Relationship of Seed/Boll to Other Yield Components and Fiber Quality of Pima Cotton1

Abstract The relationship of number of seed/boll to other yield components and fiber quality of two cultivars of Pima cotton (Gossypium barbadense L.) was investigated as part of a study of the effects of environment on the variability of these cultivars in three tests. A fourth test had only one cultivar. Bolls examined contained from 1 to 31 seed. Environment of the four tests strongly influenced the proportion of bolls in the different seed number classes. Plants grown under favorable production conditions, such as lower summer temperatures, productive soil, and a wet irigation regime, produced a higher percentage of large bolls (more seed) than those grown less favorable environments. Cultivars did not differ in seed/boll. An increase in the number of seed/boll was associated with the following: decreased mean seed wt, increased lint wt/seed, decreased fiber length and uniformity, and increased micronaire, but strength was unaffected. The unexpected increase in lint wt/seed with a decrease in seed size can be explained by the observed concomitant increase in fiber coarseness.