【摘要】 利用人工环境控制室对盆栽冬小麦(品种:‘济南17’和‘鲁麦2 1’) (Triticumaestivumcv .‘Ji′nan17’and‘Lumai2 1’)分别在子粒灌浆前期、中期和后期进行了2 5℃/ 35℃(夜/昼)的高温胁迫处理,以生长在2 0℃/ 30℃(夜/昼)环境中的小麦为对照,研究了灌浆期不同阶段高温胁迫对小麦产量和品质的影响。结果发现:1)子粒蛋白质积累速率在高温处理期间显著提高(p<0 .0 5 ) ,但高值持续期缩短,并最终造成植株氮素积累量减少,氮素收获指数降低(p <0 .0 5 )。2 )小麦蛋白质的组成和品质对不同灌浆阶段的响应存在显著差异,前期高温胁迫导致麦谷蛋白/醇溶蛋白的比值以及麦谷蛋白大聚合体(GMP)含量增加,标志蛋白质和淀粉品质的湿面筋含量升高、沉降值增加、膨胀势和高峰粘度等指标也显著提高;灌浆中期高温却导致上述指标降低;灌浆后期高温在造成粒重减小、产量降低和淀粉品质下降的同时,却有利于蛋白质含量的提高。3)小麦淀粉积累的形成与蛋白质品质的形成是两个既相互联系又相互独立的过程,高温条件下子粒蛋白质含量的升高是淀粉积累量减少造成的。更多还原

【Abstract】 Changes in the yields and quality and the physiological response of winter wheat (Triticum aestivum cv. ’Ji′nan17’ and ’Lumai21’) grown under heat stress during different filling stages were studied. Winter wheat growing in flowerpots was transferred to temperature-controlled open top chambers (OTC) after anthesis. Heat stress treatments of 25 ℃/35 ℃ (night/day) were applied at early filling stage (1-10 days after anthesis), middle filling stage (11-20 days after anthesis), and late filling stage (21-30 days after anthesis). The controls were grown at temperatures of 20 ℃/30 ℃ (night/day). Protein accumulation rate, nitrogen accumulation and distribution, kernel weight and yield, test weight, protein composition, protein content, wet gluten content, glutenin macropolymer (GMP) content, and starch and protein quality traits were measured. The results showed that protein accumulation rate in wheat kernels grown in the 25 ℃/35 ℃ (night/day) chambers were higher than those in the control chambers (p<0.05); however, nitrogen accumulation was reduced and the nitrogen harvest index (NHI) declined under heat stress (p<0.05). There were differences in starch and protein quality responses to heat stress during the different filling stages. Protein and starch quality traits improved at the early filling stage but declined at the middle and late filling stages under heat stress; however, the protein content increased at late filling stage under heat stress. Protein content increased but kernel weight decreased under higher temperatures, which suggested that the starch accumulation rate decreased more sharply than protein accumulation rates under higher temperature. The two varieties, ’Ji’nan17’ and ’Lumai21’, showed similar responses to heat stress at the different filling stages.更多还原