Abstract
Cotton plants (cv. Coker 100) were exposed to a 14-hour dark period. Starch degradation occurred with no accumulation of sugars due mainly to translocation. Considerable amounts of starch degradation products however were detected from leaves after phloem transport was blocked. A minor component (10 to 25% of total starch) with a linear structure, amylose, was preferentially degraded, whereas the major multiple-branched component (about 80%), amylopectin, showed an increasing resistance to degradation with leaf age. This relationship was also shown by the decreasing iodine-binding capacity of unit starch with increasing leaf age. The structural resistance of amylopectin to enzymic dark degradation was one of the barriers to starch dissolution in cotton.
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Selected References
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- Chang C. W. Carbon dioxide and senescence in cotton plants. Plant Physiol. 1975 Mar;55(3):515–519. doi: 10.1104/pp.55.3.515. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chang C. W. Starch and its component ratio in developing cotton leaves. Plant Physiol. 1979 May;63(5):973–977. doi: 10.1104/pp.63.5.973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Murata T., Akazawa T. The role of adenosine diphosphate glucose in leaf starch formation. Biochem Biophys Res Commun. 1964 May 22;16(1):6–11. doi: 10.1016/0006-291x(64)90203-7. [DOI] [PubMed] [Google Scholar]
- Nafziger E. D., Koller H. R. Influence of Leaf Starch Concentration on CO(2) Assimilation in Soybean. Plant Physiol. 1976 Apr;57(4):560–563. doi: 10.1104/pp.57.4.560. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Upmeyer D. J., Koller H. R. Diurnal trends in net photosynthetic rate and carbohydrate levels of soybean leaves. Plant Physiol. 1973 May;51(5):871–874. doi: 10.1104/pp.51.5.871. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Van Handel E. Direct microdetermination of sucrose. Anal Biochem. 1968 Feb;22(2):280–283. doi: 10.1016/0003-2697(68)90317-5. [DOI] [PubMed] [Google Scholar]