Replica platings among 9 species bacteria isolating from the stems, branches and leaves of poplar infected by INA bacterial canker were made.They are the pathogen Pantoea agglomerans , 7 species of Bacillus , and Pseu...Replica platings among 9 species bacteria isolating from the stems, branches and leaves of poplar infected by INA bacterial canker were made.They are the pathogen Pantoea agglomerans , 7 species of Bacillus , and Pseudomonas syringa . Results showed that the majority of poplar inhabiting bacteria are interspecific symbiont, the minority have antagonistic action in interspecies. It provided basic studies for further explore the roles of the poplar inhabiting bacteria in natural contracting of poplar bacterial canker, and also further select antagonistic microbe for effective biocontrol to poplar bacterial canker.展开更多
The isolation, culture and the active determination of poplar ice nucleation active (INA) bacteria and the inoculation tests in laboratory and field were conducted, and the varieties, distribution and number of poplar...The isolation, culture and the active determination of poplar ice nucleation active (INA) bacteria and the inoculation tests in laboratory and field were conducted, and the varieties, distribution and number of poplar INA bacteria and its pathoge-nicity and freezing injury property were determined. The study results showed that the INA bacteria widely spread on poplar in Northeast China and caused the frozen injury for poplar under the frost condition in Spring or Autumn, which was the key factor to induce INA bacterial canker. Through evaluation and investigation of different poplar varieties and inoculation tests, fine dis-ease-resistant varieties and strains of poplar suitable for Northeast China were selected. Further tests for strong seedling showed that burying cuttings in sand and covering with plastic film could effectively avoid the frostbite, frozen and drought damage, reduce INA bacteria infection, and promote poplar growth. INA bacterial canker was detected early by highly special-ized antiserums of INA bacteria and the agglutinated test of ring-shaped boundary surface. The inducers such as streptomycin, phenylmercuric acetae, salicylic acid and heat-killed bacteria to immerse cuttings, have obvious induced disease-resistant effect. Before poplar sprouted in early spring, through spraying the solution of frostbite agent, the control effect also was obvious.展开更多
Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected...Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected. Based on the compre-hensive analysis of main factors and induced factors, the standard for risk grades of this disease was promoted and northeast region of China was divided into 4 districts with different risk grades: seriously occurring district, commonly occurring district, occasionally occurring district, and un-occurring district. Nonlinear regression analysis for six model curves showed that the Richard growth model was suitable for describing the temporal dynamics of poplar INA bacterial canker. By stepwise variable selection method, the multi-variable linear regression forecasting equation was set up to predict the next year抯 disease index, and the GM (1,1) model was also set up by grey method to submit middle or long period forecast.展开更多
文摘Replica platings among 9 species bacteria isolating from the stems, branches and leaves of poplar infected by INA bacterial canker were made.They are the pathogen Pantoea agglomerans , 7 species of Bacillus , and Pseudomonas syringa . Results showed that the majority of poplar inhabiting bacteria are interspecific symbiont, the minority have antagonistic action in interspecies. It provided basic studies for further explore the roles of the poplar inhabiting bacteria in natural contracting of poplar bacterial canker, and also further select antagonistic microbe for effective biocontrol to poplar bacterial canker.
基金National Foundation of Ninth Five-Year Plan (No. 96-005-04-01-03).
文摘The isolation, culture and the active determination of poplar ice nucleation active (INA) bacteria and the inoculation tests in laboratory and field were conducted, and the varieties, distribution and number of poplar INA bacteria and its pathoge-nicity and freezing injury property were determined. The study results showed that the INA bacteria widely spread on poplar in Northeast China and caused the frozen injury for poplar under the frost condition in Spring or Autumn, which was the key factor to induce INA bacterial canker. Through evaluation and investigation of different poplar varieties and inoculation tests, fine dis-ease-resistant varieties and strains of poplar suitable for Northeast China were selected. Further tests for strong seedling showed that burying cuttings in sand and covering with plastic film could effectively avoid the frostbite, frozen and drought damage, reduce INA bacteria infection, and promote poplar growth. INA bacterial canker was detected early by highly special-ized antiserums of INA bacteria and the agglutinated test of ring-shaped boundary surface. The inducers such as streptomycin, phenylmercuric acetae, salicylic acid and heat-killed bacteria to immerse cuttings, have obvious induced disease-resistant effect. Before poplar sprouted in early spring, through spraying the solution of frostbite agent, the control effect also was obvious.
基金National Foundation of Ninth Five-Year Plan (No. 96-005-04-01-03).
文摘Through the methods of correlation analysis and main factor analysis, the relationship between the poplar INA bacte-rial canker and circumstances was analyzed and 9 main factors for affecting the disease were selected. Based on the compre-hensive analysis of main factors and induced factors, the standard for risk grades of this disease was promoted and northeast region of China was divided into 4 districts with different risk grades: seriously occurring district, commonly occurring district, occasionally occurring district, and un-occurring district. Nonlinear regression analysis for six model curves showed that the Richard growth model was suitable for describing the temporal dynamics of poplar INA bacterial canker. By stepwise variable selection method, the multi-variable linear regression forecasting equation was set up to predict the next year抯 disease index, and the GM (1,1) model was also set up by grey method to submit middle or long period forecast.
