Submitted to: Journal of Plant Registrations
Publication Type: Germplasm Registration
Publication Acceptance Date: September 4, 2012
Publication Date: May 1, 2013
Citation: Bechere, E., Meredith Jr, W.R., Boykin Jr, J.C. 2013. Registration of mutant population of MD 15 M4 Gossypium hirsutum L. with enhanced fiber quality. Journal of Plant Registrations. 7(2)216-219. Interpretive Summary: Modern upland cotton has reduced genetic variability that breeders can exploit in developing good quality and high yield cotton. Various researches have shown that chemically induced mutants can be used to overcome this problem. The objective of this research was to test the performance of a Delta cotton cultivar and its chemically induced mutant to test if new variants have been created by chemical mutagenesis. Significant differences were observed for fiber length, fiber strength, lint percent, micronaire, and seed index between the genotype MD 15 (an enhanced fiber strength cotton genotype developed by USDA in 2006) and its mutant MD 15 M4. Some individual plants selected from the mutant population had fiber length of 34.3 millimeters (as compared to 31.5 millimeters for a random plant from MD 15). Significantly stronger fibers were also observed in some individual mutant plants. Cotton breeders can use these new cotton lines to develop cotton varieties with better fiber qualities.
Technical Abstract: Mutant population of MD 15 M4 (Reg. No. ,PI ) is a unique germplasm population of upland cotton (Gossypium hirsutum L.). This germplasm was developed by USDA-ARS, Stoneville, MS in 2008 and released in June, 2012. About 5000 seeds of a Mississippi Delta line, MD 15 were chemically mutagenized with 3.2 % v/v of Ethyl Methanesulfonate (EMS). The treated seeds were hand planted in the field at Lubbock, TX in 2008 to produce the M1. One boll was hand-picked from each of about 2000 surviving M1 plants, and this bulk was planted at Stoneville, MS in 2009 to produce the M2 and in 2010 to produce the M3 using the same procedure. This was done to reduce the mutation load and increase the level of the additive portion of the genetic variance in the population. In 2011, one boll per plant of the M4 bulk was saved as seed source for the registered material designated as ‘MD 15 M4’. Random samples of the M3 and M4 from the mutant population along with the non-mutated parent were also planted in replicated progeny rows in 2010 and 2011 and tested for fiber length, fiber strength, uniformity, micronaire and seed index. Significantly high sample variances and wider ranges were observed for most of these traits from the mutants as compared to the parent, indicating that mutagenesis created some new valuable variants that breeders, geneticists and other researchers can exploit. Chemical mutagenesis can be used as one of the tools to help overcome the narrow genetic base for some of the economically important traits controlled by few genes in cotton.