Chèvre A-M, Brun H, Eber F, Letanneur J-C, Vallee P, Ermel M, Glais I, Li Hua, Sivasithamparam K, Barbetti M J
INRA, UMR118, F-35000 Rennes, France.
INRA, UMR1099, F-35000 Rennes, France.
Plant Dis. 2008 Aug;92(8):1208-1214. doi: 10.1094/PDIS-92-8-1208.
The value of Katanning Early Maturing (KEM) breeding lines from Western Australia, derived from Brassica napus × B. juncea crosses, was assessed as a source of germplasm for resistance to blackleg disease (caused by Leptosphaeria maculans) in spring-type oilseed rape cultivars. The stability of blackleg resistance in these KEM lines was related to key cytological characteristics to determine why there are poor levels of introgression of this resistance into progeny. Promising recombinant KEM lines were crossed with the spring-type B. napus cv. Dunkeld, which has useful polygenic resistance to blackleg, and screened for resistance. The lines were analyzed cytologically for pairing of bivalents in each generation to aid in the selection of stable recombinant lines. KEM recombinant lines showing regular meiotic behavior and a high level of blackleg resistance were obtained for the first time. We also showed that the stable introgression of the B. juncea resistance from the KEM lines into a 'Dunkeld' background was possible. Inoculation of selfing and backcross populations with isolates of L. maculans having different AvrLm genes indicated that the B. juncea resistance gene, Rlm6, had been introgressed into a B. napus spring-type cultivar carrying polygenic resistance. The combination of both resistances would enhance the overall effectiveness of resistance against L. maculans. This is clearly needed in Australia and France where cultivars relying upon single dominant gene-based resistance for their effectiveness have proved not durable.
对源自西澳大利亚的卡坦宁早熟（KEM）育种系（由甘蓝型油菜×芥菜型油菜杂交而来）进行了评估，以确定其作为春性型油菜品种抗黑胫病（由大斑壳二孢引起）种质资源的价值。这些KEM系中黑胫病抗性的稳定性与关键细胞学特征相关，以确定为何这种抗性在后代中的渗入水平较低。将有前景的重组KEM系与具有有用多基因黑胫病抗性的春性型甘蓝型油菜品种敦卡德杂交，并进行抗性筛选。对各代的二价体配对情况进行细胞学分析，以辅助筛选稳定的重组系。首次获得了表现出正常减数分裂行为且具有高水平黑胫病抗性的KEM重组系。我们还表明，将KEM系中的芥菜型油菜抗性稳定渗入到“敦卡德”背景中是可行的。用具有不同AvrLm基因的大斑壳二孢分离株接种自交和回交群体，结果表明芥菜型油菜抗性基因Rlm6已渗入到携带多基因抗性的春性型甘蓝型油菜品种中。两种抗性的组合将增强对大斑壳二孢抗性的整体有效性。在澳大利亚和法国显然需要这样做，因为依赖单一显性基因抗性的品种已被证明其抗性不持久。
