Carbohydrate Metabolism and Gene Regulation during Anther Development Disturbed by Chemical Hybridizing Agent in Wheat

Abstract

ABSTRACTInduction of male sterility by chemical‐hybridizing agents is important in heterosis breeding, especially for self‐pollinated crops like wheat (Triticum aestivum L.). This study was designed to investigate the association of carbohydrate metabolism with chemical‐induced male sterility (CIMS) in wheat anthers. Transverse section observation showed that during the young microspore (YM) stage, the tapetum of fertile line anthers began to degenerate, while the CIMS line tapetum showed delayed degradation. The levels of nonreducing sugars in the CIMS line anthers always remained higher than in the fertile line, and the starch content of the CIMS line anthers was approximately 45% of those from the fertile line. Compared with the fertile line, the activities of cell wall bound invertase (CWIN) and vacuolar invertase (VIN) were significantly reduced. Quantitative real‐time polymerase chain reaction (qRT‐PCR) analyses showed that the expression levels of one CWIN gene (IVR1) and one VIN gene (IVR5) were significantly downregulated at the YM stage and the vacuolate microspore (VM) stage, and one sucrose transporter gene (TaSUT1) expression was decreased at the YM stage in CIMS anther. The results of the present work imply that sugar transport disruption is a possible crucial cause for CIMS.