Race-specific resistance and field resistance of 30 rice blast resistance monogenic lines derived from different resources were evaluated. The spectra of resistance to 163 Magnaporthe grisea isolates collected from in...Race-specific resistance and field resistance of 30 rice blast resistance monogenic lines derived from different resources were evaluated. The spectra of resistance to 163 Magnaporthe grisea isolates collected from indica rice in Guangdong Province, China ranged from 0.6% to 89.6%. Most of the monogenic lines showed a narrow resistance spectrum and high susceptibility in rice blast area, whereas the lines with Pikh and Pi1(t) had the broad resistance spectra of 89.6% and 82.2% respectively, showing a high and stable blast resistance in fields. According to the cluster analysis of specific resistance to 163 blast isolates tested, the 30 monogenic lines were divided into 15 groups, and based on the principal factor analysis, nine kinds of race-specific resistance were identified. Pik, Piz5, Pi9 and Pish can be used as candidate resistance genes for rice breeding since their specific resistance differed from those of the backbone parents in Guangdong, China. Gene pyramiding of Pikh [or Pi1(t)], Pi9 (or Piz5) and Pish (or Pita2) will be effective to obtain broad-spectrum blast resistance in rice breeding program in Guangdong, China. The strategies for studying and application of rice blast resistance genes were discussed.展开更多
Six isolates of Magnaporthe grisea were selected to inoculate on 10 Chinese leading maintainer lines (B-lines), 14 restorer lines (R-lines) and their F1 hybrid plants. In the tested rice materials, R-lines were proved...Six isolates of Magnaporthe grisea were selected to inoculate on 10 Chinese leading maintainer lines (B-lines), 14 restorer lines (R-lines) and their F1 hybrid plants. In the tested rice materials, R-lines were proved to be more resistant to blast than B-lines. The resistance frequency of about 25% F1 hybrid plants was less than their parents. In addition, 26 isolates of M. grisea collected from different rice growing areas of China were inoculated on 13 new improved hybrid rice combinations. The resistance frequencies of 5 improved hybrids were better than those of the controls and leading varieties in rice production of China.展开更多
The expression of a protein elicitor from Magnaporthe griesea and its biological function in activating resistance in rice （Oryza safiva L） were reported. The gene of elicitor was expressed in Escherichia colicells ...The expression of a protein elicitor from Magnaporthe griesea and its biological function in activating resistance in rice （Oryza safiva L） were reported. The gene of elicitor was expressed in Escherichia colicells and produced a His6-fusion protein with 42 kD apparent molecular weight on SDS-PAGE. The purified protein could induce the resistance to blast disease, with the control efficiency of 46.47% and 36.41% at the 14^th day and the 21^st day after blast inoculation, respectively. After treatment with the expressed protein, the phenylalanine ammonia-lyase （PAL） and peroxidase （POD） activities were promoted in rice plants, meanwhile, the transcription levels of STKM, FAD, PBZ1 and PR1 genes were increased in rice plants. Moreover, after comparing the profile of total rice leaf proteins on two-dimensional electrophoresis gel, about 14 proteins were found to be increased in expression level after the expressed protein treatment. All the results indicated that the expressed protein could act as an elicitor to trigger the resistance in rice.展开更多
A rapidly growing number of successful genome sequencing projects in plant pathogenic fungi greatly increase the demands for tools and methodologies to study fungal pathogenicity at genomic scale. Magnaporthe oryzae i...A rapidly growing number of successful genome sequencing projects in plant pathogenic fungi greatly increase the demands for tools and methodologies to study fungal pathogenicity at genomic scale. Magnaporthe oryzae is an economically important plant pathogenic fungus whose genome is fully sequenced. Recently we have reported the development and application of functional genomics platform technologies in M. oryzae. This model approach would have many practical ramifications in design and implementation of upcoming functional genomics studies of filamentous fungi aimed at understanding fungal pathogenicity.展开更多
A genetic cross between Oryza isolate Y93-164a-1 and Eleusine isolate SA98-4 was established, and the pathogenicity of 151 F1 progeny isolates was investigated on both host plants rice and finger millet. Results showe...A genetic cross between Oryza isolate Y93-164a-1 and Eleusine isolate SA98-4 was established, and the pathogenicity of 151 F1 progeny isolates was investigated on both host plants rice and finger millet. Results showed that the segregation of pathogenicity in this genetic cross was abnormal, i.e., most of the progeny isolates were nonpathogenic on both host plants. However, no abnormal segregation was observed when middle repetitive sequence MGR586 and 31 single-copy RFLP markers from all of the chromosomes were genetically analyzed. At the same time, comparison of the chromosomal organization among two pairs of parental isolates did not find any genomic abnormity. These results suggested that the ＂abnormal＂ inheritance of pathogenicity in this cross was most likely due to the reassortment of numerous host species specificity genes but not the biased segregation of the host species specificity genes. The host species specificities in M. grisea were likely to be multigenically controlled, at least in the genetic cross involving rice pathogen and the grasses pathogen other than rice.展开更多
[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Pr...[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Province where rice blast occurs frequently,60 isolates which were pathotyped against two sets of host differentials:Chinese host differentials and CO39 NILs,were obtained.Then,20 pathotypes with the six indica host differentials(CO39 NILs) were observed,while 13 pathotypes in four race groups were observed out of the same single spore isolates with Chinese host differentials which consists of three indica cultivars and four japonica cultivars.The diversity of the pathotypes of M.grisea populations tested by CO39 NILs was 2.54 and the pathotype 137.1 occurred at predominantly high frequency(21.67%).The diversity of physiological races of M.grisea populations tested by Chinese host differentials was 1.22 and the race group ZA occurred at predominantly high frequency(73.33%).The diversity of physiological races of M.grisea in Chongyang and Yuan'an were also calculated.Overall,the diversity of pathotypes of M.grisea in Yuan'an was higher than that in Chongyang with the two sets of the host differentials.[Conclusion] This study provided current information on the pathotype spectrum of M.grisea populations in the rice fields of Hubei Province to allow the formulation of viable strategies for blast resistance breeding programs in Hubei Province.展开更多
基金supported by the ‘948’ Project of Ministry of Agriculture, China (Grant No. 2006-G61)the Natural Science Foundation of Guangdong Province, China (Grant No. 04101156)+2 种基金the Science and Technique Project of Guangdong Province, China (Grant No. 2005B20101006 and No. 0711124900076)the Science and Technique Project of Guangzhou City, China (Grant No. 2005C12E0061)the Science Fundamental Research Foundation of Guangdong Academy of Agricultural Sciences, China.
文摘Race-specific resistance and field resistance of 30 rice blast resistance monogenic lines derived from different resources were evaluated. The spectra of resistance to 163 Magnaporthe grisea isolates collected from indica rice in Guangdong Province, China ranged from 0.6% to 89.6%. Most of the monogenic lines showed a narrow resistance spectrum and high susceptibility in rice blast area, whereas the lines with Pikh and Pi1(t) had the broad resistance spectra of 89.6% and 82.2% respectively, showing a high and stable blast resistance in fields. According to the cluster analysis of specific resistance to 163 blast isolates tested, the 30 monogenic lines were divided into 15 groups, and based on the principal factor analysis, nine kinds of race-specific resistance were identified. Pik, Piz5, Pi9 and Pish can be used as candidate resistance genes for rice breeding since their specific resistance differed from those of the backbone parents in Guangdong, China. Gene pyramiding of Pikh [or Pi1(t)], Pi9 (or Piz5) and Pish (or Pita2) will be effective to obtain broad-spectrum blast resistance in rice breeding program in Guangdong, China. The strategies for studying and application of rice blast resistance genes were discussed.
文摘Six isolates of Magnaporthe grisea were selected to inoculate on 10 Chinese leading maintainer lines (B-lines), 14 restorer lines (R-lines) and their F1 hybrid plants. In the tested rice materials, R-lines were proved to be more resistant to blast than B-lines. The resistance frequency of about 25% F1 hybrid plants was less than their parents. In addition, 26 isolates of M. grisea collected from different rice growing areas of China were inoculated on 13 new improved hybrid rice combinations. The resistance frequencies of 5 improved hybrids were better than those of the controls and leading varieties in rice production of China.
文摘The expression of a protein elicitor from Magnaporthe griesea and its biological function in activating resistance in rice （Oryza safiva L） were reported. The gene of elicitor was expressed in Escherichia colicells and produced a His6-fusion protein with 42 kD apparent molecular weight on SDS-PAGE. The purified protein could induce the resistance to blast disease, with the control efficiency of 46.47% and 36.41% at the 14^th day and the 21^st day after blast inoculation, respectively. After treatment with the expressed protein, the phenylalanine ammonia-lyase （PAL） and peroxidase （POD） activities were promoted in rice plants, meanwhile, the transcription levels of STKM, FAD, PBZ1 and PR1 genes were increased in rice plants. Moreover, after comparing the profile of total rice leaf proteins on two-dimensional electrophoresis gel, about 14 proteins were found to be increased in expression level after the expressed protein treatment. All the results indicated that the expressed protein could act as an elicitor to trigger the resistance in rice.
基金a grant from Biogreen 21 Project (No. 20080401034044)the Rural Development Administration of Korea, the Crop Functional Genomics Center (No. CG1141) of the 21st Century Frontier Research Program funded by the Ministry of Science and Technology of Koreathe Korean Research Foundation Grant (No. KRF-2006-005-J04701)
文摘A rapidly growing number of successful genome sequencing projects in plant pathogenic fungi greatly increase the demands for tools and methodologies to study fungal pathogenicity at genomic scale. Magnaporthe oryzae is an economically important plant pathogenic fungus whose genome is fully sequenced. Recently we have reported the development and application of functional genomics platform technologies in M. oryzae. This model approach would have many practical ramifications in design and implementation of upcoming functional genomics studies of filamentous fungi aimed at understanding fungal pathogenicity.
基金supported by a project (11660050) from the Ministry of Education, Culture, Sports, ScienceTechnology of Japan and the project of the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Huazhong Agricultural University, China(4002-30541)
文摘A genetic cross between Oryza isolate Y93-164a-1 and Eleusine isolate SA98-4 was established, and the pathogenicity of 151 F1 progeny isolates was investigated on both host plants rice and finger millet. Results showed that the segregation of pathogenicity in this genetic cross was abnormal, i.e., most of the progeny isolates were nonpathogenic on both host plants. However, no abnormal segregation was observed when middle repetitive sequence MGR586 and 31 single-copy RFLP markers from all of the chromosomes were genetically analyzed. At the same time, comparison of the chromosomal organization among two pairs of parental isolates did not find any genomic abnormity. These results suggested that the ＂abnormal＂ inheritance of pathogenicity in this cross was most likely due to the reassortment of numerous host species specificity genes but not the biased segregation of the host species specificity genes. The host species specificities in M. grisea were likely to be multigenically controlled, at least in the genetic cross involving rice pathogen and the grasses pathogen other than rice.
基金Supported by the Key Project of the National 11th Five-Year Plan of China (2006BADO8A04-06)
文摘[Objective] This study aimed to explore the pathotype structure of Magnaporthe grisea in Chongyang and Yuan'an in Hubei Province,China.[Method] From the rice-growing fields of Chongyang and Yuan'an in Hubei Province where rice blast occurs frequently,60 isolates which were pathotyped against two sets of host differentials:Chinese host differentials and CO39 NILs,were obtained.Then,20 pathotypes with the six indica host differentials(CO39 NILs) were observed,while 13 pathotypes in four race groups were observed out of the same single spore isolates with Chinese host differentials which consists of three indica cultivars and four japonica cultivars.The diversity of the pathotypes of M.grisea populations tested by CO39 NILs was 2.54 and the pathotype 137.1 occurred at predominantly high frequency(21.67%).The diversity of physiological races of M.grisea populations tested by Chinese host differentials was 1.22 and the race group ZA occurred at predominantly high frequency(73.33%).The diversity of physiological races of M.grisea in Chongyang and Yuan'an were also calculated.Overall,the diversity of pathotypes of M.grisea in Yuan'an was higher than that in Chongyang with the two sets of the host differentials.[Conclusion] This study provided current information on the pathotype spectrum of M.grisea populations in the rice fields of Hubei Province to allow the formulation of viable strategies for blast resistance breeding programs in Hubei Province.
