Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract Only
Publication Acceptance Date: 11/6/2007
Publication Date: N/A
Technical Abstract: Cultivated cotton and its wild relatives typically have glands on both the reproductive and vegetative parts of the plant. These glands contain compounds that are toxic to a number of insects and possibly inhibit some diseases. Unfortunately these same compounds are also detrimental to humans and non-ruminant animals. Cotton seed would be an even more valuable source of high quality protein if these toxic substances, especially gossypol, could be reduced. Totally glandless varieties have been developed, but not adopted as they leave the plant vulnerable to pests. The focus of our research is to decrease the levels of gossypol in the seed while maintaining a high enough concentration of toxins in vegetative parts of the plant to offer protection from pests. Preliminary studies indicated that crosses between cotton varieties with different gland densities and distributions produced a range of glanding patterns. By selecting within the resulting progeny, we have identified and advanced to the F7 generation, genotypes that have less than 0.30% total gossypol in the de-hulled seed, while still possessing glands at critical locations on the vegetative plant parts. Fiber quality analyses indicated that fiber properties have been maintained or improved compared to the parental lines. In 2006 and 2007, four of these lines were tested in replicated yield trials. As our elite lines do not contain transgenes, they are subject to fewer governmental regulations. These non-GMO lines will be a valuable source of germplasm for developing low seed gossypol cultivars. Seed from these cultivars would provide a new source of inexpensive protein for animal feeding rations.