Ontogeny of Cotton Seeds: Gametogenesis, Embryogenesis, Germination, and Seedling Growth

Abstract

Production of a viable seed is of paramount importance to the survival of a plant species. Many plants, including cotton, amass large reserves of storage protein and oil in their seeds (oilseeds) to use during dormancy, germination, and seedling growth. These reserves are mobilized after imbibition when environmental conditions are favorable for growth. Due to their rich supply of protein and oil, e.g., approximately 80% of the dry weight of cottonseed kernels consists of protein and oil reserves (Doman et al., 1982), oilseeds have also been used as a human food source. The nutritional value of each oilseed variety or species differs; therefore, minor changes in either protein or oil composition could result in major nutritional improvements and increased economic value of the crop. Improving seed quality is not restricted to increasing its nutritional value; it can also be accomplished by increasing seed vigor, viability, cold tolerance, or resistance to disease. A better understanding of the cellular processes involved in the ontogeny of cottonseeds will lead to new approaches in seed improvement. Discussion of developmental events from gametogenesis to seedling growth will be presented and will focus on important processes involved in producing a viable cottonseed and plant.