Transcriptome sequencing revealed the mechanism of promoting floret opening by exogenous methyl jasmonate in sorghum.

Flowering time is a critical trait reflecting the adaptation of plants to their environments. Our initial research has shown that exogenous methyl jasmonate (MeJA) significantly promoted the floret opening of sorghum. To better understand the mechanism of this phenomenon in sorghum, the comparative transcriptome analysis was performed. Transcriptomic analysis showed that the most number of differentially expressed genes was presented between control plants and plants treated with 2.0 mM exogenous MeJA in 2.5 h. A large number of differentially expressed genes were assigned to the subcategory of carbohydrate metabolism and lipid metabolism. The transcriptomic analysis of differentially expressed genes involved in glycolysis/gluconeogenesis and tricarboxylic acid cycle indicated a close relationship between carbohydrates metabolism and flowering. In addition, potassium uptake proteins and aquaporins also played important role in response to the exogenous MeJA in the flowering process. These results provide insights into the effect of MeJA on flowering time and explore the possible molecular mechanism of advancing the flowering period by spraying MeJA. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02743-6.

Effect of exogenous methyl jasmonate treatment on disease resistance of postharvest kiwifruit.

Kiwifruit (Actinidia deliciosa cv. Jinkui) were treated with 0.1 mmol/L methyl jasmonate (MeJA) to investigate the effects on disease resistance to soft rot caused by Botryosphaeria dothidea. The results showed that MeJA treatment significantly reduced the diameter of lesions after inoculation with B. dothidea. This treatment significantly enhanced the activities of related antioxidant protective enzymes, defence-related enzymes including catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), polyphenol oxidase (PPO), chitinase (CHI), ß-1,3 glucanase (GLU) and increased the accumulation of total phenolic content, while the degree of membrane lipid peroxidation was reduced. MeJA treatment effectively enhanced gene expression of AcPOD, AcSOD, AcCHI and AcGLU. The results from this research suggest that MeJA treatment is a promising and safe strategy for controlling postharvest rot soft of kiwifruit.