A New Synthetic Amphiploid (AADDAA) between Gossypium hirsutum and G. arboreum Lays the Foundation for Transferring Resistances to Verticillium and Drought

摘要: Gossypium arboreum, a cultivated cotton species (2n = 26, AA) native to Asia, possesses invaluable characteristics unavailable in the tetraploid gene pool, such as resistance pests and diseases tolerance abiotic stresses. However, it is quite difficult transfer favorable traits into Upland through conventional methods due cross-incompatibility of G. hirsutum 52, AADD) arboreum. Here, we improved an embryo rescue technique overcome between these two parents for transferring genes from arboreum hirsutum. Our results indicate that MSB2K supplemented with 0.5 mgl-1 kinetin 250 mg-1 casein hydrolysate efficient initial medium rescuing early (3 d after pollination) hybrid embryos. Eight putative hybrids were successfully obtained, which further verified characterized by cytology, molecular markers morphological analysis. The subsequently treated different concentrations colchicine solution double their chromosomes. demonstrate four plants chromosome-doubled treatment 0.1% 24 h become amphiploid, confirmed cytological observation, self-fertilization backcrossing. Preliminary assessments at seedling stage synthetic amphiploid showed highly resistant Verticillium drought. × would lay foundation developing arboreum-introgressed lines uniform genetic background acc TM-1, greatly enhance simplify mining, isolation, characterization, cloning use arboreum-specific desirable future breeding programs.