Intraspecific And Interspecific Allelopathic Effects Among Kentucky Bluegrass And Other Plants

The turf is an important part of the urban ecosystem.Kentucky bluegrass is one of the most important and widely used cold-season turfgrass.Therefore,understanding the relationship between bluegrass and itself and other plants can be important.The allocation of lawns in urban green space provides a certain theoretical basis.This experiment used Bothriochloa ischaemum,Elymus dahuricus,Agropyron cristatum,Melilotus suaveolens,Vicia amoena,Everest,Lucky star,Nuglade,Orychophragmus violaceus,Zinnia elegans and Tagetes patula,with different concentration gradients(0,0.08,0.17,0.34,0.67 g·ml-1)Leaf,rhizome extract,matrix and soil mixture(mass ratio 1:9),and grass mat to study the effects of Kentucky bluegrass on the growth of itself and other plants.The results are as follows:(1)The extracts from different parts of Kentucky bluegrass inhibited the germination rate,germination potential,bud length,root length and fresh weight of the tested plants.As the concentration increased,the inhibitory effect gradually increased,when the concentration reached 0.34 g·ml-1,the seed germination and growth of the tested plants were significantly inhibited at the inhibition was maximized at a concentration of 0.67 g·ml-1,and the germination of the saplings,Everest,Lucky Star and Nuglade,was completely inhibited.The allelopathic effects of the extracts from different parts were different,and the inhibitory effect of the root extract of the bluegrass was greater than that of the leaf extract.The allelochemical coumarin was detected from the bluegrass by high performance liquid chromatography,and the content of allelochemicals in the roots was higher than that in the leaves.(2)Adding leaves and rhizome powder to the soil has an inhibitory effect on the growth of the tested plants.The activities of alkaline phosphatase,sucrase,urease and dehydrogenase in soil decreased,and the plant number,plant height and biomass accumulation of plants decreased,indicating that the allelopathic substances of Kentucky bluegrass entered the soil and affected their own and other plant growth..(3)The grass seed layer of meadow grass has different growth of different tested plants,which promotes the number of plants of the blue orchid,and inhibits the rest of the plants;the fresh and heavy parts of all the tested plants are fresh and dry.The weight is significantly reduced.The grass mat grass layer affects itself and other plants by changing conditions such as moisture and temperature.In summary,in the natural world,the bluegrass in addition to allelopathic effects,through the grass mat to intercept water,change soil temperature and other ways affecting the growth of themselves and other plants.