Cotton lint yields have increased dramatically during this century. Much of this increase is attributable to breeding efforts in which nearly the sole selection criterion was :he yield of lint. Future environmental and economic factors will emphasize the need for genetic screening methods more innovative and efficient than selecting for yield alone. This study was conceived and conducted to ascertain a better understanding of physiological and morphological characteristics that contribute to known lint yield differences among cultivars.

Six cultivars each from the Deltapine and Stoneville backgrounds were selected to represent years of release from 1905 to the present. Throughout the 1982 growing season, row sections were sampled to estimate various growth parameters, including both vegetative and reproductive plant parts. In addition, the number of flowers was recorded weekly during July and August.