Inheritance of fuzz and lint fiber initiation of cotton (Gossypium hirsutum L.)

Abstract

Fibers of cultivated cotton are classified into two types, lint and fuzz. Fuzzless seeds are cotton seeds lacking fuzz on almost the whole surface of the seed except for small amounts of fuzz at the micropylar or chalazal regions. Fuzzless seeds provide a number of advantages such as avoiding delintation processes and increasing the quality of feed rations. Therefore, it is important to develop varieties having seeds without fuzz but with high fiber ratios. This study, in which three different F2 populations have been developed by using three distinct genotypes as parents, was conducted to investigate the quantitative inheritance of fuzz and fiber formation and to generate a genetic mapping population. F2 populations showed 3:1 segregation for fuzz initiation and 15:1 for fiber initiation, meaning that fuzz initiation was controlled by one dominant gene while fiber initiation was controlled by two dominant genes. The ranges were between 2% and 40% for gin turnout, between 0 and 0.04 g for lint index, and between 5.5 and 15.9 g for seed index in the Stoneville 453 × PI 528429 population, while the same characters ranged from 2% to 36%, from 0 to 0.046 g, and from 9.45 to 15.42 g, respectively, for the PI 528429 × Stoneville 453 population. The last F2 population (Fiberless × Stoneville 453) showed segregation values that varied between 0% and 42% for gin turnout, between 0 and 0.045 g for lint index, and between 5.56 and 12.98 g for seed index. Additionally, there was a significant (P < 0.01) and positive correlation between gin turn out and lint index, between seed index and lint index, and between fuzz and gin turn out and lint index. These populations will provide a valuable genetic resource for fiber and fuzz initiation as well as quantitative trait locus mapping experiments.