Pottorff Marti O, Li Guojing, Ehlers Jeffery D, Close Timothy J, Roberts Philip A
Department of Botany and Plant Sciences, University of California Riverside, Riverside, CA USA.
Zhejiang Academy of Agricultural Sciences, Hangzhou, People's Republic of China.
Mol Breed. 2014;33(4):779-791. doi: 10.1007/s11032-013-9991-0. Epub 2013 Dec 13.
Fusarium wilt is a vascular disease caused by the fungus f.sp. (Fot) in cowpea [ (L.) Walp]. In this study, we mapped loci conferring resistance to Fot race 4 in three cowpea RIL populations: IT93K-503-1 × CB46, CB27 × 24-125B-1, and CB27 × IT82E-18/Big Buff. Two independent loci which confer resistance to Fot race 4 were identified, - and -. - was identified in the IT93K-503-1 (resistant) × CB46 (susceptible) population and was positioned on the cowpea consensus genetic map, spanning 21.57-29.40 cM on linkage group 5. The - locus was validated by identifying it in both the CB27 (resistant) × 24-125B-1 (susceptible) and CB27 (resistant) × IT82E-18/Big Buff (susceptible) populations. - was positioned on the cowpea consensus genetic map on linkage group 3; the minimum distance spanned 71.52-71.75 cM whereas the maximum distance spanned 64.44-80.23 cM. These genomic locations of - and - on the cowpea consensus genetic map, relative to - which was previously identified as the locus conferring resistance to Fot race 3, established that all three loci were independent. The - and - syntenic loci were examined in , where several disease-resistance candidate genes were identified for both loci. In addition, - and - were coarsely positioned on the cowpea physical map. - and - will contribute to molecular marker development for future use in marker-assisted selection, thereby expediting introgression of Fot race 4 resistance into future cowpea cultivars.
镰刀菌枯萎病是由尖镰孢菌豇豆专化型（Fot）引起的豇豆[（L.）Walp]维管束病害。在本研究中，我们在三个豇豆重组自交系群体中定位了赋予对Fot小种4抗性的基因座：IT93K - 503 - 1×CB46、CB27×24 - 125B - 1和CB27×IT82E - 18/大布法。鉴定出了两个赋予对Fot小种4抗性的独立基因座，即 - 和 - 。 - 在IT93K - 503 - 1（抗病）×CB46（感病）群体中被鉴定出来，并定位在豇豆整合遗传图谱上，位于连锁群5上，跨度为21.57 - 29.40厘摩。 - 基因座在CB27（抗病）×24 - 125B - 1（感病）和CB27（抗病）×IT82E - 18/大布法（感病）群体中均被鉴定出来，从而得到验证。 - 定位在豇豆整合遗传图谱的连锁群3上；最小距离跨度为71.52 - 71.75厘摩，而最大距离跨度为64.44 - 80.23厘摩。 - 和 - 在豇豆整合遗传图谱上的这些基因组位置，相对于之前被鉴定为赋予对Fot小种3抗性的基因座 - ，表明这三个基因座都是独立的。在 - 中检查了 - 和 - 的共线基因座，在其中为这两个基因座鉴定出了几个抗病候选基因。此外， - 和 - 被粗略定位在豇豆物理图谱上。 - 和 - 将有助于开发分子标记，供未来用于标记辅助选择，从而加快将Fot小种4抗性渗入未来的豇豆品种中。
