S-腺苷甲硫氨酸缓解盐胁迫对番茄生殖生长的影响OA

Salt stress causes irreversible damage to reproductive development of tomato.To investigate the mitigating effect and mechanism of S-adenosyl-L-methionine(SAM)on tomato reproductive growth under salt stress,this study used'Micro-Tom'tomatoes and conducted experiments through in vitro pollen culture and whole-plant trials.The results showed that salt stress(100 mmol/L NaCl)significantly inhibited pollen viability,germination rate and pollen tube growth,leading to increased flower drop,reduced photosynthesis,decreased antioxidant enzyme activity and lower fruit yield and quality,while the stigma remained insensitive to salt stress.Exogenous application of SAM effectively alleviated these stress-induced effects.Under in vitro conditions,1.0 μmol/L SAM extremely significantly increased the pollen germination rate,pollen tube length,and survival rate by 41.7 percentage points,33.6％and 27.9 percentage points,respectively,and extremely significantly reduced reactive oxygen species(ROS)accumulation by 29.7％.In whole plants,foliar spraying of 0.1 μmol/L SAM extremely significantly reduced salt stress-induced flower drop by 19.1 percentage points,extremely significantly suppressed the expression of salt stress-related genes(S1CIPK4,S1CIPK8)and improved photosynthetic parameters,with net photosynthetic rate,stomatal conductance,transpiration rate,and intercellular CO2 concentration increasing extremely significantly by 22.7％,35.8％,22.5％and 15.5％,respectively.Additionally,it extremely significantly enhanced the activities of peroxidase(POD),superoxide dismutase(SOD)and catalase(CAT)in the anthers by 98.5％,59.7％and 67.4％,respectively.Ultimately,single fruit weight,fruit transverse diameters and longitudinal diameters extremely significantly increased by 33.7％,11.4％and 11.1％,respectively,and fruit coloring time was shortened significantly.In conclusion,SAM effectively alleviates salt stress-induced inhibition of tomato reproductive growth,demonstrating significant potential for improving tomato salt tolerance and ensuring protected cultivation productivity.