Question

what is callus .name its colour

Answer 1

Green colour develops due to development of chloroplastid in the cells of callus tissue e.g. callus tissue from the cotyledons of the soya bean. Callus may be yellow possibly due to synthesis of carotenoid pigments, e.g. callus tissue of Nigella sativa grown under dark condition

Answer 2

Callus (cell biology) From Wikipedia, the free encyclopedia. Plant callus (plural calluses or calli) is a growing mass of unorganized plant parenchyma cells. In living plants, callus cells are those cells that cover a plant wound.

Callus may be yellow possibly due to synthesis of carotenoid pigments, e.g. callus tissue of Nigella sativa grown under dark condition.