Effects Of4Plant Extracts Against Gloeosporium Theae-sinensis Miyaka And Defense Enzymes In Tea Plant

Citrus madurensis peels, Artemisia argyi plant, Cinamomum camphora leaves andPlatycladus orientalis leaves were extracted with acetone. Mycelium growth rate methodsand means of water agar culture were applied to determin the inhibitory effects of theseextracts against mycelium growth and spore germination of Gloeosporium theae-sinesisMiyake, respectively.The protective and curative effects of the4acetone extracts againsttea anthracnose were studied with detached leaves. Colorimetry was used to testPhenylalanine ammonia lyase,Peroxidase and polyphenol oxidase of tea leaves.The resultsare as follows:Among plant extracts those with dosage of1500μg/mL showed the best inhibitoryeffects on mycelium growth and spore germination. Citrus madurensis peels extractshowed the most intensive activity on effects on mycelium growth with an inhibition of93.32%at96h treatment and an EC50value of8.981μ g/mL. The inhibiting rate ofArtemisia argyi plant, Cinamomum camphora leaves and Platycladus orientalis leaves at96h treatment were61.10%,55.64%and48.20%respectively，while EC50value were839.575，1058.682μ g/mL and1429.094μg/mL respectively. Artemisia argyi plant took themost intensive activity on spore germination which had an inhibiting rate of85.54%and anEC50value of281.121μg/mL The inhibiting rate of Citrus madurensis peels, Cinamomumcamphora leaves and Platycladus orientalis leaves were34.85%、55.40%and59.68%respectively，and EC50value were5764.142,1502.49μ g/mL和969.369μg/mL.The protective effects of all plant extracts on detached leaves were better thancurative effects. At the concentration of1500μg/mL，the protective efficacy rates of Citrusmadurensis peels, Artemisia argyi plant, Cinamomum camphora leaves and Platycladusorientalis leaves were62.3%,51.45%,40.25%and36.72%, and correspondingly thecurative efficacy rates of were41.52%,34.92%,31.73and28.42%respectively.The activities of3main defense enzymes such as Phenylalanine aminolyase(PAL),Peroxidase (POD) and PolyPhenol Oxidase (PPO) changed in different degreesafter the treatment of plant extracts with the concentration of1500μg/mL. Effects ofextracts on the activity of POD were better than PAL and PPO.Among extracs Citrusmadurensis peels showed the best effect on the activity of POD.The activites of enzymeswere related with the time after the treatments.The activities of PAL,POD showed atendency:elevate-decline.The activities of PPO showed a tendency:decline-elevate-decline.