Phytophthora sojae Kanfman and Gerdemann （P. sojae） is one of the most prevalent pathogens and causes Phytophthora root rot, which limits soybean production worldwide. Development of resistant cultivars is a cost-ef...Phytophthora sojae Kanfman and Gerdemann （P. sojae） is one of the most prevalent pathogens and causes Phytophthora root rot, which limits soybean production worldwide. Development of resistant cultivars is a cost-effective approach to controlling this disease. In this study, 127 soybean germplasm were evaluated for their responses to Phytophthora sojae strain Pm28 using the hypocotyl inoculation technique, and 49 were found resistant to the strain. The hypocotyl of P1, P2, F1, and F2：3 of two crosses of Ludou 4 （resistant）×Youchu 4 （susceptible） and Cangdou 5 （resistant）×Williams （susceptible） were inoculated with Pm28, and were used to analyze the inheritance of resistance. The population derived from the cross of Ludou 4×Youchu 4 was used to map the resistance gene （designated as Rps9） to a linkage group. 932 pairs of SSR primers were used to detect polymorphism, and seven SSR markers were mapped near the resistance gene. The results showed that the resistance to Pm28 in Ludou 4 and Cangdou 5 was controlled by a single dominant gene Rps9, which was located on the molecular linkage group N between the SSR markers Satt631 （7.5 cM） and Sat_186 （4.3 cM）.展开更多
Since oil palm (Elaeis guineensis Jacq.) does not breed true, tissue culture-derived material is the resource of choice for achieving oil palm homogeneity in terms of growth and yield. Currently, no genomic tagging me...Since oil palm (Elaeis guineensis Jacq.) does not breed true, tissue culture-derived material is the resource of choice for achieving oil palm homogeneity in terms of growth and yield. Currently, no genomic tagging method is available with which one could verify the ortet (tissue donor oil palm) from which the clonal planting material (ramets) origi-nated, particularly in cases of unsatisfactory performance. Thus, Sime Darby Plantation used 10 genomic microsatellite markers to genotype 8 sets of 5 ramets +1 ortet and 2 single ortets. The average genetic distance (D) among oil palms from the same set of ramets and ortet was 0.0000 with the exception of sets containing off-type ramets (D = [0.0834 - 0.1505]). The dendrogram showed that the ramets and their ortet of origin formed a sub-cluster, confirming their simi-larity. The 10 microsatellite markers were valuable to Sime Darby as tools for verification of ramet-to-ortet relation-ships and for the identification of off-types. Furthermore, the set of 10 markers revealed a high expected heterozygosity (He = 0.634) that is a high expected heterosis effect on which yield depends.展开更多
基金supported by the Earmarked Fund for Modern Agro-Industry Technology Research System, China (nyhyzx07-053)the Program for Changjiang Scholars and Innovative Research Team in University, China (PCSIRT)the Research Fund for the Doctoral Program of Higher Education of China (20090097120023)
文摘Phytophthora sojae Kanfman and Gerdemann （P. sojae） is one of the most prevalent pathogens and causes Phytophthora root rot, which limits soybean production worldwide. Development of resistant cultivars is a cost-effective approach to controlling this disease. In this study, 127 soybean germplasm were evaluated for their responses to Phytophthora sojae strain Pm28 using the hypocotyl inoculation technique, and 49 were found resistant to the strain. The hypocotyl of P1, P2, F1, and F2：3 of two crosses of Ludou 4 （resistant）×Youchu 4 （susceptible） and Cangdou 5 （resistant）×Williams （susceptible） were inoculated with Pm28, and were used to analyze the inheritance of resistance. The population derived from the cross of Ludou 4×Youchu 4 was used to map the resistance gene （designated as Rps9） to a linkage group. 932 pairs of SSR primers were used to detect polymorphism, and seven SSR markers were mapped near the resistance gene. The results showed that the resistance to Pm28 in Ludou 4 and Cangdou 5 was controlled by a single dominant gene Rps9, which was located on the molecular linkage group N between the SSR markers Satt631 （7.5 cM） and Sat_186 （4.3 cM）.
文摘Since oil palm (Elaeis guineensis Jacq.) does not breed true, tissue culture-derived material is the resource of choice for achieving oil palm homogeneity in terms of growth and yield. Currently, no genomic tagging method is available with which one could verify the ortet (tissue donor oil palm) from which the clonal planting material (ramets) origi-nated, particularly in cases of unsatisfactory performance. Thus, Sime Darby Plantation used 10 genomic microsatellite markers to genotype 8 sets of 5 ramets +1 ortet and 2 single ortets. The average genetic distance (D) among oil palms from the same set of ramets and ortet was 0.0000 with the exception of sets containing off-type ramets (D = [0.0834 - 0.1505]). The dendrogram showed that the ramets and their ortet of origin formed a sub-cluster, confirming their simi-larity. The 10 microsatellite markers were valuable to Sime Darby as tools for verification of ramet-to-ortet relation-ships and for the identification of off-types. Furthermore, the set of 10 markers revealed a high expected heterozygosity (He = 0.634) that is a high expected heterosis effect on which yield depends.
