Co-transcriptomic analysis of the maize-western corn rootworm interaction

Authors: PINGAULT, LISE - University Of Nebraska; BASU, SAUMIK - University Of Nebraska; VELLICHIRAMMAL, NEETHA - University Of Nebraska; Williams, William; Sarath, Gautam; LOUIS, JOE - University Of Nebraska

Submitted to: Plants
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/31/2022
Publication Date: 9/7/2022
Citation: Pingault, L., Basu, S., Vellichirammal, N.N., Williams, W.P., Sarath, G., Louis, J. 2022. Co-transcriptomic analysis of the maize-western corn rootworm interaction. Plants. https://doi.org/10.3390/plants11182335.
DOI: https://doi.org/10.3390/plants11182335

Interpretive Summary: Plants can be attacked by aboveground and belowground pests. How attack by these different pests modulate plant defense and how feeding on the plant changes insect physiology are critical to developing sustainable plant resistance over the long term. Using a broadly resistant maize line, Mp708, and the root feeding Western Corn Rootworm (WCR) the molecular changes occurring in plant tissues and the WCR were investigated. Plant defense genes were elevated in expression in both the roots and shoots five days after WCR infestation, whereas insect defense genes were lowered in expression. These data highlight the dynamic effects that herbivory by WCR on Mp708 plants has on both insect and plant. The data also indicate a path forward to evaluate traits that can provide defense against WCR, and conversely potential targets in WCR that can reduce insect pestilence.

Technical Abstract: The Western Corn Rootworm (WCR; Diabrotica virgifera virgifera) is an economically important belowground pest of maize. Belowground feeding by WCR is damaging because it weakens the roots system, diminishes nutrient uptake, and creates entry points for fungal and bacterial pathogens and increases lodging, all of which can significantly suppress maize yields. Previously, it was demonstrated that belowground herbivory can trigger plant defense responses in the roots and the shoots, thereby impacting intraplant communication. Although several aspects of maize-WCR interactions have been reported, co-transcriptomic remodeling in the plant and insect are yet to be explored. We used a maize genotype, Mp708, that is resistant to a large guild of herbivore pests to study the underlying plant defense signaling network between below and aboveground tissues. We also evaluated WCR compensatory transcriptome responses. Using RNA-seq, we profiled the transcriptome of roots and leaves that interacted with WCR infestation up to 5 days post infestation (dpi). Our results suggest that several plant defense genes were induced in roots, whereas WCR defense genes were downregulated at 5 dpi. These findings indicate a dynamic transcriptomic dialog between WCR and infested maize plants.