Genetic Analysis ofcallusinitiation inGossypium tomentosumandGossypium darwinii

AbstractWild cotton species can contribute a valuable gene pool for the genetic improvement of cultivated tetraploid cultivars. But the obstacle is the reproductive isolation of different species. Somatic embryogenesis offers a temporary status for genetic manipulation such as somatic hybridization. The present studies aimed at optimizing the conditions for regeneration of wild species of cotton. Callus were successfully induced from hypocotyls ofGossypium tomentosum(C1genome) andGossypium darwinii(D5genome) on MSB5(MS salts and B5vitamins) medium supplemented with 0.01mg/L 2, 4-D (2, 4-dichlorophenoxyacetic acid), 0.01mg/L KT (kinetin), 0.01mg/L IAA (3-indoleacetlc acid) and 0.60mg/L 2, 4-D, 0.25mg/L KT, respectively. Plant growth regulators (PGRs) combinations, adding high inorganic salt stress, and carbohydrate were used to induce embryogenic callus from nonembryogenic callus. Embryogenic cultures were induced from the two cotton species. Based on studying the effect of PGRs, nitrogen sources, molysite, CuSO4and pH value on somatic embryogenesis (SE), we obtained somatic embryogenesis in theG. tomentosumon the medium with 0.1 mg/L 2, 4-D, 0.1 mg/L KT while deprivation of KNO3. The result gives out new exploration on somatic embryogenesis in cotton to create new germplasm sources.