reproduction used in blackberries.

### Step 4: Analyze the Fourth Statement
**Statement:** "In air layering, grafting clay is made up of first cow dung which is of one part, second linearly cut hay or moss, and third is two parts of clay."

- **Evaluation:** This statement is correct. The composition of grafting clay in air layering typically includes cow dung, moss or hay, and clay in the specified proportions.

### Conclusion
After evaluating all the statements, the incorrect statement is the first one: "It is carried out on one year old basal shoot branches commonly during summer or autumn season."

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