Discovery of a susceptibility factor for Fusarium head blight on chromosome 7A of wheat
Discovery of a susceptibility factor for Fusarium head blight on chromosome 7A of wheat
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DOI：
10.1007/s00122-021-03825-y
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发表时间：
2021-04-08
影响因子：
5.4
通讯作者：
Rawat, Nidhi
中科院分区：
文献类型：
--
作者：
Chhabra, Bhavit;Tiwari, Vijay;Rawat, Nidhi
位于小麦染色体7A短臂上的一个易感因子的发现和定位，该因子的缺失使植物对枯萎病具有抗性。小麦赤霉病（Fusarium head blight， FHB）是一种由镰刀菌引起的小麦赤霉病。操纵易感因子，即促进疾病发展的植物基因，为增强植物的FHB抗性提供了一种新的替代策略。本研究在7A染色体短臂（7AS）上发现了一个主要影响FHB的易感基因。小麦同源类群7的零体-四体系显示了该基因的剂量效应，其中7A四体比对照中国春小麦更敏感，表明该基因是一个真正的易感因子。5个染色体7A代换系和1个四倍体双粒小麦7A代换系表现出与中国春相似的易感性，表明不同基因型间易感性因子具有共性。该易感因子命名为Sf-Fhb-7AS，并在染色体7AS上定位到del7AS-3和del7AS-8之间的48.5-50.5 Mb的着丝粒周围区域。结果表明，Sf-Fhb-7AS的缺失使小麦对2型赤霉病的抗性增加了50-60%，对其进行调控可以提高小麦对赤霉病的抗性。
Key message Discovery and mapping of a susceptibility factor located on the short arm of wheat chromosome 7A whose deletion makes plants resistant to Fusarium head blight. Fusarium head blight (FHB) disease of wheat caused by Fusarium spp. deteriorates both quantity and quality of the crop. Manipulation of susceptibility factors, the plant genes facilitating disease development, offers a novel and alternative strategy for enhancing FHB resistance in plants. In this study, a major effect susceptibility gene for FHB was identified on the short arm of chromosome 7A (7AS). Nullisomic-tetrasomic lines for homoeologous group-7 of wheat revealed dosage effect of the gene, with tetrasomic 7A being more susceptible than control Chinese Spring wheat, qualifying it as a genuine susceptibility factor. Five chromosome 7A inter-varietal substitution lines and a tetraploid Triticum dicoccoides 7A substitution line showed similar susceptibility as that of Chinese Spring, indicating toward the commonality of the susceptibility factor among these diverse genotypes. The susceptibility factor was named as Sf-Fhb-7AS and mapped on chromosome 7AS to a 48.5-50.5 Mb peri-centromeric region between del7AS-3 and del7AS-8. Our results showed that deletion of Sf-Fhb-7AS imparts 50-60% type 2 FHB resistance and its manipulation can be used to enhance resistance against FHB in wheat.