Department of Plant Pathology, College of Plant Protection, Biological Control Center for Plant Diseases and Plant Pests of Hebei, Hebei Agricultural University, 289 Lingyusi Street, Baoding, Hebei, China.
Theor Appl Genet. 2013 Aug;126(8):2141-7. doi: 10.1007/s00122-013-2124-7. Epub 2013 May 21.
Neijiang 977671 and 19 near-isogenic lines with known leaf rust resistance genes were inoculated with 12 pathotypes of Puccinia triticina for postulation of leaf rust resistance genes effective at the seedling stage. The reaction pattern of Neijiang 977671 differed from those of the lines with known leaf rust resistance genes used in the test, indicating that Neijiang 977671 may carry a new leaf rust resistance gene(s). With the objective of identifying and mapping the new gene for resistance to leaf rust, F1 and F2 plants, and F2:3 families, from Neijiang 977671 × Zhengzhou 5389 (susceptible) were inoculated with Chinese P. triticina pathotype FHNQ in the greenhouse. Results from the F2 and F2:3 populations indicated that a single dominant gene, temporarily designated LrNJ97, conferred resistance. In order to identify other possible genes in Neijiang 977671 other eight P. triticina pathotypes avirulent on Neijiang 977671 were used to inoculate 25 F2:3 families. The results showed that at least three leaf rust resistance genes were deduced in Neijiang 977671. Bulked segregant analysis was performed on equal amounts of genomic DNA from 20 resistant and 20 susceptible F2 plants. SSR markers polymorphic between the resistant and susceptible bulks were used to analyze the F2:3 families. LrNJ97 was linked to five SSR loci on chromosome 2BL. The two closest flanking SSR loci were Xwmc317 and Xbarc159 at genetic distances of 4.2 and 2.2 cM, respectively. At present two designated genes (Lr50 and Lr58) are located on chromosome 2BL. In the seedling tests, the reaction pattern of LrNJ97 was different from that of Lr50. Lr50 and Lr58 were derived from T. armeniacum and Ae. triuncialis, respectively, whereas according to the pedigree of Neijiang 977671 LrNJ97 is from common wheat. Although seeds of lines with Lr58 were not available, it was concluded that LrNJ97 is likely to be a new leaf rust resistance gene.
内江 977671 和 19 个近等基因系具有已知的抗叶锈病基因，用 12 个小麦叶锈菌生理小种接种，以预测苗期抗叶锈病基因的有效性。内江 977671 的反应模式与试验中使用的具有已知抗叶锈病基因的系不同，表明内江 977671 可能携带新的抗叶锈病基因。为了鉴定和定位内江 977671 抗叶锈病的新基因，内江 977671×郑麦 5389（感病）的 F1 和 F2 植株及 F2：3 家系用温室中的中国小麦叶锈菌生理小种 FHNQ 接种。F2 和 F2：3 群体的结果表明，一个单一的显性基因，暂时命名为 LrNJ97，赋予了抗性。为了鉴定内江 977671 中的其他可能基因，还使用 8 个对内江 977671 无毒的小麦叶锈菌生理小种接种 25 个 F2：3 家系。结果表明，内江 977671 中至少有 3 个抗叶锈病基因。用 20 个抗性和 20 个敏感 F2 植株等量的基因组 DNA 进行了混池分离分析。用抗性和敏感混池之间多态性的 SSR 标记分析了 F2：3 家系。LrNJ97 与染色体 2BL 上的 5 个 SSR 位点连锁。两个最接近的侧翼 SSR 标记是 Xwmc317 和 Xbarc159，遗传距离分别为 4.2 和 2.2cM。目前，两个指定的基因（Lr50 和 Lr58）位于 2BL 染色体上。在苗期试验中，LrNJ97 的反应模式与 Lr50 不同。Lr50 和 Lr58 分别来自于华山新麦草和节节麦，而根据内江 977671 的系谱，LrNJ97 来自普通小麦。虽然没有 Lr58 系的种子，但可以推断 LrNJ97 可能是一个新的抗叶锈病基因。
