Wheat NILs contrasting in grain size show different expansin expression, carbohydrate and nitrogen metabolism that are correlated with grain yield

Two wheat near-isogenic lines (NILs; -GS (small grain size) and + GS (large grain size)) were obtained by backcrossing. We found that the grain volume and weight of + GS were significantly higher than those of -GS. There was a corresponding increase in grain yield associated with the + GS line. For analysis of causes, we investigated and compared the anatomic and physiological characteristics of two NILs during the grain filling stage. The...