LAUSR

Molybdenum (Mo), an essential microelement for plant growth, plays important roles in multiple metabolic and physiological processes, including wheat responses to drought and cold stress. Lipids also have crucial roles in plant adaption to abiotic stress. This study was undertaken to determine the Mo-induced lipid changes associated with Mo-enhanced drought tolerance in wheat using glycerolipidomic and transcriptomic analyses. Mo treatments increased transcript level of genes involved in fatty acid and glycerolipid biosynthesis and desaturation, but suppressed the expression of genes in oxylipin production in wheat. Wheat plants supplemented with Mo displayed higher content of monogalactosyldiacyglycerol (MGDG), digalactosyldoacylglycerol (DGDG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE) and phosphatidylcholine (PC) with increased unsaturation. The level of MGDG, DGDG, PC and PG increased under polyethylene glycol 6000-simulated drought stress (PSD), with varied magnitudes in the presence and absence of Mo. Mo increased accumulations of the most abundant glycerolipids species of C36:6, C34:4, C34:3 by increasing gene expressions of desaturation under PSD, which contributed to maintaining fluidity of membranes. In addition, Mo attenuated the decrease in DGDG/MGDG and PC/PE ratios under simulated drought. Those lipid changes in Mo-treated wheat would contribute to maintaining the integrity of membranes and protecting photosynthetic apparatus, together enhancing drought tolerance of wheat.