Sucrose-Phosphate Synthase, a Biochemical Marker of High Sucrose Accumulation in Sugarcane

• Published in: Crop science 2007-07, Vol.47 (4), p.1530-1539
• Main Authors: Grof, C.P.L, Albertson, P.L, Bursle, J, Perroux, J.M, Bonnett, G.D, Manners, J.M
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; beta-fructofuranosidase; Biological and medical sciences; biomarkers; carbohydrate metabolism; crop yield; Cultivars; Enzymatic activity; enzyme activity; Fundamental and applied biological sciences. Psychology; genetic variation; Genetics; Genetics and breeding of economic plants; genotype; Genotypes; internodes; introgression; Plant breeding; Research methodology; Saccharum officinarum; spatial variation; sucrose; sucrose synthase; sucrose-phosphate synthase; Sugar; Sugarcane
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci2006.12.0825

Increasing sucrose content is a major objective of sugarcane breeding programs. One approach employed by breeders is to introgress new genes from genotypes of Saccharum officinarum L. not previously used in breeding. The activity of a suite of key sucrose metabolizing enzymes was measured in progeny of an introgression program to find biochemical markers associated with high sucrose content, measured as commercial cane sugar (CCS). The enzymes sucrose-phosphate synthase (SPS), three isoforms of invertase, and sucrose synthase were measured in four high and four low CCS clones from an initial cross between a S. officinarum and the commercial cultivar Q165. Subsequently, SPS and the two soluble isoforms of invertase were measured in clones derived from a backcross of one of the progeny to another commercial cultivar Mida. Enzyme activities were measured in tissue from internodes taken from four different positions down the stem profile. Of particular significance was the finding that the activity of a key enzyme involved in sucrose synthesis, SPS, was significantly higher in the upper internodes (one to three) of high CCS clones as compared with low CCS clones in both populations, suggesting that this enzyme may have a key role in establishing metabolic and developmental processes necessary for high sugar accumulation during stem growth and maturation.