Kumar Ranjeet R, Goswami Suneha, Shamim Mohammed, Mishra Upama, Jain Monika, Singh Khushboo, Singh Jyoti P, Dubey Kavita, Singh Shweta, Rai Gyanendra K, Singh Gyanendra P, Pathak Himanshu, Chinnusamy Viswanathan, Praveen Shelly
Division of Biochemistry, Indian Agricultural Research InstituteNew Delhi, India.
Department of Molecular Biology and Genetic Engineering, Bihar Agricultural UniversityBhagalpur, India.
Front Plant Sci. 2017 Sep 20;8:1603. doi: 10.3389/fpls.2017.01603. eCollection 2017.
Wheat is highly prone to terminal heat stress (HS) under late-sown conditions. Delayed- sowing is one of the preferred methods to screen the genotypes for thermotolerance under open field conditions. We investigated the effect of terminal HS on the thermotolerance of four popular genotypes of wheat i.e. WR544, HD2967, HD2932, and HD2285 under field condition. We observed significant variations in the biochemical parameters like protein content, antioxidant activity, proline and total reducing sugar content in leaf, stem, and spike under normal (26 ± 2°C) and terminal HS (36 ± 2°C) conditions. Maximum protein, sugars and proline was observed in HD2967, as compared to other cultivars under terminal HS. Wheat cv. HD2967 showed more adaptability to the terminal HS. Differential protein-profiling in leaves, stem and spike of HD2967 under normal (26 ± 2°C) and terminal HS (36 ± 2°C) showed expression of some unique protein spots. MALDI-TOF/MS analysis showed the DEPs as RuBisCO (Rub), RuBisCO activase (Rca), oxygen evolving enhancer protein (OEEP), hypothetical proteins, etc. Expression analysis of genes associated with photosynthesis ( and ) and starch biosynthesis pathway ( and ) showed significant variations in the expression under terminal HS. HD2967 showed better performance, as compared to other cultivars under terminal HS. SSS activity observed in HD2967 showed more stability under terminal HS, as compared with other cultivars. Triggering of different biochemical parameters in response to terminal HS was observed to modulate the plasticity of carbon assimilatory pathway. The identified DEPs will enrich the proteomic resources of wheat and will provide a potential biochemical marker for screening wheat germplasm for thermotolerance. The model hypothesized will help the researchers to work in a more focused way to develop terminal heat tolerant wheat without compromising with the quality and quantity of grains.
在晚播条件下，小麦极易遭受后期热胁迫（HS）。延迟播种是在田间条件下筛选耐热基因型的首选方法之一。我们研究了后期热胁迫对四种常见小麦基因型即WR544、HD2967、HD2932和HD2285在田间条件下耐热性的影响。我们观察到在正常（26±2°C）和后期热胁迫（36±2°C）条件下，叶片、茎和穗中的蛋白质含量、抗氧化活性、脯氨酸和总还原糖含量等生化参数存在显著差异。与后期热胁迫下的其他品种相比，HD2967中观察到的蛋白质、糖和脯氨酸含量最高。小麦品种HD2967对后期热胁迫表现出更强的适应性。HD2967在正常（26±2°C）和后期热胁迫（36±2°C）条件下叶片、茎和穗的差异蛋白质谱分析显示了一些独特蛋白质斑点的表达。基质辅助激光解吸电离飞行时间质谱（MALDI-TOF/MS）分析表明差异表达蛋白（DEPs）为核酮糖-1,5-二磷酸羧化酶/加氧酶（Rubisco，简称Rub）、Rubisco活化酶（Rca）、放氧增强蛋白（OEEP）、假定蛋白等。与光合作用相关基因（和）以及淀粉生物合成途径相关基因（和）的表达分析表明，在后期热胁迫下表达存在显著差异。与后期热胁迫下的其他品种相比，HD2967表现出更好的性能。与其他品种相比，HD2967中观察到的淀粉合酶（SSS）活性在后期热胁迫下表现出更高的稳定性。观察到响应后期热胁迫触发的不同生化参数调节了碳同化途径的可塑性。鉴定出的差异表达蛋白将丰富小麦的蛋白质组资源，并为筛选耐热性小麦种质提供潜在的生化标记。假设的模型将帮助研究人员更有针对性地开展工作，培育出后期耐热的小麦，同时不影响籽粒的品质和产量。
