副地衣芽孢杆菌对多年生黑麦草非生物胁迫抗性的生理调控机制OA

To investigate the physiological regulation mechanisms of plant growth-promoting bacteria on the drought,cold,and saline-alkali stress tolerance of perennial ryegrass(Lolium perenne L.),this study used Bacillus paralicheniformis(NCBI ID:PRJNA 1402526)as the test strain.A pot inoculation experiment was conducted under three abiotic stress conditions-drought,cold,and saline-alkali stress—to analyze the effects of rhizosphere inoculation on the growth indices,physiological characteristics,and root morphology of perennial ryegrass.The results showed that inoculation with B.paralicheniformis significantly alleviated the growth inhi-bition caused by abiotic stresses.Compared to the non-inoculated control,the inoculated plants exhibited signifi-cantly increased plant height,above-ground and below-ground biomass,along with markedly reduced leaf rela-tive conductivity and malondialdehyde content.Additionally,the activities of superoxide dismutase,peroxi-dase,and catalase,as well as the contents of proline and soluble sugars,were significantly enhanced(P<0.05).Moreover,root system architecture was notably improved.In conclusion,inoculation with B.parali-cheniformis can significantly enhance the resistance of perennial ryegrass to drought,cold,and saline-alkali stresses by synergistically strengthening its antioxidant defense capacity,osmoregulatory function,and root morphological configuration.