Transformation of cotton somatic embryos is the time-honored method for creating transgenic cotton plants. The procedure is limited by the well-known recalcitrance of many elite cotton varieties to undergo regeneration in vitro. Previous studies by scientists at the Institute of Genetics and Plant Experimental Biology showed that small protuberances of tissue are present transiently on many organs of young cotton plants (petiole, leaf, cotyledons, meristems, and roots). The morphological similarity to zygotic embryos suggested that these “natural somatic embryoids” might develop further in culture. The present study was initiated to determine the density of distribution of these “natural somatic embryoids” on plants, the period of existence, size, and structure. Embryoids were investigated from Gossypium hirsutum, Coker 312, the cultivar that regenerates with highest frequency, in a G. hirsutum adapted to Uzbekistan, Ë-470, and several other cotton species (G.barbadense ssp.ruderale, G.tomentosum, G.mustelinum and its multigenomic diploids such as G.thurberi, G.davidsonii, G.raimondii, G.harknessii, G. arboreum and G.herbaceum.

“Natural somatic embryoids” were harvested from plants and placed in defined tissue culture conditions. Some, although not all, of the embryoids were capable of developing in tissue culture. The intent of our future work will be to identify optimal conditions for regenerating cotton from “natural somatic embryoids” and comparing the morphology, cytology, and biochemistry of somatic and zygotic development in cotton.