Sucrose Metabolism and Accumulation is Disturbed during another Development in the T-Type Cytoplasmic Male Sterility of Wheat (Triticum aestivum)

摘要

T-type cytoplasmic male sterility (T-CMS) plays a significant role in hybrid seed production of wheat. An obstruction ofstarch accumulation in the T-CMS pollen grain insinuated that an anomaly in sugar metabolism might be associated withpollen abortion. To elucidate the relationship between sugar metabolism and T-CMS, levels of sucrose levels and itsdecomposition products, activities of key enzymes and gene expression level involved in its sucrose metabolism atmononucleus stage were investigated. The content of sucrose in T-CMS anthers remained higher than that in the fertile line,but the contents of glucose and fructose in T-CMS anthers were dramatically decreased in contrast with the fertile line. Theactivities of cell wall bound invertase (CWIN), vacuolar invertase (VIN) and neutral invertase (NIN) during sucroseaccumulation in anthers of T-CMS were also decreased to 17.4, 57.8 and 55.9%, respectively. The results of Real-time PCRalso manifested that the expression levels of CWIN gene (IVR1), VIN gene (IVR5) and sucrose transporter gene (TaSUT1)were significantly down regulated in T-CMS anther. It showed that the accumulation of sucrose in T-CMS anthers mightinvolve a decrease in activity and a reduction in content of invertase. It can be concluded that an inability to metabolizeincoming sucrose to hexoses resulted in T-CMS pollen developmental lesion.