Along with auxin, which PGR is used to induce proliferation of cells in callus,

Options

A. GA
B. Cytokinin
C. ABA
D. Florigen

Answer

To solve the question "Along with auxin, which PGR is used to induce proliferation of cells in callus?", we can follow these steps:

### Step 1: Understand the Terms
- **PGR**: This stands for Plant Growth Regulators, which are substances that influence plant growth and development. They can act as promoters or inhibitors of growth.

### Step 2: Identify the Role of Auxin
- **Auxin**: This is a type of PGR that primarily promotes cell elongation and is crucial for various plant growth processes, including the formation of callus tissue.

### Step 3: Identify Other Important PGRs
- In addition to auxin, there are other PGRs that play significant roles in plant growth. One of the key PGRs that works alongside auxin is **cytokinin**.

### Step 4: Understand the Function of Cytokinin
- **Cytokinin**: This PGR is known to promote cell division. When used in conjunction with auxin, it helps in the proliferation of cells, particularly in callus formation.

### Step 5: Conclude the Answer
- Therefore, the PGR that is used along with auxin to induce proliferation of cells in callus is **cytokinin**.

### Final Answer:
Cytokinin

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