Transcriptomic and volatile signatures associated with maize defense against corn leaf aphid

Authors

Lise Pingault, University of Nebraska-LincolnFollow
Suresh Varsani, University of Nebraska - LincolnFollow
Nathan Palmer, USDA ARSFollow
Swayamjit Ray, Pennsylvania State UniversityFollow
W. Paul Williams, USDA-ARS, Mississippi State, MSFollow
Dawn S. Luthe, Pennsylvania State UniversityFollow
Jared G. Ali, Pennsylvania State UniversityFollow
Gautam Sarath, United States Department of Agriculture -Agricultural Research ServiceFollow
Joe Louis, University of Nebraska–LincolnFollow

Date of this Version

2021

Citation

Pingault et al. BMC Plant Biology (2021) 21:138

https://doi.org/10.1186/s12870-021-02910-0

Comments

© The Author(s). 2021 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License

Abstract

Background: Maize (Zea mays L.) is a major cereal crop, with the United States accounting for over 40% of the worldwide production. Corn leaf aphid [CLA; Rhopalosiphum maidis (Fitch)] is an economically important pest of maize and several other monocot crops. In addition to feeding damage, CLA acts as a vector for viruses that cause devastating diseases in maize. We have shown previously that the maize inbred line Mp708, which was developed by classical plant breeding, provides heightened resistance to CLA. However, the transcriptomic variation conferring CLA resistance to Mp708 has not been investigated.

Results: In this study, we contrasted the defense responses of the resistant Mp708 genotype to those of the susceptible Tx601 genotype at the transcriptomic (mRNA-seq) and volatile blend levels. Our results suggest that there was a greater transcriptomic remodeling in Mp708 plants in response to CLA infestation compared to the Tx601 plants. These transcriptomic signatures indicated an activation of hormonal pathways, and regulation of sesquiterpenes and terpenoid synthases in a constitutive and inducible manner. Transcriptomic analysis also revealed that the resistant Mp708 genotype possessed distinct regulation of ethylene and jasmonic acid pathways before and after aphid infestation. Finally, our results also highlight the significance of constitutive production of volatile organic compounds (VOCs) in Mp708 and Tx601 plants that may contribute to maize direct and/or indirect defense responses.

Conclusions: This study provided further insights to understand the role of defense signaling networks in Mp708’s resistance to CLA.