COTTON EMBRYOGENESIS

Abstract

The ribosomes of the egg of cotton (Gossypium hirsutum) show a low degree of aggregation into polysome. In correlation with the beginning of fusion of the egg and sperm nuclei, these ribosomes become arranged into long helical polysomes. These helical polysomes are found surrounding the plastids and mitochondria. After the zygote nucleus has been formed, additional ribosomes appear in the cell. These ribosomes aggregate into small polysomes, but no additional helical polysomes appear to be formed. Both types of polysomes exist through the 1st divisions of the embyo, but then the helical polysomes gradually disappear. The possible relationship of these changes in polysome population to plant embryo development is discussed.