Host‐induced gene silencing of an important pathogenicity factor P s CPK 1 in Puccinia striiformis f. sp. tritici enhances resistance of wheat to stripe rust

作者：Tuo Qi, Xiaoguo Zhu, Chenlong Tan, Peng Liu, Jia Guo, Jia Guo, Zhensheng Kang, Jun Guo, Jun Guo · 发表于：Plant Biotechnology Journal · 年份：2017 · DOI：10.1111/pbi.12829 · 被引用次数：134 · 研究领域：Wheat and Barley Genetics and Pathology、Plant-Microbe Interactions and Immunity、Plant Virus Research Studies

Summary Rust fungi are devastating plant pathogens and cause a large economic impact on wheat production worldwide. To overcome this rapid loss of resistance in varieties, we generated stable transgenic wheat plants expressing short interfering RNAs (siRNAs) targeting potentially vital genes of Puccinia striiformis f. sp. tritici (Pst). Protein kinase A (PKA) has been proved to play important roles in regulating the virulence of phytopathogenic fungi. PsCPK1, a PKA catalytic subunit gene from Pst, is highly induced at the early infection stage of Pst. The instantaneous silencing of PsCPK1 by barley stripe mosaic virus (BSMV)‐mediated host‐induced gene silencing (HIGS) results in a significant reduction in the length of infection hyphae and disease phenotype. These results indicate that PsCPK1 is an important pathogenicity factor by regulating Pst growth and development. Two transgenic lines expressing the RNA interference (RNAi) construct in a normally susceptible wheat cultivar displayed high levels of stable and consistent resistance to Pst throughout the T3 to T4 generations. The presence of the interfering RNAs in transgenic wheat plants was confirmed by northern blotting, and these RNAs were found to efficiently down‐regulate PsCPK1 expression in wheat. This study addresses important aspects for the development of fungal‐derived resistance through the expression of silencing constructs in host plants as a powerful strategy to control cereal rust diseases.