Welz H G, Xia X C, Bassetti P, Melchinger A E, Lübberstedt T
University of Hohenheim, 350 Institute of Plant Breeding, Seed Science and Population Genetics, D-70593, Stuttgart, Germany, DE.
Theor Appl Genet. 1999 Aug;99(3-4):649-55. doi: 10.1007/s001220051280.
Quantitative trait loci (QTLs) for resistance to the fungal pathogen Setosphaeria turcica, the cause of northern corn leaf blight (NCLB), were mapped in a population of 220 F(3) families derived from a cross between two moderately resistant European inbred lines, D32 (dent) and D145 (flint). The population was genotyped with 87 RFLP and 7 SSR markers. Trials were conducted in the field in Switzerland, and in the greenhouse with selected F(3) families in Germany. The F(3) population segregated widely for resistance with transgression of the parents. By composite interval mapping, a total of 13 QTLs were detected with two disease ratings (0 and 3 weeks after flowering). Together these QTLs explained 48% and 62% of the phenotypic variation. Gene action at most QTLs was partially dominant. Eight out of the 13 QTL alleles for resistance were contributed by the more-resistant parent, D145. On chromosomes 3, 5 and 8, QTLs were located in the same chromosomal regions as QTLs in tropical and U.S. Corn Belt germplasm. Some QTLs affected NCLB, head smut and common rust at the same time, with alleles at these loci acting isodirectionally.
对来自两个中度抗病的欧洲自交系D32（马齿型）和D145（硬粒型）杂交产生的220个F(3)家系群体，定位了对引起玉米大斑病（NCLB）的真菌病原体大斑刚毛座腔菌的抗性数量性状位点（QTL）。该群体用87个RFLP和7个SSR标记进行了基因分型。在瑞士的田间以及在德国对选定的F(3)家系进行了温室试验。F(3)群体在抗性方面分离广泛，出现了超亲现象。通过复合区间作图，用两个病情评级（开花后0周和3周）共检测到13个QTL。这些QTL共同解释了48%和62%的表型变异。大多数QTL的基因作用是部分显性的。13个抗性QTL等位基因中有8个来自抗性更强的亲本D145。在第3、5和8号染色体上，QTL位于与热带和美国玉米带种质中的QTL相同的染色体区域。一些QTL同时影响玉米大斑病、丝黑穗病和普通锈病，这些位点的等位基因作用同向。
