| The Hengyang area of Hunan has a large area of red loam and purple shale soil suitable for fresh jujube cultivation.In recent years,the fresh jujube in the south has rapidly developed into one of the local high-efficiency fruits,but the subsequent jujube disease has seriously restricted the development of the fresh jujube industry.To this end,the experiment is based on Hengshan County,Hengnan County and Qidong in Hengyang area.Zhanhua winter jujube and mid-autumn crisp jujube of 6 fresh jujube bases were used as test materials.Based on the investigation of the types and pathogenesis of fresh jujube diseases,the pathogen identification of main diseases was carried out,and the growth rate method was used to determine the pathogens.The antibacterial activity of 9 kinds of Chinese medicine acetone extract and 5 kinds of medicines on the pathogen of the shrinking disease of jujube,Alternaria alternata,and the pathogen of the black leaf spot of Jujube leaf,and the antibacterial activities of 5 kinds of agents against Alternaria alternata and Calonectria colhounii were compared,which provided a certain scientific basis for the development of plant-derived pharmaceuticals.The results are as follows:(1)Conducting disease investigation on 4 winter jujube bases and 2 mid-autumn crisp jujube bases in Hengyang area.The survey results show that winter jujube has anthrax,gray mold,scab,brown head disease,jujube witches’ broom disease,chalk disease,shrinking fruit disease and brown spot disease,et.al.Shrinking fruit disease and brown spot disease are the main diseases.Among them,the onset symptoms of brown spot disease are different from the known symptoms of jujube brown spot disease,which is a new type on jujube trees.Disease,in order to distinguish it,it is called jujube surface brown spot disease;mid-autumn crisp jujube has four kinds of diseases such as white rickets,coke leaf disease,shrinking fruit disease,jujube leaf black spot disease.The white rickets and jujube leaves black Spot disease are the main disease,which mainly damages the root neck and jujube leaves.(2)Separation,purification and preservation of the collected roots,stems,leaves and fruits,and the recovery test of the isolated strains,and determination of the pathogens for morphological observation and ITS identification,identified: the pathogen of fruit disease is Alternaria alternata,the pathogen of juvenile brown spot disease is Cladosporium tenuissimum,and the pathogen of jujube leaf black spot disease is Calonectria colhounii(the asexual stage is C.Cylindrocladium),a mid-autumn crispy jujube is a new host plant of Calonectria colhounii.(3)Using 9 kinds of traditional Chinese medicine acetone extract as experimental materials,the inhibitory effect on the pathogen of the constricted pathogen,Alternaria alternata and jujube leaf black spot disease,was found.The results showed that the quality of acetone extract in traditional Chinese medicine was found.Under the condition of concentration of 10mg/mL,inhibition effect of the saponin is 100% on the growth of the two pathogenic bacteria,and the antibacterial effect is significantly higher than other treatments;the inhibitory effect of schizonepeta and cinnamon on Alternaria alternata is relatively It is better that the inhibition rate of different growth stages of Alternaria alternata is above 40%;the growth inhibition rate of Nepeta and Rhubarb on Calonectria colhounii is 100%,and the inhibition rate of clove in the pre-growth stage of Calonectria colhounii was 100%,and it decreased after 96 h,but the inhibition rate was still above 65%.The specific antibacterial mechanism needs further study.(4)Five kinds of drugs(four biological agents and one chemical agent)were used as experimental materials to investigate the inhibitory effect on the pathogen of the shrinking disease of jujube,Alternaria alternata,and the pathogen of jujube leaf black spot.The results showed that the five pesticides had inhibitory effects on the growth of the pathogenicity of the pathogen,the pathogen of the shrinking disease of jujube,and the pathogen of the black spot of the black leaf spot.The antibacterial effect of the biopharmaceuticals is better than that of the chemical agent thiabium copper.For the Alternaria alternata,the bacteriostatic effects of the four biological agents are similar,but the 1500 times solution of garlic oil has better antibacterial effect(the inhibition rate on the growth of pathogens is over 40%,the inhibition diameter is 12.5 mm),followed by the multi-anti-mycin 1000 times solution;for the Calonectria colhounii,the garlic oil 1500 times solution has the best antibacterial effect(the inhibition rate on the growth of pathogens is over 50%,the bacteriostatic diameter is 10.7 mm),followed by 1000 times of polymycins and 800 times of Heqizheng medicinal herbs(inhibition rate is about 30%,bacteriostatic diameter is over 7.5 mm). |
