Relationship of over-expression of high molecular weight glutenin subunit Bx7 with gluten strength.

摘要

A collection of bread wheat cultivars released over the last quarter of a century, as well as a number of experimental lines, were characterised for the presence of Glu-Bl encoded high molecular weight (HMW) glutenin subunits Bx7 and Bx7*, and the amount of protein present in SDS-PAGE electrophoretic separations of each subunit determined by densitometry. In agreement with previous studies, the amount of protein present was variable in the case of subunit Bx7, with some genotypes showing relatively low amount compared to the other HMW glutenin subunits present, and other genotypes showing relatively high amount. No evidence of over-expression of subunit Bx7* was found . Characterising the genotypes for the remaining HMW subunits and evaluating theirgluten strength by the SDS-sedimentation test, it appeared that the presence of an over-expressed subunit Bx7 in a genotype tended to increase its gluten strength. Furthermore, over-expression of Bx7 compensated to a certain extent for the deleterious effect on gluten strength associated with the presence of secalins encoded by Gli-Rl carried by the translocated chromosome 1BL.1RS.