Six haploid plants were obtained in M₂ generation of the 25 kr. x-ray irradiatedGossypium hirsutum L. cotton variety H.G. 108. The cytomorphological studies on these plants indicated highly irregular meiosis, giving on an average six bivalents, the range being 0–9. Unequal separation of chromosomes and chromatids at anaphase-I and II respectively led to formation of abnormal tetrads and pollens with high size variations leading to high pollen sterility. These plants were characterized by miniature stature, shorter stem and internodes, smaller leaves, flowers and stomata with fewer chloroplasts, male and female sterility and halving of chromosomes. The reduction in morphological characters was nearly in the proportion of 1∶2 as compared to their diploid counterparts.

Development of anther tapetum from premeiotic stages to pollen formation was studied in six x-ray induced haploids ofGossypium hirsutum, three interspecific F₂ haploids, and one natural haploid of each ofG. hirsutum andG. barbadense, and the observations were compared with those of their respective parents, a genetic male sterile, a male fertile and a cytoplasmic male sterile line ofG. hirsutum. Significant differences were recorded for number of anthers per flower, pollen size, pollen viability and number of microspores produced byPMC. Anther development in haploids was normal. Anther dehiscence was also normal in some haploids. Non-dehiscent anthers could be mostly attributed to the formation of immature pollen grains. Normal development of anthers and degeneration of tapetum occurred in the parents and in the genetic fertile line. Contrastingly no degeneration of tapetum was noticed in the cytoplasmic male sterile line.