Impact of transient heat stress on polar lipid metabolisms of wheat near-isogenic lines contrasting in Hessian fly resistance
Transient heat-stress may compromise resistance of wheat plants to Hessian fly [Mayetiola destructor (Say)] infestation. In this research, we applied heat stress of 40ºC on two wheat (Triticum aestivum L) near-isogenic lines), Molly (Resistant to Hessian fly) and Newton (Susceptible to Hessian fly) for 6 h after initiation of Hessian fly larval attacks. We determined polar lipid profiles of each treatment using an automated electrospray ionization-tandem mass spectrometry (ESI-MS/MS) analysis. Heat stress, alone or in combination with infestation, caused significant reduction in the content of total polar lipid and double bond index (DBI). Heat stress caused similar changes in lipid profiles between Molly and Newton, but infestation induced more diverse changes between these lines. The combination of heat and infestation generated unique lipid profiles and exerted greater impact on lipid metabolism than heat stress or infestation alone. Our results suggest that changes in lipid metabolism caused by heat stress may be part of the metabolic pathways through which heat stress suppress resistance of wheat plants to Hessian fly infestation.
Key words: Heat stress, infestation, lipid metabolism, wheat, Hessian fly