关键词: 甘蔗, 健康种苗, 单糖转运蛋白基因, 基因表达, 产量

Abstract: The sugarcane yield can be increased by planting disease-free sugarcane seedlings. However, the physiological and molecular mechanisms of this yield increasing are still not clear now. Monosaccharide transporters are one type of key regulatory proteins involved in carbon accumulation and partitioning processes, and play an important role in plants defense process. The differential expression of three monosaccharide transporter genes(SGT1, SGT2 and PST2a)in disease-free and untreated sugarcane plants was studied to clarify the potential function of these genes on sugarcane yields. The expression levels of SGT1, SGT2 and PST2a in leaves of disease-free plants at seedling and tillering stages were obviously higher than untreated plants. Furthermore, the expression levels of these genes were increased in immature internodes of disease-free plants at elongation and mature stages, but there were no difference in mature internodes. The sugarcane leaves(at seedling and tillering stages)and the immature internodes(at elongation and mature stages)grow rapidly and demand for more monosaccharide to provide energy and the precursor of biosynthesis. The up-regulations of these monosaccharide transporter genes might accelerate the growth and biomass accumulation of disease-free sugarcane plants by increasing the transporting and uptake of monosaccharide.

Key words: sugarcane, disease-free plants, monosaccharide transporter gene, gene expression, yield