Zhang-Qiao, WANG Jing-er, LIN Jun, YAN Shu-Feng, WU Da-Peng, QIN Li, CHEN Jin-Hong, HONG Cai-Xia, ZHU Shui-Jin
Cotton Science. 2010, 22(1): 3-9.
The effects of the three different gelling agents, agar, gelrite and Phytagel, on callus inducing, embryogenic callus amplification, the somatic embryogenesis and plant regeneration of upland cotton (Gossypium hirsutum L.) germplasms, Coker 312 and TM-1, were studied systematically, using the system of upland cotton somatic culture developed in our laboratory. The results showed that the phytagel which used as the gelling agent for the medium of somatic culture could improve the browning problem during the somatic culture, increase the amplification of embryogenic callus, and improve the quality of the callus and embryogenic callus, which led to significantly increasing in somatic embryogenesis and plant regeneration. So the phytagel is a good gelling agent for medium of somatic culture in upland cotton. Although the gelrite also can solve the problem of the browning during the somatic culture, due to its hydrating process during the culture which may affect the amplification of embryogenic callus and somatic embryogenesis seriously, the results of gelrite is not as good as phytagel. Combination with the method of somatic culture system optimized by our laboratory recently, the regeneration plants from 10 upland cotton genotypes, included the genotypes called the recalcitrant nature in plant regeneration, were obtained in a relative short period of culture, using the Phytagel as the gelling agent. Therefore, it is suggested that Phytagel should be used as the gelling agent in the media for inducing embryogenic callus, somatic embryogenesis, and plant regeneration during the somatic culture of upland cotton, especially for the genotypes with recalcitrant nature in plant regeneration. While for the culture of germ-free seedlings and callus inducing, the agar is still a good gelling agent because of the economic reason.
