A Comparison of Two Boll Sampling Strategies for Fiber Quality Improvement in a Pedigree Scheme

Indeterminate growth in cotton results in a within-plant gradient in boll developmental stages. Distal bolls are set later in the growing season, usually during less than optimal environmental conditions, than other bolls. These differences create variation in fiber quality across bolls within the plant. When breeders make individual plant selections, based on bolls from the center part of the plant or from the whole plant, they might not properly account for the possibly negative contribution of the poorly developed distal bolls. As an alternative approach, breeders can pick only the topmost bolls. If the lint from these distal positions present good fiber characteristics, it is likely that the rest of bolls on the plant will also show good fiber properties. In this work, a population of F2 plants was selected in 2015 based on agronomic performance. For half of them, bolls from every position were picked to represent the most common sampling protocol. For the other half, only top bolls were taken. For both sampling protocol, a selection of F3 seeds from F2 individual plants were planted at Texas Tech University Quaker Farm, Lubbock, in 2016. These lines were stripper harvested, their seedcotton was saw-ginned, and the fiber quality was analyzed. A comparison of the results from both sampling strategies will be reported.