Studying The Method Of Eliminating The Pathogen Of HLB From Scion And Young Tree In Citrus

HLB is a serious disease affecting the development of citrus industry.The preventions and treatments of HLB still rely on traditional methods in china at present,such as cutting down diseased trees,cultivation of virus-free seedlings,prevention of Psyllids.In this study,the chemical medicine treatment scion was used to screen out the medicion that could remove HLB pathogens.In the scion on a certain effect of the medicine and then on the citrus plant.The PCR and real-time PCR were used to detect HLB,and screen for effective chemical medicine treatments of HLB.In this study,the molecular detection and comparative analysis of Citrus Huanglong disease was carried out on materials from different local sources.One species of Bacillus was explored the colonization and optical microscopy identification.More results are as follows:1.Effect of small molecule compound on citrus scion removal from pathogen of citrus HLB in December 2015.Research shows(1)29 kinds of small molecule compounds treated in citrus scion are planted on vermiculite and observe the bud.Changes of QPCR relative expression of HLB before and after treatment,found that 2,5-dibromopyridine,1,2-benzisothiazol-3-one,2-hydrazine pyridine,3-(2-bromoethyl)indole,H,J,O,P,R,Z ten kinds of small molecule compounds more effective.(2)The initial screening of the ten small molecule compounds for repeated experiments in March2016,found that compounds B,J,O,Z,F more effective.2.Effect of five small molecule compounds and eighteen chemical medicine on citrus scion removal from pathogen of citrus HLB in December 2016.Research shows Bromamolone capsules,Norfloxacin,Amoxicillin dispersible tablets,compound 100,compound 106,compound 107 can remove HLB pathogens.The rates of detoxification were 33.3%.3.Effect of five chemical medicine and two antibiotic on citrus plants removal from pathogen of citrus HLB in April 2017.The live plants were treated by watering and drip irrigation.Norfloxacin is most effective.The rates of detoxification were 10%.The average number of new shoots were 5.2 sticks.The average growth length of new shoot were 14 cm.4.Isolation and identification of Bacillus GJ1: Electron microscopic observation of the existing GJ1 colonies showed that Short rod shape,1.41-1.49 μm long and 0.54-0.61μm wide.In the form of two-way asexual reproduction.Bacillus GJ1 were inoculated from four citrus plants.Isolation and purification of Bacillus and identification of Bacillus colonization.The isolated bacteria were compared with the known Bacillus under 40 x microscope.Found that the isolated bacteria are similar to the known Bacillus.The isolated bacteria and the known Bacillus were tested for Gram stain.Found that isolatedbacteria and known Bacillus are Gram-positive bacteria.Can be initially determined Bacillus GJ1 in citrus plants have been colonized.5.Detection of Huanglong disease in different areas:Hainan Qiongzhong,Fujian Yongchun,Yunnan Baoshan,Guangxi Chongzuo,Hainan Chengmai five areas of HLB detection to provide first-hand resources for the breeding of healthy nursery stock.There are differences in pathogens of HLB in different places.From the above results can be seen the detection rate of q-PCR was higher than that of conventional PCR.q-PCR is a more sensitive detection method than PCR.