Division of Biochemistry, Indian Agricultural Research Institute, Pusa Campus, New Delhi 110012, India.
Division of Plant Physiology, Indian Agricultural Research Institute, Pusa Campus, New Delhi 110012, India.
Ecotoxicol Environ Saf. 2019 Jun 15;174:637-648. doi: 10.1016/j.ecoenv.2019.03.020. Epub 2019 Mar 12.
Gamma irradiation has been reported to modulate the biochemical and molecular parameters associated with the tolerance of plant species under biotic/ abiotic stress. Wheat is highly sensitive to heat stress (HS), as evident from the decrease in the quantity and quality of the total grains. Here, we studied the effect of pre-treatment of wheat dry seeds with different doses of gamma irradiation (0.20, 0.25 and 0.30 kGy) on tolerance level and quality of developing wheat endospermic tissue under HS (38 °C, 1 h; continuously for three days). Expression analysis of genes associated with defence and starch metabolism in developing grains showed maximum transcripts of HSP17 (in response to 0.25 kGy + HS) and AGPase (under 0.30 kGy), as compared to control. Gamma irradiation was observed to balance the accumulation of HO by enhancing the activities of SOD and GPx in both the cvs. under HS. Gamma irradiation was observed to stabilize the synthesis of starch and amylose by regulating the activities of AGPase, SSS and α-amylase under HS. The appearance of isoforms of gliadins (α, β, γ, ω) were observed more in gamma irradiated seeds (0.20 kGy), as compared to control. Gamma irradiation (0.25 kGy in HD3118 & 0.20 kGy in HD3086) was observed to have positive effect on the width, length and test seed weight of the grains under HS. The information generated in present investigation provides easy, cheap and user-friendly technology to mitigate the effect of terminal HS on the grain-development process of wheat along with development of robust seeds with high nutrient density.
伽马辐照已被报道可调节与生物/非生物胁迫下植物物种耐受相关的生化和分子参数。小麦对热胁迫（HS）非常敏感，这表现在总谷物数量和质量的下降。在这里，我们研究了用不同剂量的伽马辐照（0.20、0.25 和 0.30 kGy）预处理小麦干种子对 HS（38°C，1 h；连续三天）下发育的小麦胚乳组织的耐受性和质量的影响。对发育中的谷物中与防御和淀粉代谢相关的基因进行表达分析表明，与对照相比，HSP17（对 0.25 kGy + HS 有反应）和 AGPase（在 0.30 kGy 下）的转录物最多。辐照被观察到通过增强 SOD 和 GPx 在两种品系中的活性来平衡 HO 的积累，从而减轻 HS 下的活性氧的积累。辐照被观察到通过调节 AGPase、SSS 和α-淀粉酶的活性来稳定淀粉和直链淀粉的合成，从而稳定 HS 下的淀粉和直链淀粉的合成。与对照相比，在辐照种子（0.20 kGy）中观察到麦醇溶蛋白（α、β、γ、ω）的同工型出现更多。在 HS 下，辐照（HD3118 中的 0.25 kGy 和 HD3086 中的 0.20 kGy）被观察到对谷物的宽度、长度和测试种子重量有积极影响。本研究提供的信息提供了一种简单、廉价和用户友好的技术，可减轻终端 HS 对小麦谷物发育过程的影响，同时开发具有高营养密度的强壮种子。
