Bacterial wilt (BW) caused by Ralstonia solanacearum is an important constraint to peanut (Arachis hypogaea L.) production in several Asian and African countries, and planting BW-resistant cultivars is the most fe...Bacterial wilt (BW) caused by Ralstonia solanacearum is an important constraint to peanut (Arachis hypogaea L.) production in several Asian and African countries, and planting BW-resistant cultivars is the most feasible method for controlling the disease. Although several BW-resistant peanut germplasm accessions have been identified, the genetic diversity among these has not been properly investigated, which has impeded efficient utilization. In this study, the genetic relationships of 31 peanut genotypes with various levels of resistance to BW were assessed based on SSR and AFLP analyses. Twenty-nine of 78 SSR primers and 32 of 126 AFLP primer combinations employed in this study were polymorphic amongst the peanut genotypes tested. The SSR primers amplified 91 polymorphic loci in total with an average of 3.14 alleles per primer, and the AFLP primers amplified 72 polymorphic loci in total with an average of 2.25 alleles per primer. Four SSR primers (14H06, 7G02, 3A8, 16C6) and one AFLP primer (P1M62) were found to be most efficient in detecting diversity. The genetic distance between pairs of genotypes ranged from 0.12 to 0.94 with an average of 0.53 in the SSR data and from 0.06 to 0.57 with an average of 0.25 in the AFLP data. The SSR-based estimates of the genetic distance were generally larger than that based on the AFLP data. The genotypes belonging to subsp, fastigiata possessed wider diversity than that of subsp, hypogaea. The clustering of genotypes based on the SSR and AFLP data were similar but the SSR clustering was more consistent with morphological classification ofA. hypogaea. Optimum diverse genotypes of both subsp, hypogaea and subsp.fastigiata can be recommended based on this analysis for developing mapping populations and breeding for high yielding and resistant cultivars.展开更多
[Objective] The aim was to study resistance of major and backup rice cul- tivars against Ustilaginoidea virens. [Method] Experiments and surveys were made on resistance of seventeen backup rice cultivars and some majo...[Objective] The aim was to study resistance of major and backup rice cul- tivars against Ustilaginoidea virens. [Method] Experiments and surveys were made on resistance of seventeen backup rice cultivars and some major cultivars in Anhui Province to identify resistance of different rice cultivars. [Result] Yanjing No.9, 80You 226, Tianxie No.l, A01 Xian, Lvjingnuo No.6 were moderate resistant; A03 Xian and Yangjing 636 were susceptible and the rest ten showed moderate susceptibility. Based on surveys on major rice cultivars, most of Liangyou rice series are suscept- able and novel Liangyou Xiang 4 enjoys resistance to certain extent. [Conclusion] The research provided references for resistance of rice against diseases in Anhui Province.展开更多
Based on the results of the national regional trail for winter rapeseed in four groups,including the upper reaches,middle reaches and lower reaches of Yangtze River and Huang-Huai region in the past twenty years,new v...Based on the results of the national regional trail for winter rapeseed in four groups,including the upper reaches,middle reaches and lower reaches of Yangtze River and Huang-Huai region in the past twenty years,new varieties of winter rapeseed showed upward trend in average yield,the yield level in Huang-huai group was higher than other groups.The changes of average effective pods per plant were not significant in any group,but the number of grain per pod and 1 000-grain weight showed increase trend.However,the increment of grains per pod in three Yangtze River groups was higher than that in Huang-Huai River group,while the increment of 1 000-grain weight was just opposite.The incidence rate of Sclerotinia sclerotiorum and viral disease in new varieties of winter rapeseed obviously decreased,and the incidence rate of S.sclerotiorum decreased lower than 5%.Genetic improvement for winter rapeseed should be focus on the number of grain per pod and 1 000-grain weight in the future,and yield level of new varieties in all four groups is expected to increase.展开更多
[Objective] Aimed to lay a scientific foundation for eggplant resistant breeding, the resistant field identification of eggplant resources to Verticillium wilt was carried out. [Method] Test materials were 35 eggplant...[Objective] Aimed to lay a scientific foundation for eggplant resistant breeding, the resistant field identification of eggplant resources to Verticillium wilt was carried out. [Method] Test materials were 35 eggplant resources, which were collected from various places in Sichuan province since 2001. These eggplant resources were made resistance evaluation to Verticillium wilt by watering injured roots with Verticillium dahliae spore suspension. [Result] The eggplant resources had good resistance to Verticillium wilt. Among 35 evaluated resources, 10 resources like 242-9OP, 41-1,35-R5, etc. were resistant, while 23 resources like 68 ×47, Zizaoqie, 32-1, etc. were tolerant. Some resistant resources like 41-1,35-R5, 47-R1, etc. had been transferred into new resistant varieties like EF9910, etc. by breeding institutes. [Conclusion] The resistant level and future resistance breeding direction of eggplant resources in Sichuan were clarified by the resistance evaluation of eggplant resources so as to provide a technical guidance for eggplant resistance breeding.展开更多
A brief review on the development of wheat germplasm with introduced powdery mildew and scab resistance from Haynaldia villosa Sch. and Leymus racemosus Lam., Roegneria ciliaris (Trin.) Nevski as well as R. kamoji C. ...A brief review on the development of wheat germplasm with introduced powdery mildew and scab resistance from Haynaldia villosa Sch. and Leymus racemosus Lam., Roegneria ciliaris (Trin.) Nevski as well as R. kamoji C. Koch respectively was made. In the course of germplasm development, genome analysis by means of chromosome banding, genomic in situ hybridization (GISH) or fluorescence in situ hybridization (FISH), molecular markers, particularly restriction fragment length polymorphism (RFLP) coupled with aneuploid analysis was employed for the purpose of improving breeding efficiency. Potential use of such germplasm in wheat breeding practice, basic studies and some related problems were also discussed.展开更多
Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.)....Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.). More than 150 plantlets regenerated after 4-5 months of culture. The regenerated plants were trifoliate with well developed root systems. Root_tip chromosome counting of more than 20 randomly selected plants revealed that they were all tetraploids (2n=4x=36). RAPD analysis of 7 randomly selected plants verified their hybridity. Inoculation of citrus Phytophthora parasitica Dastar toxin on leaves of somatic hybrids and both parental genotypes showed that Page tangelo was moderately susceptible, and trifoliate orange was highly resistant while the somatic hybrids were resistant. The potential of this somatic hybrid as rootstock is also discussed.展开更多
This paper reviewed the research advances of Ug99 and its resistance breeding from the aspects of its discovery, race variation, pathogenicity, distribution, spread, exploration of relative resistant genes, linked mol...This paper reviewed the research advances of Ug99 and its resistance breeding from the aspects of its discovery, race variation, pathogenicity, distribution, spread, exploration of relative resistant genes, linked molecular marker selection and resistance breeding strategies, to provide basis for comprehensive understanding of the new Puccinia graminis f. sp. tritici race Ug99 and its potential threat to wheat production. Ug99 is a new Puccinia grarninis f. sp. tritici race with high variability, strong pathogenicity and rapid spread speed, which is likely to cause global damages to world wheat production. We should strengthen the exploration and utilization of new resistance genes in wheat and relative species and breeding of new wheat varieties with durable resistance, to control and prevent damages caused by Ug99 and its variants.展开更多
In order to determine the resistance of leading rice varieties to rice blast in Guangxi, three natural induction rice blast nurseries were established in Cenxi, Sanjiang and Yongfu. The resistance of the 45 leading ri...In order to determine the resistance of leading rice varieties to rice blast in Guangxi, three natural induction rice blast nurseries were established in Cenxi, Sanjiang and Yongfu. The resistance of the 45 leading rice varieties in Guangxi to rice blast was determined under conditions of spray inoculation and natural induction at seedling stage. The results showed that resistance frequencies of the 45 leading rice varieties ranged from 8.33% to 94.44%. Among the 45 tested varieties, there were 8 varieties of which the resistance frequencies were all higher than 80%, accounting for 17.78%; there were 11 varieties of which the resistance frequencies ranged from 50% to 80%, accounting for 24.44%; the resistance frequencies of the remaining varieties were all lower than 50%, accounting for 57.78% of the total tested varieties. The twoconsecutive-year determination results showed none of the 45 leading rice varieties showed resistance to rice blast. In 2010, there were 26, 12 and 7 varieties that were moderately sensitive, sensitive and greatly sensitive to rice blast respectively, accounting for 57.78%, 26.67% and 15.56% of the total tested varieties. In 2011, there were 16, 23 and 12 varieties that were moderately sensitive, sensitive and greatly sensitive to rice blast respectively, accounting for 35.56%, 51.11% and 13.33%. The overall resistance of the 45 leading rice varieties trended to be decreased year by year. So in rice production, they should be selected properly.展开更多
[Objective] The aim of this study was to screen rice strip virus (RSV)-resistant landraces. [Method] The resistance of 119 rice landraces to rice stripe virus was identified in field spontaneously infected with sma...[Objective] The aim of this study was to screen rice strip virus (RSV)-resistant landraces. [Method] The resistance of 119 rice landraces to rice stripe virus was identified in field spontaneously infected with smal plant-hopper. [Result] There were 55 landraces resistant to rice strip disease in 56 indica rice landraces, but on-ly two resistant to rice strip disease in 63 japonica rice landraces. [Conclusion] The results revealed that there were abundant rice landscapes resistant to RSV in Chi-na, and these varieties can be used to develop more genes resistant to RSV.展开更多
Chike (accession number Su1900), a Chinese native wheat (Triticum aestivum L.) variety, is resistant to the currently prevailing physiological races of Puccinia striiformis Westend. f. sp. tritici in China. Geneti...Chike (accession number Su1900), a Chinese native wheat (Triticum aestivum L.) variety, is resistant to the currently prevailing physiological races of Puccinia striiformis Westend. f. sp. tritici in China. Genetic analysis indicated that resistance to the physiological race CY32 of the pathogen in the variety was controlled by one dominant gene. In this study, BSA (bulked segregant analysis) methods and SSRs (simple sequence repeats) marker polymorphic analysis are used to map the gene. The resistant and susceptible DNA bulks were prepared from the segregating F2 population of the cross between Taichung 29, a susceptible variety as maternal parent, and Chike as paternal parent. Over 400 SSR primers were screened, and five SSR markers Xwmc44, Xgwm259, Xwmc367, Xcfa2292, and Xbarc80 on the chromosome arm 1BL were found to be polymorphic between the resistant and the susceptible DNA bulks as well as their parents. Genetic linkage was tested on segregating F2 population with 200 plants, including 140 resistant and 60 susceptible plants. All the five SSR markers were linked to the stripe rust resistance gene in Chike. The genetic distances for the markers Xwmc44, Xgwm259, Xwmc367, Xcfa2292, and Xbarc80 to the target gene were 8.3 cM, 9.1 cM, 17.2 cM, 20.6 cM, and 31.6 cM, respectively. Analysis using 21 nulli-tetrasomic Chinese Spring lines further confirmed that all the five markers were located on chromosome lB. On the basis of the above results, it is reasonable to assume that the major stripe rust resistance gene YrChk in Chike was located on the chromosome arm 1BL, and its comparison with the other stripe rust resistance genes located on 1B suggested that YrChk may be a novel gene that provides the resistance against stripe rust in Chike. Exploration and utilization of resources of disease resistance genes in native wheat varieties will be helpful both to diversify the resistance genes and to amend the situation of resistance gene simplification in the commercial wheat cultivars in China.展开更多
Objective: To observe human to mouse one way mixed lymphocyte(MLC); And to set up the xeno-grats verse host disease Xeno-graft host disease(XGVHD) model,probing its immunologic mechamism.Methods: Mouse splenic lympho...Objective: To observe human to mouse one way mixed lymphocyte(MLC); And to set up the xeno-grats verse host disease Xeno-graft host disease(XGVHD) model,probing its immunologic mechamism.Methods: Mouse splenic lymphocyte were collected in asepsis and treated by mitomycin as activating cell. Human Peripheral blood lymphocytes (hPBL)were separated and gathered as reacting cell; Mouse splenic lymphocyte and hPBL were mixed to incubate for a week. Destroying recipient (mouse) immune system by total body irradiation (TBI) and intraperitoneal injecting CTX、MTX; Separating and collecting hPBL; Injecting hPBL to mouse by caudal vein. Results; ①HPBL in the experiment groups(mixed mouse lymphocyte) proliferated obviously, the amount of 3H-TdR in corporation increased evidently(P<0.05); The mean percentage of CD 4、CD 8、IgG 、IgM positive cells rose markedly. ②Experiment groups,the hPBL were found in the spleen and kidney tissue, fas protein expressing, we occasionally discovered and apoptosis cells.Conclusion: The human to mouse one-way MLC has obvious lymphocyte proliferation. By these means,we succeed in inducing XGVHD and setting up a XGVHD model.展开更多
基金This work was supported by the National Natural Science Foundation of China(NSFC)(No.30070521 and 30270840).
文摘Bacterial wilt (BW) caused by Ralstonia solanacearum is an important constraint to peanut (Arachis hypogaea L.) production in several Asian and African countries, and planting BW-resistant cultivars is the most feasible method for controlling the disease. Although several BW-resistant peanut germplasm accessions have been identified, the genetic diversity among these has not been properly investigated, which has impeded efficient utilization. In this study, the genetic relationships of 31 peanut genotypes with various levels of resistance to BW were assessed based on SSR and AFLP analyses. Twenty-nine of 78 SSR primers and 32 of 126 AFLP primer combinations employed in this study were polymorphic amongst the peanut genotypes tested. The SSR primers amplified 91 polymorphic loci in total with an average of 3.14 alleles per primer, and the AFLP primers amplified 72 polymorphic loci in total with an average of 2.25 alleles per primer. Four SSR primers (14H06, 7G02, 3A8, 16C6) and one AFLP primer (P1M62) were found to be most efficient in detecting diversity. The genetic distance between pairs of genotypes ranged from 0.12 to 0.94 with an average of 0.53 in the SSR data and from 0.06 to 0.57 with an average of 0.25 in the AFLP data. The SSR-based estimates of the genetic distance were generally larger than that based on the AFLP data. The genotypes belonging to subsp, fastigiata possessed wider diversity than that of subsp, hypogaea. The clustering of genotypes based on the SSR and AFLP data were similar but the SSR clustering was more consistent with morphological classification ofA. hypogaea. Optimum diverse genotypes of both subsp, hypogaea and subsp.fastigiata can be recommended based on this analysis for developing mapping populations and breeding for high yielding and resistant cultivars.
基金Supported by Demonstration and Extension Project of Technology Controlling Ustilaginoidea virens(11E1110)~~
文摘[Objective] The aim was to study resistance of major and backup rice cul- tivars against Ustilaginoidea virens. [Method] Experiments and surveys were made on resistance of seventeen backup rice cultivars and some major cultivars in Anhui Province to identify resistance of different rice cultivars. [Result] Yanjing No.9, 80You 226, Tianxie No.l, A01 Xian, Lvjingnuo No.6 were moderate resistant; A03 Xian and Yangjing 636 were susceptible and the rest ten showed moderate susceptibility. Based on surveys on major rice cultivars, most of Liangyou rice series are suscept- able and novel Liangyou Xiang 4 enjoys resistance to certain extent. [Conclusion] The research provided references for resistance of rice against diseases in Anhui Province.
文摘Based on the results of the national regional trail for winter rapeseed in four groups,including the upper reaches,middle reaches and lower reaches of Yangtze River and Huang-Huai region in the past twenty years,new varieties of winter rapeseed showed upward trend in average yield,the yield level in Huang-huai group was higher than other groups.The changes of average effective pods per plant were not significant in any group,but the number of grain per pod and 1 000-grain weight showed increase trend.However,the increment of grains per pod in three Yangtze River groups was higher than that in Huang-Huai River group,while the increment of 1 000-grain weight was just opposite.The incidence rate of Sclerotinia sclerotiorum and viral disease in new varieties of winter rapeseed obviously decreased,and the incidence rate of S.sclerotiorum decreased lower than 5%.Genetic improvement for winter rapeseed should be focus on the number of grain per pod and 1 000-grain weight in the future,and yield level of new varieties in all four groups is expected to increase.
基金Supported by Breeding Key Project of Sichuan Province(2006-yzgg-25)~~
文摘[Objective] Aimed to lay a scientific foundation for eggplant resistant breeding, the resistant field identification of eggplant resources to Verticillium wilt was carried out. [Method] Test materials were 35 eggplant resources, which were collected from various places in Sichuan province since 2001. These eggplant resources were made resistance evaluation to Verticillium wilt by watering injured roots with Verticillium dahliae spore suspension. [Result] The eggplant resources had good resistance to Verticillium wilt. Among 35 evaluated resources, 10 resources like 242-9OP, 41-1,35-R5, etc. were resistant, while 23 resources like 68 ×47, Zizaoqie, 32-1, etc. were tolerant. Some resistant resources like 41-1,35-R5, 47-R1, etc. had been transferred into new resistant varieties like EF9910, etc. by breeding institutes. [Conclusion] The resistant level and future resistance breeding direction of eggplant resources in Sichuan were clarified by the resistance evaluation of eggplant resources so as to provide a technical guidance for eggplant resistance breeding.
文摘A brief review on the development of wheat germplasm with introduced powdery mildew and scab resistance from Haynaldia villosa Sch. and Leymus racemosus Lam., Roegneria ciliaris (Trin.) Nevski as well as R. kamoji C. Koch respectively was made. In the course of germplasm development, genome analysis by means of chromosome banding, genomic in situ hybridization (GISH) or fluorescence in situ hybridization (FISH), molecular markers, particularly restriction fragment length polymorphism (RFLP) coupled with aneuploid analysis was employed for the purpose of improving breeding efficiency. Potential use of such germplasm in wheat breeding practice, basic studies and some related problems were also discussed.
文摘Protoplasts of Page tangelo (Citrus reticulata Blanco×C. paradisi Macf.) cell suspension culture were electrically fused with mesophyll protoplasts isolated from trifoliate orange (Poncirus trifoliata (L.) Raf.). More than 150 plantlets regenerated after 4-5 months of culture. The regenerated plants were trifoliate with well developed root systems. Root_tip chromosome counting of more than 20 randomly selected plants revealed that they were all tetraploids (2n=4x=36). RAPD analysis of 7 randomly selected plants verified their hybridity. Inoculation of citrus Phytophthora parasitica Dastar toxin on leaves of somatic hybrids and both parental genotypes showed that Page tangelo was moderately susceptible, and trifoliate orange was highly resistant while the somatic hybrids were resistant. The potential of this somatic hybrid as rootstock is also discussed.
基金Supported by Starting Fund for Introduction of Qualified Personnel from Henan Agricultural University (30300190)~~
文摘This paper reviewed the research advances of Ug99 and its resistance breeding from the aspects of its discovery, race variation, pathogenicity, distribution, spread, exploration of relative resistant genes, linked molecular marker selection and resistance breeding strategies, to provide basis for comprehensive understanding of the new Puccinia graminis f. sp. tritici race Ug99 and its potential threat to wheat production. Ug99 is a new Puccinia grarninis f. sp. tritici race with high variability, strong pathogenicity and rapid spread speed, which is likely to cause global damages to world wheat production. We should strengthen the exploration and utilization of new resistance genes in wheat and relative species and breeding of new wheat varieties with durable resistance, to control and prevent damages caused by Ug99 and its variants.
文摘In order to determine the resistance of leading rice varieties to rice blast in Guangxi, three natural induction rice blast nurseries were established in Cenxi, Sanjiang and Yongfu. The resistance of the 45 leading rice varieties in Guangxi to rice blast was determined under conditions of spray inoculation and natural induction at seedling stage. The results showed that resistance frequencies of the 45 leading rice varieties ranged from 8.33% to 94.44%. Among the 45 tested varieties, there were 8 varieties of which the resistance frequencies were all higher than 80%, accounting for 17.78%; there were 11 varieties of which the resistance frequencies ranged from 50% to 80%, accounting for 24.44%; the resistance frequencies of the remaining varieties were all lower than 50%, accounting for 57.78% of the total tested varieties. The twoconsecutive-year determination results showed none of the 45 leading rice varieties showed resistance to rice blast. In 2010, there were 26, 12 and 7 varieties that were moderately sensitive, sensitive and greatly sensitive to rice blast respectively, accounting for 57.78%, 26.67% and 15.56% of the total tested varieties. In 2011, there were 16, 23 and 12 varieties that were moderately sensitive, sensitive and greatly sensitive to rice blast respectively, accounting for 35.56%, 51.11% and 13.33%. The overall resistance of the 45 leading rice varieties trended to be decreased year by year. So in rice production, they should be selected properly.
文摘[Objective] The aim of this study was to screen rice strip virus (RSV)-resistant landraces. [Method] The resistance of 119 rice landraces to rice stripe virus was identified in field spontaneously infected with smal plant-hopper. [Result] There were 55 landraces resistant to rice strip disease in 56 indica rice landraces, but on-ly two resistant to rice strip disease in 63 japonica rice landraces. [Conclusion] The results revealed that there were abundant rice landscapes resistant to RSV in Chi-na, and these varieties can be used to develop more genes resistant to RSV.
基金the National Natural Science Foundation of China (No. 30571157) the National Basic Research Program (973 Program) (No. 2006CB100203).
文摘Chike (accession number Su1900), a Chinese native wheat (Triticum aestivum L.) variety, is resistant to the currently prevailing physiological races of Puccinia striiformis Westend. f. sp. tritici in China. Genetic analysis indicated that resistance to the physiological race CY32 of the pathogen in the variety was controlled by one dominant gene. In this study, BSA (bulked segregant analysis) methods and SSRs (simple sequence repeats) marker polymorphic analysis are used to map the gene. The resistant and susceptible DNA bulks were prepared from the segregating F2 population of the cross between Taichung 29, a susceptible variety as maternal parent, and Chike as paternal parent. Over 400 SSR primers were screened, and five SSR markers Xwmc44, Xgwm259, Xwmc367, Xcfa2292, and Xbarc80 on the chromosome arm 1BL were found to be polymorphic between the resistant and the susceptible DNA bulks as well as their parents. Genetic linkage was tested on segregating F2 population with 200 plants, including 140 resistant and 60 susceptible plants. All the five SSR markers were linked to the stripe rust resistance gene in Chike. The genetic distances for the markers Xwmc44, Xgwm259, Xwmc367, Xcfa2292, and Xbarc80 to the target gene were 8.3 cM, 9.1 cM, 17.2 cM, 20.6 cM, and 31.6 cM, respectively. Analysis using 21 nulli-tetrasomic Chinese Spring lines further confirmed that all the five markers were located on chromosome lB. On the basis of the above results, it is reasonable to assume that the major stripe rust resistance gene YrChk in Chike was located on the chromosome arm 1BL, and its comparison with the other stripe rust resistance genes located on 1B suggested that YrChk may be a novel gene that provides the resistance against stripe rust in Chike. Exploration and utilization of resources of disease resistance genes in native wheat varieties will be helpful both to diversify the resistance genes and to amend the situation of resistance gene simplification in the commercial wheat cultivars in China.
文摘Objective: To observe human to mouse one way mixed lymphocyte(MLC); And to set up the xeno-grats verse host disease Xeno-graft host disease(XGVHD) model,probing its immunologic mechamism.Methods: Mouse splenic lymphocyte were collected in asepsis and treated by mitomycin as activating cell. Human Peripheral blood lymphocytes (hPBL)were separated and gathered as reacting cell; Mouse splenic lymphocyte and hPBL were mixed to incubate for a week. Destroying recipient (mouse) immune system by total body irradiation (TBI) and intraperitoneal injecting CTX、MTX; Separating and collecting hPBL; Injecting hPBL to mouse by caudal vein. Results; ①HPBL in the experiment groups(mixed mouse lymphocyte) proliferated obviously, the amount of 3H-TdR in corporation increased evidently(P<0.05); The mean percentage of CD 4、CD 8、IgG 、IgM positive cells rose markedly. ②Experiment groups,the hPBL were found in the spleen and kidney tissue, fas protein expressing, we occasionally discovered and apoptosis cells.Conclusion: The human to mouse one-way MLC has obvious lymphocyte proliferation. By these means,we succeed in inducing XGVHD and setting up a XGVHD model.