Study On The Rapid Detecting And Monitor The Black Spot Disease Of Korla Pear In Export Orchards

This paper researches on Pathogen biological characteristics and rapid PCR detection methods forAlternaria alternata（Fr.）Keissl in export orchards of xinjiang.To establish real-time PCR assays methodfor the bacteria. Through monitoring the black spot disease of Korla pear in export orchards, the occurrenceperiod of black spot disease,severity of the disease and the relationship between meteorological factors andamount of spores have been understood.The occurrence regularity of black spot disease of Kolra pear inlocal was mastered.In order to clear the biological characteristics of the bacteria, the Growth of different culture conditionfor the Pathogens of Black spot disease of Korla pear has been studied.The fungus has been cultivated7days in different culture condition (including media, carbon sources, nitrogen source, temperature, acidityand alkalinity,light condition),and measured its colonies diameter and observe growth conditions ofMycelium and spores. And software SPSS18.0was used for statistical analysis for the relevant data. Theresult showed that the fungus could grow better on the PSA and PCA than Richard.The best carbon sourceis soluble starch and sucrose for the fungus and it could fully utilize the peptone.It could grow within15～35℃, and25～30℃was its optimum temperature. The fungus could grow in pH4.5to pH9.0, and itsoptimal pH was pH5.0to pH8.0. Full light was beneficial to the mycelium growth of A. alternate. In thewhole dark conditions contribute to the growth of spores.The bacteria was amplified on the PCR with fungal universal primers ITS1/ITS4.The PCR productswere cloned,restriction analysis and sequencing.Primers XJAF,XJAR and TaqMan probe XJAP weredesigned based on the unique sequence of the strains by DNAMAN software.The real-time PCR assaysmethod was established.Through system optimization and test results showed that this method can be usedfor the detection of pear black spot.The fungal spore trap was Placed in export orchards which for capturing A.alternata spores andcollecting flowers and fruits during the growing season, the spores were identifyed by microscopicexamination,isolated,PCR detected.Combining the local meteorological factors,monitoring results of blackspot pathogen spores of Korla pear and identification results of the bacteria to explore the occurrence ofdisease.Changes in the number of A.alternata spores in the orchard have obvious regularity,which showfewer spores in flowering,fast increase in the number of pathogen spores from fruit enlargement stage tofruit ripening stage,maximum number of pathogen spores the in the fruit picking period.The number ofspores in the orchard is related to temperature and humidity.The number was reaching the maximum whenthe temperature is28℃and the relative humidity is60%.A.alternate had already begun to infect Kolra pearin flowering,it was reproducing and spreading from the fruit growth to maturity.The black spot diseasestarted from the fruiting period,then became seriously.The most serious time was the fruit picking period.Inorder to understand the occurrence period of black spot disease,severity of the disease and the relationshipbetween meteorological factors and amount of spores in orchard,A.alternata spores was captured indifferent periods,the bacterias in flowers and fruit were identified and growth process of spore in the exportorchard was found.The occurrence regularity of black spot disease of Kolra pear in the local was mastered.