Title: | Arbuscular Mycorrhizal Fungus Alters Alfalfa (Medicago sativa) Defense Enzyme Activities and Volatile Organic Compound Contents in Response to Pea Aphid (Acyrthosiphon pisum) Infestation |
Author(s): | Wang Y; Li Y; Tian Z; Duan T; |
Address: | "State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems, Lanzhou Unviersity, Lanzhou 730020, China. Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Lanzhou 730020, China. College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China. Center for Grassland Microbiome, Lanzhou University, Lanzhou 730000, China" |
ISSN/ISBN: | 2309-608X (Electronic) 2309-608X (Linking) |
Abstract: | "Pea aphid (Acyrthosiphon pisum) infestation leads to withering, reduced yield, and lower quality of the host plant. Arbuscular mycorrhizal (AM) fungi have been found to enhance their host plants' nutrient uptake, growth, and resistance to biotic stresses, including pathogen infection and insect pest infestation. Therefore, we evaluated the effects of AM fungus Rhizophagus intraradices on alfalfa defense responses to pea aphid infestation. Aphid infestation did not affect the colonization of AM fungus. The inoculation of AM fungus, on average, enhanced alfalfa catalase and the contents of salicylic acid and trypsin inhibitor by 101, 9.05, and 7.89% compared with non-mycorrhizal alfalfa, respectively. In addition, polyphenol oxidase activities significantly increased by six-fold after aphid infestation in mycorrhizal alfalfa. Moreover, the fungus significantly (p < 0.05) improved alfalfa shoot N content, net photosynthetic and transpiration rates, and shoot dry weight in aphid infected treatment. The aphid infestation changed the total volatile organic compounds (VOCs) in alfalfa, while AM fungus enhanced the contents of methyl salicylate (MeSA). The co-expression network analysis of differentially expressed genes (DEGs) and differentially expressed VOCs analysis showed that three DEGs, namely MS.gene23894, MS.gene003889, and MS.gene012415, positively correlated with MeSA both in aphid and AM fungus groups. In conclusion, AM fungus increased alfalfa's growth, defense enzyme activities, hormones, and VOCs content and up-regulated VOC-related genes to enhance the alfalfa's resistance following aphid infestation" |
Keywords: | RNA-seq Rhizophagus intraradices alfalfa pea aphid volatile organic compounds; |
Notes: | "PubMed-not-MEDLINEWang, Yajie Li, Yingde Tian, Zhen Duan, Tingyu eng 3207141294/National Natural Science Foundation of China/ Switzerland 2022/12/23 J Fungi (Basel). 2022 Dec 16; 8(12):1308. doi: 10.3390/jof8121308" |