表达Harpin蛋白质Hpa1功能片段的转基因小麦对赤霉病的抗性

来自水稻黄单胞菌的harpin蛋白质Hpa1有促进植物生长、诱导植物抗病性的功能，Hpa1序列10~42氨基酸片段（Hpa1_10-42）的活性比全长分子高1.3~7.5倍。为研究Hpa1_10-42在转基因小麦体内表达以后对赤霉病的影响和评价转基因小麦抗病水平与应用潜力，对6个小麦转基因系进行了测定。结果显示，Hpa1_10-42在转基因系T₃~T₅代呈现稳定表达，用禾谷镰刀菌一个分离物进行接种以后，转基因系发生赤霉病的程度较非转基因小麦显著降低，且转基因系T₃~T₅代赤霉病降低的趋势一致。另外，转基因系小麦病害减轻的程度，与在非转基因小麦上使用杀菌剂的效果相当，表明Hpa1_10-42转基因表达对小麦赤霉病有防治作用。

Transgenic expression of an active fragment of the harpin protein Hpa1 in wheat reduces Fusarium head blight

The harpin protein Hpa1 produced by a bacterial pathogen of rice promotes plant growth and induces disease resistance, and in both effects the 10-42-residue fragment (Hpa1_10-42) isolated from the Hpa1 sequence is 1.3-7.5-fold more effective than the full length. To evaluate possible role of Hpa1_10-42 in wheat resistance to the Fusarium head blight disease, the Hpa1_10-42 gene was transferred into the crop genome, followed by resistance assessments under greenhouse conditions. The independent experiments showed that transgenic expression of Hpa1_10-42 in wheat reduced the disease severity. Six Hpa1_10-42-expressing wheat lines were tested and the expression of Hpa1_10-42 was found to be consistent in T₃-T₅ progenies. Following inoculation with an indigenous F.graminearum isolate, transgenic lines had significantly lower levels of Fusarium head blight compared to non-transformed plants. Reduction of disease severity was consistent in T₃-T₅ progenies of Hpa1_10-42-expressing lines and was equivalent to that in non-transformed plants treated with a fungicide. Therefore, transgenic Hpa1_10-42 expression might provide an effective measure for management of Fusarium head blight in the agriculturally significant crop.