| Camellia oleifera is an important woody oil tree species in china. Colletotrichum gloeosporioides and Myrothecium camelliae are the major diseases in China's Camellia producing areas. They occur broadly and cause serious drop in buds and leaves, sometimes result in the death of the trees. The long-term use of chemical pesticides to control camellia oleifera diseases has made the pathogens cause serious resistance and has seriously polluted the ecological environment.Some pesticides composition have been checked in tea oil and greatly decrease the quality of tea oil. These problems seriously influence the the healthy development of the Camellia oleifera industry.This paper screened a lot of plant extracts with high inhibition effects and made different mixtures with different antibacterial constituents with different mass rates. We initially developed a plant source agent with high prevention and treatment effects against the the major diseases of Camellia oleifera.The main research results are as follows:(1) The inhibition screening of different plant extracts against the the major diseases of Camellia oleifera.Throug h growth inhibitory effects of 40 kinds of plant water extracts, the results indicate that the inhibitory effects of 7 kinds of plant extractions against the main plant Camellia diseases are above 60 %such as clove, scutellaria, aloe. When the concentration is 50mg/mL, the prevention effect of the extracts of clove and scutellaria against the Camellia anthrax is 81.7% and 77.4% in vitro. And the treatment effect, respectively, is 74.9% and 67.7%. The SR value of mixture with different weight rate of clove and scutellaria extracts is bigger than 0.5 but smaller than 1.5.(2) The inhibition effects of effective antimicrobial compound and mixture against the main Camellia diseases.The toxicity regression equation of eugenol, an effective antibacterial ingredient from clove, against Colletotrichum gloecsporioides and Myrothecium camelliae is, respectively, y=2.1265x+1.8475 and y=2.5544x+0.6262, and EC50 is 30.37μg/mL and 51.55μg/mL.The toxicity regression equation of baicalein, an effective antimicrobial component from scutellaria, is, respectively, y= 2.0831x+1.277 and y =2.1506x+l.3492, and EC50 is 61.26μg/mL and 49.83μg/mL. The MIC of mixtures F1, F2, F3 against the anthrax spores is 50μ/ml, the MFC is 75μg/mL. The SR values of mixtures with different weight ratio of eugenol and baicalein against the main Camellia diseases are bigger than 0.5 but less than 1.5. These indicate the inhibition effects have certain addition after mixing the two single antibacterial compound. (3) The development of botanical pesticides against the main Camellia diseases.Through the prevention and treatment effects of different mixture pesticides processed by different solvents against the main Camellia diseases.We find the prevention and treatment effects will be effectively improved when the solvents of mixtures are xylene, Pesticide Emulsifier 600#, NAA. By L9 (34) orthogonal experiment, the results show the optimum formula of mixture pesticide is 10% eugenol,10%baicalein,5%sesamin,67.6%xylene,5.2%Pesticide Emulsifier 6O0#,2.1 % NAA.Throug h testing the stability of mixture pesticides, the results show that when pH is between 6 to 10, temperature at 0-80℃, the prevention effect is 70%, after the light treatment for 5-48h, the prevention effect is also more than 70%. The lasting time of prevention effect of mixture pesticides against the major Camellia diseases is at least 4d. |
PDF Full Text Request