High Temperature-induced Changes in High Molecular Weight Glutenin Subunits of Chinese Winter Wheat and its Influences on the Texture of Chinese Noodles

Post-anthesis temperature affects wheat flour quality, dough properties and end-use quality. In order to investigate the changes in high molecular weight glutenin subunit (HMW-GS) expression caused by elevated temperature and its influences on the texture properties of Chinese noodles, three temperature-induced (<35 °C) treatments were applied to two cultivars with different gluten strengths. The cultivars were grown outside in 0.75 m 2 containers on the farm of Shandong Agricultural University in 2003-2004. Three post-anthesis temperature treatments, at 15 days after anthesis (DAA), 20 and 25 DAA, respectively, were applied during the grain-filling period by moving the containers from outside into a greenhouse at three replicates per treatment. At maturity, the HMW-GS was extracted. The results indicated that the HMW-GS expression from the wheat with stronger gluten strength appeared to be more tolerant under the different treatments than did that from the weaker dough strength wheat. The same HMW-GS (5 + 10) from different cultivars showed different effects on noodle quality. Moderately high temperature treatments benefited wet noodle texture quality and noodle scores at a different degree. All HMW-GS expression in wheat with the weaker strength appeared to be negatively correlated with wet noodle firmness (WNF) and wet noodle cutting force (WNCF). Some correlation coefficients showed significance. However, HMW-GS expression at Glu-Bl and individual Glu-B1x14 expression from the strong wheat demonstrated significantly positive correlations with WNF and WNCF. Individual HMW-GS expression of the Glu-Bl and Glu-Bl location and the X-type subunits showed significantly positive correlations with the noodle score. The same HMW-GS at Glu-Dl from varieties with different gluten strength had different contributions to noodle quality.