Changes in Biochemical Components of Naturally Colored Brown Cotton Fiber during Development

Objective:The aim of the study was to research the specialties of biochemical components of naturally colored brown cotton fiber during development,and to analyze the correlation between the pigment synthesization and the development of cotton fiber.The results would contribute to the breeding of naturally colored cotton.Method:4 kinds of naturally colored brown cotton were compared with 1 conventional white cotton Simian-3 to study the respects of reductive sugar,soluble proteins,lipids and cellulose in fiber during entire stages.The dynamic changes regulation of the biochemical components was analyzed.The relationship between the pigment contents and the biochemical components contents was observed.Result:The moisture at 40 days post anthesis(days post anthesis,DPA) and the reductive sugar content at 10 DPA of the natural brown cottons fiber were lower than that of conventional white cotton,but the reductive sugar of natural brown cottons fiber from 30 to 40 DPA were higher than that of the conventional white cotton.In contrast to the soluble proteins peak at 20 DPA,the soluble protein peak of naturally colored brown cotton presented at 25 DPA.The determining of cellulose during fiber development indicated the cellulose contents of conventional white cotton fiber at every stage were higher than that of natural brown cotton.The contents of moisture,reductive sugar,and soluble proteins declined gradually as the fiber development,whereas the cellulose increased continuously.The correlation between the pigment content of the mature fiber and reductive sugar at 10 DPA,the cellulose contents at 30-40 DPA were significant negative at the 0.05 level(2-tailed).The correlation between the pigment content and reductive sugar at 35 DPA was significant positive at 0.01 level(2-tailed),and the cellulose content at 15 DPA were significant negative at the 0.01 level(2-tailed).Conclusion:The biochemical components of naturally colored brown cotton during fiber development stages was obviously different from that of conventional white cotton.However,dynamic changes regulations of the biochemical components of naturally colored brown cotton were consistent with that of the conventional white cotton.The biochemical components of naturally colored brown cotton fiber during development were associated with the pigment synthesization.