Question

Write a short note on protoplast fusion.

Answer 1

Protoplast fusion is a technique where protoplasts (cells without cell walls) from two different plant species or varieties are fused to form a hybrid cell. This hybrid cell contains the nuclear genome of one species and cytoplasm (including organelles) from another or both, creating cybrids. It helps create new crop varieties by combining desirable traits from incompatible plants.

Steps include isolation of protoplasts, mixing with fusogenic chemicals (like polyethylene glycol) or applying electric fields (electrofusion), fusion of protoplast membranes, fusion of nuclei, regeneration of cell walls, and growing into hybrid plants.

Protoplast fusion is important in plant breeding to overcome sexual incompatibility and introduce traits like male sterility and herbicide resistance in crops.