本土和入侵植物应对水分和营养亏缺的根系性状变异研究OA

The mechanisms by which the root systems of invasive plants respond to nutrient and water deficiency remain poorly understood.In this study,we conducted a paired comparison between Asteraceae invasive plants(Senecio vulgaris,Symphyotrichum subulatum)and native plants(Senecio scandens,Aster ageratoides),examined their root traits,Arbuscular Mycorrhizae Fungi(AMF)colonization rate,and biomass performance under normal and water and nutrient deficient conditions.The results showed that although both water and nutri-ent deficiencies reduced aboveground biomass and AMF colonization rates by more than 20%on average across all species,the invasive plants exhibited significantly greater aboveground biomass and higher AMF coloniza-tion rates compared to native plants.Nutrient deficiency significantly increased specific root length and specific root surface area,promoted root length and surface area of roots with diameters<0.5 mm,and reduced root tissue density in native plants,with average changes ranging from 8.23%to 32.64%in native plants.How-ever,invasive plants showed opposite or no significant changes.With the exception of Symphyotrichum subula-tum,water deficiency enhanced specific root length,specific root surface area,root length and surface area across all diameter classes,while reducing root tissue density in the other species.In summary,the invasive plants demonstrated stronger stress resistance.Under nutrient stress,invasive plants relied more on maintain-ing high AMF colonization,whereas native plants primarily depended on adjustments in root morphology.Under water deficiency,both invasive and native plants exhibited similar root adaptation strategies,but the inva-sive plants maintained higher AMF colonization.Combined stress responses tended to resemble those under single nutrient deficiency.These findings are important for elucidating the mechanisms underlying the adapta-tion of invasive plants to nutrient-and water-deficient environments.