Which one of the following statements is incorrect ?

Options

A. Pollen grains of many secies cause severe allergies
B. Stored pollen in liquid nitrogen can be used in the crop breeding program.
C. Tapetum helps in the dehiscence of anther.
D. Exine of pollen grains is made up of sporopollenin

Answer

To solve the question "Which one of the following statements is incorrect?", we will analyze each option provided:

### Step 1: Analyze Option A
**Statement:** Pollen grains of many species cause severe allergies.
**Analysis:** This statement is correct. Pollen grains from various plants, especially those that are wind-pollinated, can trigger allergic reactions in sensitive individuals.

**Hint:** Consider the role of pollen in allergies and its common effects on humans.

### Step 2: Analyze Option B
**Statement:** Stored pollen grain in liquid nitrogen can be used in the crop breeding program.
**Analysis:** This statement is also correct. Storing pollen in liquid nitrogen preserves its viability, allowing it to be used later in breeding programs to enhance crop varieties.

**Hint:** Think about the importance of preserving genetic material for agricultural purposes.

### Step 3: Analyze Option C
**Statement:** Tapetum helps in the dehiscence of anther.
**Analysis:** This statement is incorrect. The tapetum is a layer of cells in the anther that provides nutrients to developing pollen grains, but it does not play a direct role in the dehiscence (the process of the anther opening to release pollen).

**Hint:** Reflect on the functions of different parts of the anther and their roles in pollen development versus release.

### Step 4: Analyze Option D
**Statement:** Exine of pollen grain is made up of sporopollenin.
**Analysis:** This statement is correct. The exine is the outer layer of the pollen grain, and it is primarily composed of sporopollenin, which is known for its durability and resistance to degradation.

**Hint:** Consider the structural components of pollen grains and their significance in plant reproduction.

### Conclusion
After analyzing all the options, we find that **Option C** is the incorrect statement. The tapetum does not help in the dehiscence of the anther.

### Final Answer
**The incorrect statement is Option C: Tapetum helps in the dehiscence of anther.**