Abstract:

Fiber strength is one of crucial properties of fiber quality in cotton, and cellulose accumulation plays an important role in the formation of fiber strength, but there is little physicochemical data to document the relationship between them. In the present experiment, fourteen cotton cultivars with various fiber strength were selected to study the characters of cellulose accumulation and the relationships among them. The dynamic curves of cotton cellulose accumulation were all in accordance with the model of logistic on bolls from different fruiting branches. Based on the logistic model, some eigenvalues were gained. Variability and relativity analyses were made on them. The results showed that these were a wide range of variation for V_max (the maximal speed of cotton cellulose accumulation) and T (the duration of cotton cellulose speed accumulation) and fiber strength had positive correlation with T but negative correlation with V_max. The cluster analysis results based on cotton fiber cellulose accumulating parameters (T and V_m) and fiber strength by the SPSS software showed that, in the same Euclidean distance, there were differences among bolls on the three fruiting branches. As a whole, the fourteen cultivars could be grouped into three types by two criteria. Based on the cotton cellulose accumulation velocity, they could be clustered into rapid, gentler and medium groups, and based on the fiber strength, they could be clustered into lower, high and medium groups, and DSC-1, KC-1 and AC-33B were their representational cultivars respectively. The results also indicated that, there were differences among genotypes in cellulose accumulation characters and cotton fiber strength, and tight relationship between cotton cellulose accumulation and cotton fiber strength, the gentler speed cellulose accumulation in secondary thickening of fiber cell wall is in favor of forming high fiber strength.

Key words: Cotton, Cellulose accumulation, Genotypic difference, Fiber strength