拔节至成熟期遮荫对小麦籽粒高分子量麦谷蛋白亚基积累及GMP含量的影响

 【目的】高分子量麦谷蛋白亚基（HMW-GS）和麦谷蛋白大聚合体（GMP）含量是反映小麦籽粒品质的重要性状,本试验研究拔节到成熟期遮荫对2个含相同HMW-GS亚基类型（7+8、2+12）小麦品种胚乳HMW-GS积累动态和GMP含量的影响。【方法】采用SDS-PAGE电泳和切胶比色的方法,对遮荫条件下小麦籽粒中HMW-GS亚基进行定量分析。【结果】遮荫使HMW-GS的起始形成时间提早,18%和25%重度遮荫处理缩短各亚基和总亚基快速积累期,并降低灌浆后期积累速度,成熟期单粒总HMW-GS积累量低于对照,但成熟期籽粒HMW-GS和GMP含量高于对照。轻度遮荫（10%）延长了籽粒HMW-GS快速积累期,亚基积累量和含量均高于对照。【结论】遮荫处理影响小麦籽粒HMW-GS积累,但其效应与遮荫强度有关。

Effects of Shading From Jointing Stage to Maturity Stage on High Molecular Weight Glutenin Subunits Accumulation and Glutenin Macropolymer Content in Wheat Grain

【Objective】 Accumulations of high molecular weight glutenin subunits (HMW-GS) and glutenin macropolymer (GMP) play key roles in determining grain quality in wheat (Triticum aestivum L.). Two wheat cultivars owning the same HMW-GS type (7+8 and 2+12) were selected to study the effects of shading from jointing to maturity on HMW-GS accumulation and GMP content in grain. 【Method】 HMW-GS was firstly separated using the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and each HMW-GS subunit band in the gel was cut and extracted. Content of each HMW-GS subunit was then quantified by colorimetric analysis of the HMW-GS subunit extraction. 【Result】 Shading from jointing and maturity promoted the initial formation time of HMW-GS. The severe shading treatments (18% and 25%) shortened the rapid accumulation period of HMW-GS and reduced the accumulating rate of total HMW-GS during late grain filling period. Thus, the accumulation amount of total HMW-GS at maturity was lower under these treatments than the non-shading treatment. However, contents of HMW-GS and GMP were higher under severe shading than the control. A low-degree shading treatment (10%) prolonged the rapid accumulation period of HMW-GS, and increased the final accumulation amount and content of total HMW-GSP. 【Conclusion】 Shading from jointing to maturity obviously affected the accumulation amounts and contents of total HMW-GS in wheat grain. However, this regulatory effect was related to shading intensity.