Fig. 3

Somatic embryo induction and embryonic cell regeneration of embryonic callus A: After three generations, the green spherical callus was observed to contain a small number of embryonic cells. B: After five successive generations, the callus differentiated the embryonic callus cell population. C: The embryonic callus after 6 successive generations; D: After 7 generations, the somatic embryo matured and the callus showed polyembryonal stalks. a: The green callus that has not been sub-cultured in time in the initial culture gradually dried up and turned brown, and some cells even died; b: After being sub-cultured 25 d, white callus appears on the edge of brown callus. c: After two successive generations of 60 d, a dark green, spherically dense callus was formed. d: After 45 days of subculture, embryonic cells began to form on the callus edge