Abstract
To assess the relative importance of morphological and biochemical factors in the regulation of sucrose (Suc) accumulation in the sugarcane (Saccharum spp. hybrids) stem, we investigated morphological and biochemical correlates of Suc accumulation among parents and progeny of a family segregating for differences. In contrast to the parents, no relationship was observed between morphology and the level of Suc accumulation among the progeny. The level and timing of Suc accumulation in the whole stalk and within individual internodes was correlated with the down-regulation of soluble acid invertase (SAI) activity. High SAI activity prevented most, but not all, Suc accumulation. There was a critical threshold of SAI activity above which high concentrations of Suc did not accumulate. This low level of SAI activity was always exceeded in the internodes of the lower-Suc-storing genotypes. However, low activity of SAI was not sufficient by itself to account for the Suc accumulation in the higher-Suc-storing genotypes. Major differences in Suc accumulation among the population were attributed to the difference between activities of SAI and Suc phosphate synthase, provided SAI is below the critical threshold concentration. This result is not unexpected, since the pathway of Suc transport for storage involves Suc hydrolysis and resynthesis.
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Selected References
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- Hatch M. D. Sugar accumulation by sugar-cane storage tissue: the role of sucrose phosphate. Biochem J. 1964 Dec;93(3):521–526. doi: 10.1042/bj0930521. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hubbard N. L., Huber S. C., Pharr D. M. Sucrose Phosphate Synthase and Acid Invertase as Determinants of Sucrose Concentration in Developing Muskmelon (Cucumis melo L.) Fruits. Plant Physiol. 1989 Dec;91(4):1527–1534. doi: 10.1104/pp.91.4.1527. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sacher J. A., Hatch M. D., Glasziou K. T. Sugar Accumulation Cycle in Sugar Cane. III. Physical & Metabolic Aspects of Cycle in Immature Storage Tissues. Plant Physiol. 1963 May;38(3):348–354. doi: 10.1104/pp.38.3.348. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sonnewald U., Brauer M., von Schaewen A., Stitt M., Willmitzer L. Transgenic tobacco plants expressing yeast-derived invertase in either the cytosol, vacuole or apoplast: a powerful tool for studying sucrose metabolism and sink/source interactions. Plant J. 1991 Jul;1(1):95–106. doi: 10.1111/j.1365-313x.1991.00095.x. [DOI] [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]
- Welbaum G. E., Meinzer F. C. Compartmentation of solutes and water in developing sugarcane stalk tissue. Plant Physiol. 1990 Jul;93(3):1147–1153. doi: 10.1104/pp.93.3.1147. [DOI] [PMC free article] [PubMed] [Google Scholar]