Two fragments SCS362o and SCS3580 of the co-dominant marker OPS0362o&580 that were linked to the resistance gene of soybean frog-eye leaf spot have been completely sequenced. A significant insertion of 30 bp is th...Two fragments SCS362o and SCS3580 of the co-dominant marker OPS0362o&580 that were linked to the resistance gene of soybean frog-eye leaf spot have been completely sequenced. A significant insertion of 30 bp is the main reason of the polymorphism between the two fragments. The results of Southern hybridization indicate that SCS362o derives from a single- or low-copy sequence and can be used as an RFLP probe. A co-dominant SCAR marker SCSSeao&sao has been developed based on the sequences. The segregation of SCS362o&58o is similar to that of RAPD marker OPS03620&580. Significant polymorphism has been shown between resistant and susceptible genotypes when 62 soybean genotypes were surveyed for the SCAR marker. Therefore, the marker can be used in the resistance breeding of soybean frog-eye leaf spot by marker-assisted selection.展开更多
Frog-eye leaf spot of soybean caused by Cercospora sojina Hara is a kind of worldwide disease. Resistance to race 7 of C. sojina was found to be due to a single dominant gene through analyzing resistant behavior of th...Frog-eye leaf spot of soybean caused by Cercospora sojina Hara is a kind of worldwide disease. Resistance to race 7 of C. sojina was found to be due to a single dominant gene through analyzing resistant behavior of the cross NEAU91212 （susceptible to race 7）× NEAU9674 （resistant to all races）. 3 RAPD markers linked to the resistant gene Rcsc 7 were identified using the BSA method. 2 fragments of OPS03<sub>620</sub> and OPS03<sub>580</sub> amplified with primer OPS03 co-dominantly segregated in the F<sub>2</sub> individuals. The genetic distance between OPS03<sub>620</sub> and the resistant gene is 8.7 cM. According to the co-dominant marker, the accuracy of predicting the homozygous and heterozygous resistant F<sub>2</sub> individuals were 100% and 97.6%, respectively.展开更多
Cerospora sojina Hara. toxin produced by mycelia of the pathogen can harm soybean plants. In this paper, 50 varieties and one resistant-susceptible combination were used to study the toxin resistance and it's inhe...Cerospora sojina Hara. toxin produced by mycelia of the pathogen can harm soybean plants. In this paper, 50 varieties and one resistant-susceptible combination were used to study the toxin resistance and it's inheritance. Comparing the results from the field under different inoculation conditions, the average coincidence rate of the toxin test is 62.37%. The inheritance of resistance to the toxin of Race 7 of Cerospora sojina Hara was proved to be controlled by a pair of single dominant genes. The toxin appraisal method can be used for many purposes owing to it's convenience.展开更多
Late-cycle diseases (LCD) cause a significant deterioration in quality and reduce yields in soybean crops. In Argentina, in particular, leaf blight and purple seed stain, caused by the agent Cercospora kikuchii, and f...Late-cycle diseases (LCD) cause a significant deterioration in quality and reduce yields in soybean crops. In Argentina, in particular, leaf blight and purple seed stain, caused by the agent Cercospora kikuchii, and frog eye spot, caused by C. sojina, are the prevailing sources of diseases. The early, rapid and accurate detection of these phytopathogens becomes essential, and would contribute to preserving both the environment and the health of humans and animals by preventing the wasteful or improper use of chemicals such as pesticides. In order to detect Cercospora species in soybean plants at an early stage, immunochemical and molecular techniques were developed in this work. Strains from the NITE Biological Resource Center collection (Japan): Cercospora kikuchii NBRC 6711 and Cercospora sojina NBRC 6715 and regional isolates of C. kikuchii were used. To develop Dot-Blot and PCR techniques, experiments with plants undergoing different treatments were carried out: those experimentally inoculated with these fungi, those treated with sterile water and healthy plants as well. Both techniques allowed the detection, at early stages, of Cercospora species involved in two of the most frequent LCD in the country, when the cercosporin concentration produced by the fungus was higher than 3.93 ± 0.39 nmol·cyl-1 ±SD. The sensitivity between both techniques was very different. While Dot-Blot allowed the detection of the disease 4 days after inoculation, PCR detected it after 4 hours, even without visible symptoms of the disease.展开更多
文摘Two fragments SCS362o and SCS3580 of the co-dominant marker OPS0362o&580 that were linked to the resistance gene of soybean frog-eye leaf spot have been completely sequenced. A significant insertion of 30 bp is the main reason of the polymorphism between the two fragments. The results of Southern hybridization indicate that SCS362o derives from a single- or low-copy sequence and can be used as an RFLP probe. A co-dominant SCAR marker SCSSeao&sao has been developed based on the sequences. The segregation of SCS362o&58o is similar to that of RAPD marker OPS03620&580. Significant polymorphism has been shown between resistant and susceptible genotypes when 62 soybean genotypes were surveyed for the SCAR marker. Therefore, the marker can be used in the resistance breeding of soybean frog-eye leaf spot by marker-assisted selection.
文摘Frog-eye leaf spot of soybean caused by Cercospora sojina Hara is a kind of worldwide disease. Resistance to race 7 of C. sojina was found to be due to a single dominant gene through analyzing resistant behavior of the cross NEAU91212 （susceptible to race 7）× NEAU9674 （resistant to all races）. 3 RAPD markers linked to the resistant gene Rcsc 7 were identified using the BSA method. 2 fragments of OPS03<sub>620</sub> and OPS03<sub>580</sub> amplified with primer OPS03 co-dominantly segregated in the F<sub>2</sub> individuals. The genetic distance between OPS03<sub>620</sub> and the resistant gene is 8.7 cM. According to the co-dominant marker, the accuracy of predicting the homozygous and heterozygous resistant F<sub>2</sub> individuals were 100% and 97.6%, respectively.
文摘Cerospora sojina Hara. toxin produced by mycelia of the pathogen can harm soybean plants. In this paper, 50 varieties and one resistant-susceptible combination were used to study the toxin resistance and it's inheritance. Comparing the results from the field under different inoculation conditions, the average coincidence rate of the toxin test is 62.37%. The inheritance of resistance to the toxin of Race 7 of Cerospora sojina Hara was proved to be controlled by a pair of single dominant genes. The toxin appraisal method can be used for many purposes owing to it's convenience.
文摘Late-cycle diseases (LCD) cause a significant deterioration in quality and reduce yields in soybean crops. In Argentina, in particular, leaf blight and purple seed stain, caused by the agent Cercospora kikuchii, and frog eye spot, caused by C. sojina, are the prevailing sources of diseases. The early, rapid and accurate detection of these phytopathogens becomes essential, and would contribute to preserving both the environment and the health of humans and animals by preventing the wasteful or improper use of chemicals such as pesticides. In order to detect Cercospora species in soybean plants at an early stage, immunochemical and molecular techniques were developed in this work. Strains from the NITE Biological Resource Center collection (Japan): Cercospora kikuchii NBRC 6711 and Cercospora sojina NBRC 6715 and regional isolates of C. kikuchii were used. To develop Dot-Blot and PCR techniques, experiments with plants undergoing different treatments were carried out: those experimentally inoculated with these fungi, those treated with sterile water and healthy plants as well. Both techniques allowed the detection, at early stages, of Cercospora species involved in two of the most frequent LCD in the country, when the cercosporin concentration produced by the fungus was higher than 3.93 ± 0.39 nmol·cyl-1 ±SD. The sensitivity between both techniques was very different. While Dot-Blot allowed the detection of the disease 4 days after inoculation, PCR detected it after 4 hours, even without visible symptoms of the disease.
