Characterizations of a distributional parameter that evaluates contents of immature fibers within and among cotton samples

Thickness of the cotton fiber wall or fiber maturity is an important property affecting fiber quality, yield, and textile performance. Due to the complexity of within-sample variation, mean values alone are not sufficient to evaluate cotton maturity. Distributional parameters should be examined for accurately evaluating cotton maturity variations within a sample. However, maturity distributions have not been well characterized due to difficulties of determining maturity from individual fibers with lengthy and laborious microscopic techniques. Cottonscope was developed recently as an alternative for efficiently measuring fiber maturity by analyzing 20,000 snippets from a cotton sample. Thus, we investigated if Cottonscope enabled assessing maturity distributions as accurately as the microscopic method. Maturity distributions determined by Cottonscope were closer to normal distribution curves as compared with those determined by a microscopic method. By comparing maturity with chemical compositions of developing fibers at various stages, a new maturity threshold of the severely immature fibers was selected. Using this threshold, a distributional parameter, immature fiber content (IFC) was measured by both Cottonscope and microscopic methods from cotton reference materials composed of a broad maturity range. The Cottonscope IFC was strongly and significantly correlated with the IFC measured by the microscopic method. It also enabled distinguishing maturity variations from the cotton samples sharing an identical mean maturity. Therefore, the distributional parameter may be used to improve the ways of evaluating the within-sample maturity variation and detecting differences of fiber maturity distributions among cotton samples. Graphic abstract