Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China.
Food Chem. 2013 Dec 1;141(3):2743-50. doi: 10.1016/j.foodchem.2013.05.101. Epub 2013 May 31.
Grain phytochemical profiles were compared in Tibetan wild barley XZ5 (drought-tolerant), XZ16 (salinity/aluminum-tolerant) and cv CM72 (salinity-tolerant) in response to drought and salinity alone and combination (D+S) during anthesis. Total antioxidant capacity assessed by determining ferric-reducing antioxidant potential (FRAP) in grains increased significantly as follows: D+S>drought>salinity, and XZ5>XZ16>CM72. A marked increase in the total phenol (TP) from individual and combined stresses was observed in XZ5, while a decrease occurred in CM72. Moreover, the activity of α-/β-amylase in the grains under combined stress was 81.8%/16.9% in XZ5 and 48.6%/18.7% in XZ16 higher than that of CM72. Increases in amino acids, protein content and protein fractions of albumin, globulin, hordein and glutelin were maximised under D+S, with larger values in the Tibetan wild genotypes. Observation with a scanning electron microscopy showed a distinct genotypic difference under D+S; for example, XZ5 and XZ16 maintained a relatively integral starch granule with a greater protein deposit/matrix, while CM72 degraded by pitting. This research expands our understanding of barley drought and salt-tolerance mechanisms and provides possibility of Tibetan wild barley in developing barley cultivars with both tolerance to drought and salinity.
在抽穗期，比较了西藏野生青稞 XZ5（耐旱）、XZ16（耐盐/铝）和 cv CM72（耐盐）在单独和组合（D+S）干旱和盐胁迫下的谷物植物化学特征。通过测定谷物中铁还原抗氧化能力（FRAP）来评估总抗氧化能力，结果表明：D+S>D>盐，XZ5>XZ16>CM72。在 XZ5 中，单独和组合胁迫下总酚（TP）明显增加，而 CM72 则减少。此外，在组合胁迫下，XZ5 中α-/β-淀粉酶的活性分别为 81.8%/16.9%，XZ16 为 48.6%/18.7%，均高于 CM72。在 D+S 下，XZ5 和 XZ16 的氨基酸、蛋白质含量以及白蛋白、球蛋白、麦醇溶蛋白和谷蛋白的蛋白质分数增加最大，西藏野生基因型的数值更大。扫描电子显微镜观察表明，在 D+S 下存在明显的基因型差异；例如，XZ5 和 XZ16 保持相对完整的淀粉颗粒，具有更大的蛋白质沉积/基质，而 CM72 则发生凹陷降解。这项研究扩展了我们对大麦耐旱和耐盐机制的理解，并为开发兼具耐旱和耐盐性的大麦品种提供了可能。
