Genetics and morphological studies of new genetic male sterile line of cotton (Gossypium arboreum L.).

摘要

The cytomorphology and performance of hybrids based on a genetic male sterile line (GMS) of cotton developed in Rahuri, Maharashtra, India, were studied. This GMS line was characterized by pollen abortion and significant reduction in flower characters (such as petal size, and number and size of anthers). The GMS line was pollinated by fertile sibs from the same line and by other cultivars (Y1, G-27, Sanjay, Sawata, G.Cot.15, F1 (GMS-S x Y1), and G.Cot.19). The F1 progenies were selfed and backcrossed with male parents. The inheritance of sterility and fertility was studied in the F2 and BC1 generations. The male sterile anthers were smaller and less in number than the female counterpart. The pollen mother cells of male sterile and fertile flowers contained 2n=26 chromosomes, with an average of 13 bivalents. The pollen in non-dehiscent anthers was sterile. The pollen of the fertile counterpart was fully fertile. Sterility was controlled by 2 recessive genes. The hybrids obtained from crossing between the GMS line and other cultivars exhibited superior seed yield per plant, boll weight and fibre properties than the control.