Lipid remodeling enhances heat tolerance in rose via α-linolenic acid and jasmonate accumulation

The rose, often referred to as the queen of flowers, is one of the four primary cut flowers; however, its growth is susceptible to high-temperature stress. Furthermore, with the advent of global warming, extreme high temperatures are becoming increasingly frequent, presenting significant challenges to the normal growth of roses. High temperatures have emerged as a limiting factor in rose cultivation. In this study, transcriptomics combined with lipid determination was employed to reveal that high temperatures resulted in a significant enrichment of genes within the α-linolenic acid metabolic pathway. Subsequent lipid determination analyses indicated that, following high-temperature treatment of the rose variety 'Hi-Ohgi', the content of α-linolenic acid increased, while there was a notable decrease in the content of the chloroplast lipid components monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), alongside an increase in jasmonic acid content. In comparison to the heat-susceptible variety 'Scarlet Bonica', the heat-resistant rose variety 'Hi-Ohgi' exhibited lower levels of MGDG and DGDG, but higher levels of α-linolenic acid and jasmonic acid, with this trend becoming more pronounced under high-temperature conditions. Additionally, pretreatment of suspension cells from 'Scarlet Bonica' with α-linolenic acid or jasmonic acid significantly inhibited the burst of reactive oxygen species induced by high temperatures. This suggests that roses enhance the production of α-linolenic acid and jasmonic acid through lipid remodeling as a response to high-temperature stress. This research provides a theoretical foundation and precise targets for the cultivation of heat-resistant rose varieties.