Abstract
Assays were conducted to examine the contents of cellulose and callose, and the activities of enzymes related to sucrose
metabolism at various stages of fiber development in colored cottons and white cotton. The results showed that the cellulose
accumulation could be described with Richard curve equations, and the cellulose biosynthesis was reflected by the eigenvalues,
especially the maximum biosynthesis rate (Vmax) and the time taken for cellulose rapid biosynthesis (T). The period from 20
days post anthesis (DPA) to 40 DPA is the key stage for cellulose accumulation in colored cotton. During this period reduced
activity acid invertase (AI) and β-1,3-glucanase, and decreased accumulation and transformation of callose in colored cotton
might limit carbon supply and cellulose accumulation by affecting Vmax and T, thus inhibiting sucrose metabolism during
cellulose biosynthesis, then results in poor fiber quality.
