Abstract:
Drought is one of the predominant abiotic stresses which have phenomenal impact on crop productivity. Alterations in aquaporin gene expressions are part of complex molecular responses by plant in response to drought. To better understand the role of aquaporins in economically important crop chilli (Capsicum annuum), drought induced gene expression of twelve aquaporins was determined in drought tolerant-KCa-4884 and drought susceptible-G-4 genotypes. Conjointly, the effect of drought on leaf water status and photosynthetic parameters were evaluated. Gene expression of all examined 12 aquaporins was up-regulated in KCa-4884 and in contrast, all the aquaporin genes were down-regulated in G-4 under drought stress. Significant variations among two chilli genotypes have been recorded in photosynthetic rate (P n ), stomatal conductance (G s ), and relative water content (RWC), sub-stomatal CO2 concentration (C i ). KCa-4884 revealed significantly high rates of P n and RWC and decreased G s under water deficit conditions providing evidence for superior drought adaptive strategies. Differences in physiological parameters illustrate prevention of water loss during drought. Up-regulation of aquaporins in drought tolerant genotype implicates their possible role in water relations and photosynthetic performance even under extended drought conditions.
摘要:
干旱是主要的非生物胁迫之一,对作物生产力具有显着影响。水通道蛋白基因表达的改变是植物响应干旱的复杂分子反应的一部分。为了更好地了解水通道蛋白在重要经济作物辣椒(辣椒)中的作用,在耐旱KCa-4884和干旱易感G-4基因型中确定了12种水通道蛋白的干旱诱导基因表达。同时,评价了干旱对叶片水分状况和光合参数的影响。所有检查的12种水通道蛋白的基因表达在KCa-4884中上调,相比之下,在干旱胁迫下,所有水通道蛋白基因在G-4中都下调。两种辣椒基因型之间的显着差异已记录在光合速率(Pn)中,气孔导度(Gs),和相对含水量(RWC),气孔下CO2浓度(Ci)。KCa-4884显示,在缺水条件下,Pn和RWC的比率显着升高,Gs降低,为优越的干旱适应策略提供了证据。生理参数的差异说明了干旱期间水分流失的预防。即使在长期干旱条件下,耐旱基因型中水通道蛋白的上调也暗示了它们在水关系和光合性能中的可能作用。