Heterografting enhances chrysanthemum resistance to Alternaria alternata via jasmonate-mediated increases in trichomes and terpenoids

作者：Wenjie Li, Qingling Zhan, Yunxiao Guan, Likai Wang, Li Song, Shanhu Zheng, Hongyu Ma, Ye Liu, Lian Ding, Shuang Zhao, Zhenxing Wang, Jiafu Jiang, Weimin Fang, Fadi Chen, Sumei Chen, Zhiyong Guan · 发表于：Journal of Experimental Botany · 年份：2024 · DOI：10.1093/jxb/erae212 · 被引用次数：13 · 研究领域：Fungal Plant Pathogen Control、Nematode management and characterization studies、Plant-Microbe Interactions and Immunity

Trichomes are specialized hair-like structures in the epidermal cells of the above-ground parts of plants and help to protect them from pests and pathogens, and produce valuable metabolites. Chrysanthemum morifolium, which is used in tea products, has both ornamental and medicinal value; however, it is susceptible to infection by the fungus Alternaria alternata, which can result in substantial economic losses. Increasing the density of glandular trichomes enhances disease resistance and improves the production of medicinal metabolites in chrysanthemums, and jasmonate (JA) is known to promote the formation of trichomes in various plants. However, it remains unclear whether glandular trichomes in chrysanthemums are regulated by JA. In addition, grafting, a technique that can improve plant resistance to biotic stresses, has been poorly examined for its impact on glandular trichomes, terpenoids, and disease resistance. In this study, we demonstrate that grafting with Artemisia vulgaris rootstocks improves the resistance of chrysanthemum scions to A. alternata. Heterografted chrysanthemums exhibited higher trichome density and terpenoid content compared to self-grafted counterparts. Transcriptome analysis highlighted the significant role of CmJAZ1-like in disease resistance in heterografted chrysanthemums. Lines overexpressing CmJAZ1-like exhibited sensitivity to A. alternata, and this was characterized by reduced glandular trichome density and limited terpenoid content. Conversel...