Producing Quality Cotton by Conventional Breeding, Marker Assisted Selection, and Transgenic Methods

Abstract

New cotton seeds capable of producing fiber with the properties needed by yarn and textile industries in the process of technological advance are needed to maintain market share for Nature's renewable fiber resource. Conventional breeding, marker-assisted selection, and transgenic technologies are possible strategies to achieve improved fiber properties. Breeding has a documented record of improving fiber length and strength to benefit ring yarn manufacture. Open-end yarn manufacturing is supplanting older ring spinning systems and is demanding improved fiber strength, along with finer fiber, and less short and immature fiber. Breeding can achieve these goals, but may be supplemented by marker-assisted selection and transgenic technologies. Marker assisted selection would have particular application to the simultaneous improvement of yield and fiber quality. For modification of fiber traits with narrow sense heritability of 0.5 or higher (0-1.0 scale), marker assisted selection would likely not result in significantly greater gains than phenotypic selection. Efforts to genetically engineer modified cotton fiber properties are underway with data from a few field trials now available. Experience to date suggests that breeding value for a transgenic trait can vary even by the individual plant. Therefore, transgenic breeding may require larger population sizes to allow for simultaneous selection for expression and agronomic traits. Cotton should continue to be the World's primary renewable textile fiber if efforts to improve its fiber properties are continued. [Article copies available for a fee from The Haworth Document Delivery Service: 1-800-342-9678. E-mail address: getinfo@haworthpressinc.com <Website: http://www.haworthpressinc. com>] O. Lloyd May is affiliated with the