Research On The Identification Ot Pathogen And Integrated Control Of Anthracnose On Zizphus Jujube Mill.cv.lingwuchangzao

The research observed symptom of anthracnose on Zizphus jujube Mill.cv.Lingwuchangzao and inquired field pathogeny sporulation in Da Quan forest farm on 2018.This study includes pathogeny separation and evaluation;biological characteristics of pathogen;antagonistic bacteria selection;investigation of infection conditions;fungicides against pathogen and control anthracnose in field.1.The sample from Zizphus jujuba Mill.cv.Lingwuchangzao was identified as Colletotrichum gloeosporioides by the characteristics of morphology,pathogenicity test and sequence analysis of the internal transcribed spacer region of the ribosomal DNA(rDNA ITS).2.The results of biological characteristics of Colletotrichum gloeosporioides showed that the glucose,fructopyranose and saccharose in C sources,the beef extract and peptone in N sources and PDA could dramatically increase the growth rate of mycelia.The most suitable temperature,pH and light conditions for the growth of Colletotrichum gloeosporioides were 7,25～30℃ and alternation between light and dark,the lethal temperatures of conidia were 50℃ 15 min or 55℃ 5 min,the lethal temperatures of mycelium were 60℃ 30 min or 65℃ 5 min.3.The optimum infection condition of pathogen of speckle disease were trauma on jujube fruit and leaves,ambient temperature range in 28-32℃,RH>85%,12L/12D,conspore is the best Infection form.4.In the process of pathogen infection,MDA content of jujube fruits and leaves increases over time;SOD,POD and PPO showed a tendency of increasing and decreasing after inoculation;POD and PPO have synergistic effects,responsed to pathogen invasion before SOD,it matched the physiological and biochemical changes of plant adversity.5.Biological controlling agents against pathogen of jujube anthracnose were screened and its inhibition rate were 73.24%.According to morphological,biophysiological and biochemnical characteristics and 16S rDNA sequence homology,the strain was identified as Bacillus methylotrophicus.6.The indoor toxicity of 41ow toxic chemical pesticides and 4 biological pesticides was measured,and 2 low toxic chemical pesticides(Pyraclostrobin and Dithianon),2 biological pesticides(Liangguoan and Jiangwenjing)with good control effect were selected.Because of the strong inhibitory effect of the two biopesticides on the growth of antagonistic JM1,the interval between field application of biopesticides and antagonistic bacterial suspensions should be set.Mixing of two low-toxic chemical pesticides can reduce the amount of spore in pathogenic field.In biological pesticides,the best effect was to combine the 200 times Liangguoan and 250 times Jiangwenjing distemper by volume ratio 1:1.The antagonistic antimicrobial suspension can inhibit the expansion of the disease spot.