| Alfalfa(Medicago sativa)is the most widely planted perennial leguminous forage in my country and the world.The soil-borne pathogen Fusarium oxysporum is one of the important restrictive factors in the production of alfalfa,which seriously affects the yield and quality of grass.In order to clarify the effect of F.oxysporum.on the growth and nutritional quality of alfalfa,this thesis studied the changes in plant height,regeneration rate,crude protein and crude fat content of 20 representative alfalfa varieties at home and abroad after inoculation with F.oxysporum.through field experiments.The main findings are as follows:(1)The growth rate of different species decreased significantly after inoculation with F.oxysporum.The plant height and regeneration rate of 20 alfalfa varieties were significantly reduced after inoculation with F.oxysporum.(P <0.05),the plant height reduction range was 16.7%-64.2%,and the regeneration rate reduction range was14.3%-63.8%.Among them,the plant height reduction rate and regeneration rate reduction rate of "Zhonglan No.2","040" and "WL168HQ" are all greater than 60%;the plant height reduction rate and regeneration rate of "3010","WL366HQ" and "Normal" The reduction rate is less than 20%.(2)The nutritional quality of different species was significantly reduced after inoculation with F.oxysporum.The crude protein and crude fat content of 20 alfalfa varieties were significantly reduced after inoculation with F.oxysporum.(P <0.05),the crude protein content decreased in the range of 15.2%-65.5%,and the crude fat content decreased in the range of 9.4%-68.4%.Among them,the crude protein content reduction rate and crude fat content reduction rate of "Zhonglan No.2" were both greater than 60%;the crude protein content reduction rate and crude fat content reduction rate of "Normal","3010" and "WL366HQ" were all less than 20%.(3)Comprehensive growth and nutritional quality indicators found that F.oxysporum.is the most harmful to "Zhonglan No.2" and the least harmful to "Normal","WL366HQ" and "3010".Among them,the regeneration rate of "Zhonglan No.2","3010" and "WL366HQ" is significantly positively correlated with plant height,crude protein and crude fat content(P <0.05);"Normal" plant height is significantly positively correlated with regeneration rate(P <0.05),... |
