Question

Arrange the following steps in the process of somatic hybridization in correct sequence:
A. Plating of fused protoplasts
B. Selection of hybrid cells
C. Protoplast isolation and its treatment with fusion chemical.
D. Transfer of callus to differentiation medium
E. Selection of somatic hybrid plants
Choose the correct answer from the options given below :

• A. A, B, C, D, E
• B. C, A, B, D, E
• C. B, C, D, A, E
• D. A, C, B, D, E

Hint:

Think of the process from small to big: {Isolate} cells (C) \(\rightarrow\) {Plate} and grow them (A) \(\rightarrow\) {Select} the right cells (B) \(\rightarrow\) {Differentiate} into a plant (D) \(\rightarrow\) {Select} the best plant (E).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The question requires ordering the steps involved in somatic hybridization, a technique used to create hybrid plants by fusing somatic cells.
Step 2: Detailed Explanation:
The logical sequence for this process is as follows:
C. Protoplast isolation and its treatment with fusion chemical. The first step is to obtain the cells and remove their cell walls to create protoplasts. Then, a fusogen (like PEG) is applied to induce fusion.
A. Plating of fused protoplasts. The mixture containing fused and unfused protoplasts is plated on a culture medium to allow cell wall regeneration and cell division.
B. Selection of hybrid cells. Not all cells will fuse correctly. A selection method must be applied to identify and isolate the true hybrid cells (heterokaryons) from the parental cells and homokaryons.
D. Transfer of callus to differentiation medium. The selected hybrid cells are grown into an undifferentiated mass called a callus. This callus is then transferred to a medium containing specific hormones to induce the formation of shoots and roots (organogenesis).
E. Selection of somatic hybrid plants. Once plantlets are regenerated, they are often further analyzed and selected to confirm they are true hybrids and possess the desired combination of traits.
This logical flow gives the sequence: C \(\rightarrow\) A \(\rightarrow\) B \(\rightarrow\) D \(\rightarrow\) E.
Step 3: Final Answer:
The correct sequence for somatic hybridization is C, A, B, D, E.