Arthropod-Plant Interactions

, Volume 12, Issue 4, pp 575–589 | Cite as

Herbivore- and MeJA-induced volatile emissions from the redroot pigweed Amaranthus retroflexus Linnaeus: their roles in attracting Microplitis mediator (Haliday) parasitoids

  • Huilin Yu
  • Yongjun Zhang
  • Yunhe Li
  • Ziyun Lu
  • Xiangju Li
Original Paper


The redroot pigweed Amaranthus retroflexus Linnaeus (Caryophyllales: Amaranthaceae), an annual weed, is a host plant of the cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Microplitis mediator (Haliday) (Hymenoptera: Braconidae) is a parasitoid of H. armigera. Here, the electrophysiological and behavioral responses of M. mediator to induced redroot pigweed volatiles were investigated. Female parasitoids were significantly attracted to odors from plants induced by H. armigera damage, H. armigera continuous feeding, and 10 mM methyl jasmonate (MeJA) spray. The gas chromatography–mass spectrometry (GC–MS) results demonstrated that there were significant changes in volatiles from these three treatments in comparison with the control. When the constitutive compound 6-methyl-5-hepten-2-one was emitted in significant amounts from treated plants, it could elicit a medium electrophysiological response (0.2 ≤ value < 0.8) , a significant behavioral response of M. mediator females. β-Elemene, emitted from two treatments (plants damaged by H. armigera, plants with H. armigera continuous feeding), showed a very weak electrophysiological response (value < 0.2), but was significantly attractive to M. mediator. The results showed that 6-methyl-5-hepten-2-one and β-elemene might play important roles in mediating the foraging behavior of M. mediator. Further work will be conducted to evaluate the function of these two compounds under semi-field and field conditions and exploit them as attractants for M. mediator to control H. armigera.


Redroot pigweed Volatile Microplitis mediator Behavioral response 



We thank Yao Xiao (Northwest A&F University, China) for cultivating the Amaranthus retroflexus, and we thank Yafeng Xiao (Hubei Engineering University, China) and Yunfa Zhang (Hubei vocational college of Bio-Technology, China) for helping to breed the parasitoids. We would like to extend special thanks to Zhiying Hun (Plant Protection Institute, Hebei Academy of Agricultural and Forestry Sciences, China) for providing the Amaranthus retroflexus seeds. This study was supported by the National Natural Science Foundation of China (No. 31201524).

Supplementary material

11829_2018_9606_MOESM1_ESM.docx (20 kb)
Supplementary material 1 (DOCX 19 KB)


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Authors and Affiliations

  1. 1.State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingPeople’s Republic of China
  2. 2.Institute of Plant ProtectionHebei Academy of Agriculture and ForestryBaodingPeople’s Republic of China

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