Mohi-Ud-Din Mohammed, Hossain Md Alamgir, Rohman Md Motiar, Uddin Md Nesar, Haque Md Sabibul, Ahmed Jalal Uddin, Hossain Akbar, Hassan Mohamed M, Mostofa Mohammad Golam
Department of Crop Botany, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh.
Department of Crop Botany, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh.
Plants (Basel). 2021 Apr 27;10(5):879. doi: 10.3390/plants10050879.
Drought is one of the foremost environmental stresses that can severely limit crop growth and productivity by disrupting various physiological processes. In this study, the drought tolerance potential of 127 diverse bread wheat genotypes was evaluated by imposing polyethylene glycol (PEG)-induced drought followed by multivariate analysis of several growth-related attributes. Results showed significant variations in the mean values of different morpho-physiological traits due to PEG-induced drought effects. Correlation analysis revealed that most of the studied traits were significantly correlated among them. The robust hierarchical co-clustering indicated that all the genotypes were clustered into four major groups, with cluster 4 (26 genotypes) being, in general, drought-tolerant followed by cluster 1 (19 genotypes) whereas, cluster 2 (55 genotypes) and 3 (27 genotypes) being drought-sensitive. Linear discriminant analysis (LDA) confirmed that around 90% of the genotypes were correctly assigned to clusters. Squared distance () analysis indicated that the clusters differed significantly from each other. Principal component analysis (PCA) and genotype by trait biplot analysis showed that the first three components accounted for 71.6% of the total variation, with principal component (PC) 1 accounting for 35.4%, PC2 for 24.6% and PC3 for 11.6% of the total variation. Both PCA and LDA revealed that dry weights, tissue water content, cell membrane stability, leaf relative water content, root-shoot weight ratio and seedling vigor index played the most important discriminatory roles in explaining drought tolerance variations among 127 wheat genotypes. Our results conclude that the drought-tolerant and -sensitive wheat genotypes identified in this study would offer valuable genetic tools for further improvement of wheat productivity in arid and semi-arid regions during this time of unpredictable climate change.
干旱是最主要的环境胁迫之一，它能够通过扰乱各种生理过程，严重限制作物生长和生产力。在本研究中，通过施加聚乙二醇（PEG）诱导的干旱，随后对几个与生长相关的属性进行多变量分析，评估了127种不同面包小麦基因型的耐旱潜力。结果表明，由于PEG诱导的干旱效应，不同形态生理性状的平均值存在显著差异。相关性分析表明，大多数研究性状之间存在显著相关性。稳健的层次共聚类表明，所有基因型被聚类为四个主要组，一般来说，第4组（26个基因型）耐旱，其次是第1组（19个基因型），而第2组（55个基因型）和第3组（27个基因型）对干旱敏感。线性判别分析（LDA）证实，约90%的基因型被正确分配到各个组。平方距离（）分析表明，各组之间存在显著差异。主成分分析（PCA）和基因型与性状双标图分析表明，前三个成分占总变异的71.6%，其中主成分（PC）1占总变异的35.4%，PC2占24.6%，PC3占11.6%。PCA和LDA均表明，干重、组织含水量、细胞膜稳定性、叶片相对含水量、根冠比和幼苗活力指数在解释127个小麦基因型之间的耐旱性差异方面发挥了最重要的判别作用。我们的结果表明，本研究中鉴定出的耐旱和干旱敏感小麦基因型，将为在当前不可预测的气候变化时期进一步提高干旱和半干旱地区小麦生产力提供有价值的遗传工具。
