Effect of Sulfur Nutrition on Glutathione Content in Sugar Beet Plants in Relation with Aphids Infestation

ZELENA E., ZELENY F, WONISCH A. & TAUSZ M. 2011. Effect of sulfur nutrition on glutathione content in sugar beet plants in relation with aphids infestation. Phyton (Horn, Austria) 50 (2): 319-327, with 3 figures. The effects of sulfur (S) supply combined with nitrogen (N) on plant growth and biosynthesis of glutathione (GSH) in relation with aphids infestation were studied in young sugar beet (Beta vulgaris) plants infested with black bean aphids (Aphis fabae). Both nutrients applied separately stimulated growth of leaves but their effects were amplified when applied together. Single N fertilization enhanced significantly reproduction of aphids, addition of S reduced this effect to about 30 %. The contents of GSH in leaves on variants without S were very low (about 5 nmol/g FW) and manifold increased when S was added (up to about 550 nmol/g FW in middle youngest leaves). Sulfur supplied plants had about 5 times more GSH in youngest leaves than in oldest. The positive effect of S on resistance of plants to aphids manifested itself only in sugar beet supplied with N. We suspect GSH may function in prevention of toxic saliva action of aphids on metabolism of nitrogen in host plant and thus influence the quality of their food.