College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China.
Department of Botany, Hazara University, Mansehra 21120, Pakistan.
Genes (Basel). 2022 Nov 30;13(12):2261. doi: 10.3390/genes13122261.
Water availability is considered as the main limiting factor of wheat growth illuminating the need of cultivars best adapted to drought situations for better wheat production and yield. Among these, the stay-green trait is thought to be related to the ability of wheat plants to maintain photosynthesis and CO assimilation, and a detailed molecular understanding of this trait may help in the selection of high-yielding, drought-tolerant wheats. The current study, therefore, evaluated the physiological responses of the selected wheat genotypes under pot-induced water stress conditions through different field capacities. The study also focused on exploring the molecular mechanisms involved in drought tolerance conferred due to the stay-green trait by studying the expression pattern of the selected PSI-associated light-harvesting complex I (LHC1) and PSII-associated LHCII gene families related to pigment-binding proteins. The results revealed that the studied traits, including relative water content, membrane stability index and chlorophyll, were variably and negatively affected, while the proline content was positively enhanced in the studied wheats under water stress treatments. Molecular diagnosis of the selected wheat genotypes using the expression profile of 06 genes, viz. , , , , and that encodes for the LHCI and LHCII proteins, indicated variable responses to different levels of drought stress. The results obtained showed the relation between the genotypes and the severity of the drought stress condition. Among the studied genotypes, Chirya-1 and SD-28 performed well with a higher level of gene expression under drought stress conditions and may be used in genetic crosses to enrich the genetic background of common wheat against drought stress.
水资源的可获得性被认为是小麦生长的主要限制因素，这表明需要培育最适应干旱情况的品种，以提高小麦的产量和产量。其中，持绿特性被认为与小麦植株维持光合作用和 CO2 同化的能力有关，对该特性的详细分子理解可能有助于选择高产、耐旱的小麦。因此，本研究通过不同田间持水量评估了选定小麦基因型在盆栽诱导水分胁迫条件下的生理响应。本研究还重点探讨了由于持绿特性赋予的耐旱性的分子机制，研究了与色素结合蛋白相关的 PSI 相关光捕获复合物 I（LHC1）和 PSII 相关 LHCII 基因家族的表达模式。结果表明，在所研究的性状中，包括相对水含量、膜稳定性指数和叶绿素，在水分胁迫处理下，这些性状均受到不同程度的负面影响，而脯氨酸含量则呈正增强。使用编码 LHCI 和 LHCII 蛋白的 06 个基因（即、、、、、和）的表达谱对选定小麦基因型进行分子诊断，表明对不同水平的干旱胁迫有不同的反应。所得结果显示了基因型与干旱胁迫程度之间的关系。在所研究的基因型中，Chirya-1 和 SD-28 在干旱胁迫条件下表现良好，基因表达水平较高，可用于遗传杂交，以丰富普通小麦对干旱胁迫的遗传背景。
