Studies on effects of salicylic acid and thiourea on biochemical activities and yield production in wheat (Triticum aestivum var. Gimaza 9) plants grown under drought stress

Abstract

Drought is a problem of water deficit in the soil. It causes restrictions of wheat plants growth and productivity. In the present approach, we explored new methods for drought managment. Wheat grains were presoaked in ~1 mmol salicylic acid (SA). Wheat was left to grow with 40% soil water holding capacity in pots until yielding stages. The leaves which were produced were two-times sprayed with 2.5 and 5 mmol thiourea (Th) before anthesis. Morphological and biochemical traits were analyzed on the heading stage in addition to yield and yield components. Results show a conspicuous anti-drought effect in pretreated-compared to untreated-wheat. For example, pretreated wheat with SA and/or Th, possessed a significant increase in carotenoids, antioxidant enzymes activities and some metabolites (growth promotors, photosynthetic pigments, carbohydrates, nitrogenous constituents and minerals). On the contrary, lipid peroxidation and H 2 O 2 decreased in level under the effect of external treatments. Wheat general morphology and yield components were generally improved upon SA and/or Th pretreatments. These data reinforced further investigations to reveal the reason behind the anti-drought responses in treated wheat with low doses of SA and/or Th before and during exposure to a progressive drought. Keywords: Biochemical activity, foliar application, salicylic acid, thiourea, wheat