Q.Define cybrid.

A protoplast is a plant cell that has had its rigid cell wall removed but still retains an intact plasma membrane, and because the wall is gone, protoplasts can be induced to fuse with one another in ways walled cells cannot. Protoplasts are isolated, typically from leaf tissue, by digesting the cell wall with a mixture of enzymes (such as Macrozyme and Onozuka cellulase) dissolved in an osmotic stabiliser (sorbitol or mannitol), then separating the released protoplasts from cell-wall debris by centrifugation. Fusion between two protoplasts - often from different species - is triggered using a fusogen, most commonly polyethylene glycol (PEG) together with calcium ions, which causes the protoplasts to agglutinate and merge. Once fused (or unfused but freshly isolated), protoplasts are cultured in MS liquid medium using specialised techniques such as droplet culture or plating, under continuous light, until they regenerate a new cell wall (within 24-48 …