Seed priming with brassinolides improves growth and reinforces antioxidative defenses under normal and heat stress conditions in seedlings of Brassica juncea

• 全文链接

油菜素内酯对芥菜幼苗在正常和热胁迫条件下的生长和抗氧化防御有促进作用

关键词：

来源：

Physiologia Plantarum

全文链接：

//agri.nais.net.cn/topic/downloadFile/0dabc424-f7bb-472f-b39d-131788160088

来源地址：

https://onlinelibrary.wiley.com/doi/10.1111/ppl.13814

资源所属：

蔬菜育种专题

类型：

学术文献

语种：

英语

原文发布日期：

2022-11-03

摘要：

Environmental stresses pose a major challenge for plant researchers to fulfill increasing food demand. Researchers are trying to generate high-yielding and stress-tolerant or resistant varieties using classical genetics and modern gene-editing tools; however, both approaches have limitations. Chemical treatments emerged as an alternative to improve yield and impart stress resilience. Brassinosteroids (BRs) are a group of phytohormones that regulate various biological processes, including stress management. With foliar spray methods, BR treatments showed promising results but are not economically feasible. We hypothesize that priming of seeds, which requires lesser amounts of BRs, could be equally effective in promoting growth and stress tolerance. Owing to this notion, we analyzed the impact of priming seeds with selected BRs, namely, 24-epibrassinolide (EBL) and 28-homobrassinolide (HBL), in Brassica juncea under normal and heat shock stress conditions. Seeds primed with BRs and grown until seedlings stage at normal conditions (20℃) were subjected to a heat shock (35℃) for a few hours, relating to what plants experience in natural conditions. Heat shock reduced the growth and biomass with an increased accumulation of reactive oxygen species. As anticipated, BRs treatments significantly improved the growth and physiological parameters with an enhanced antioxidant defense under both conditions. Transcriptional analyses revealed that BRs concomitantly induce growth and oxidative stress-responsive gene expression via the canonical BR-signaling pathway. Transfer of unstressed and heat-shock-treated seedlings to field conditions demonstrated the long-term effectivity of BR-priming. Our results showed seed priming with BRs could improve growth and resilience against heat shock; hence, it appears to be a viable strategy to enhance crop yields and stress tolerance.