火炬树根蘖幼苗对3种草坪草种子萌发和幼苗生长的化感效应OA北大核心CSTPCD

We aimed to clarify the allelopathic effects of Chinese sumac(Rhus typhina)seedlings on common turf species and the underlying mechanisms of such effects.Three common turf species,namely Trifolium repens,Festuca arundinacea,and Lolium perenne,were cultivated in sand,and were treated with aqueous extracts of the root,bark,and leaf of R.typhina tillering seedlings.Seed germination,seedling growth,and physiological traits such as chlorophyll content,root activity,and antioxidant indexes were measured for all of the turf species.Aqueous extracts of the root,bark,and leaf of R.typhina were prepared at three concentrations:12.5,25.0,and 50.0 g·L-1(dry weight/volumewater).A principal component analysis was used to calculate the integrated principal component value(F)based on the allelopathic effects of each extract on each index.These values were then used to assess the comprehensive inhibitory effects of each treatment on each turf species.The results indicated that the allelopathic effects of R.typhina extracts on the turf species were significantly affected by the organ the extract was prepared from,the concentration of the extract,and the type of turf species being treated,and there were significant interactions among these factors(P<0.05).All T.repens seedlings died after being treated with any of the extracts at any concentration.The seed germination and seedling growth of F.arundinacea were significantly inhibited by the root,bark,and leaf extracts of R.typhina.The effect of the root extract did not change as its concentration increased,but the inhibitory effects of bark and leaf extracts increased as their concentrations increased,with the F value decreasing by 1.07-2.77.The leaf and bark extracts of R.typhina had stronger inhibitory effects on F.arundinacea than did the root extract at the same concentration,with F values 0.98-3.23 lower in the leaf and bark extract treatments than in the root extract treatments.The inhibitory effects of R.typhina root and bark extracts on L.perenne first increased and then decreased as their concentrations increased.However,the inhibitory effect of the R.typhina leaf extract continuously increased as its concentration increased,with the F value decreasing by 1.11.In addition,extracts from all organs exhibited greater inhibitory effects on L.perenne than on F.arundinacea,with F values that were 0.64-2.96 lower in L.perenne than in F.arundinacea.Generally,the leaf extracts had stronger inhibitory effects than the root and bark extracts at concentrations of 12.5 and 50.0 g·L-1,with F values that were 0.44-1.55 lower in the leaf extract treatments than in the root and bark extract treatments.However,the bark extract had a stronger inhibitory effect than the leaf and root extracts at a concentration of 25.0 g·L-1,with F values that were 0.51-0.69 lower in the bark extract treatments than in the leaf and root extract treatments.In conclusion,these results show that F.arundinacea is the most suitable of the three tested turf species to be planted under R.typhina,and T.repens should be avoided.