Professor Fayetteville State University Fayetteville, North Carolina
Heat stress compromises wheat resistance to Hessian fly (HF, Mayetiola destructor) infestation. The objective of this research is to analyze the molecular basis of heat-induced loss of wheat resistance to HF infestation using RNA Sequencing (RNA-seq). To this end, two resistant near-isogenic wheat cultivars ‘Molly’ and ‘Caldwell’ containing the resistance genes H13 and H6, respectively, were subjected to heat stress to determine its impact on wheat – HF interactions phenotypically and genetically. Our results indicate that heat stress down-regulate most genes involved in primary metabolism and biosynthesis of lignin and cuticular wax, but up-regulate most or all genes involved in auxin and 12-oxo-phytodienoic acid (OPDA) signaling pathways. Our results and previous reports suggest that heat stress may impair the processes in wheat plants that produce and mobilize chemical resources needed for synthesizing defensive compounds, weaken cell wall and cuticle defense, decrease OPDA signaling, but increase auxin signaling, leading to the suppressed resistance and activation of susceptibility.
