The Impact of Variation in Cotton Fiber Maturity on the Estimation of Yield Components.

International spinning mills require bales of cotton fiber with an improved fiber quality profile in order to meet their production goals. Producers depend on breeders to develop cotton varieties with improved yield and fiber quality competitive on international spinning markets. Screening lines based on yield components provides one strategy for accomplishing both of these tasks. While some yield components are measured directly, others are estimated from fiber quality parameters. A set of twelve upland cotton varieties representing a wide range of genetic backgrounds was selected to investigate the potential impact of fiber maturity on yield component estimates. The cultivars were grown in a randomized complete block design with three field replications in Lubbock, Texas during the 2012, 2013 and 2014 growing seasons. Bolls were box picked at harvest in order to provide samples from each variety representing a range of fiber maturity. Fuzzy seed obtained after roller ginning was acid-delinted, scanned on a flatbed scanner, and the WinSeedle Pro software was used to estimate the Seed surface area (SSA). Number of fibers per seed was estimated using fiber quality parameters provided by AFIS (Advanced Fiber Information System). The number of fibers per seed surface area was obtained by dividing the number of fibers per seed and the lint weight, by the estimated SSA. Varieties with relatively stable fiber properties along the plant tend to have less variable number of fibers per seed surface area suggesting that the calculation of the number of fibers per seed surface area may be biased. These results suggests that fiber maturity is important to consider when screening lines based on yield components, as a low fiber maturity will lead to excess fiber breakage during processing and unreliable estimates of fiber density.