Lignin, glutathione and kinases play important roles inPaspalum regnelliidefense against spittlebug (Mahanarva spectabilis) attack

Abstract

SummarySpittlebugs cause large production losses that affect agribusiness worldwide. Understanding plant-herbivore interactions at molecular level may be the key to developing resistant cultivars.We assembled ade novotranscriptome for elucidate the roots response from twoPaspalum regnelliigenotypes (BGP 248 and 344) to spittlebug (Mahanarva spectabilis)nymph attack, integrating differential expression analysis and complex network modeling, supplemented by a resistance field experiment and root anatomical analysis.GO terms related to different stress responses were enriched in BGP 248, such as salicylic acid catabolic process, while some specific to spittlebugs like response to herbivores were enriched in BP 344. KEGG enriched pathways were related to structural differences between genotypes, for example, cutin, suberin and wax biosynthesis. BP 344 also presented pathways related to induced defense, such as glutathione metabolism. Metabolic networks highlighted kinases, and coexpression networks demonstrated a greater complexity in their response cascade, which includes lncRNAs.This study provides the first molecular insights into the defense mechanisms ofP. regnelliiagainstM. spectabilis.It was identified that the genotype with the highest nymph mortality (BGP 344) has constitutive barriers, such as lignin, which delay the attack. In addition to presenting a glutathione pathway enriched and greater presence of kinases.