Abstract
The present investigation reports the activities of different antioxidant enzymes and invertases (acid, alkaline and cell wall bound) in shoots and roots of 5.5-day-old seedlings of wheat cultivars PBW 644 (drought tolerant and ABA higher sensitive) and PBW 343 (drought susceptible and ABA lesser sensitive) under ABA and water-deficit stress in the presence of H2O2/nitric oxide (NO) donors as well as scavengers. Drought stress was produced by 20% PEG 6000. Sodium nitroprusside as NO donor and dimethylthiourea and 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO) as H2O2 and NO scavengers, respectively, were used. Roots of PBW 644 increased activities of antioxidant enzymes and invertases (acid and alkaline) and sucrose content, while PBW 343 decreased these under PEG. This was related to the presence of endogenous H2O2/NO regulation of these parameters under PEG in roots of PBW 644 but deficient in roots of PBW 343 but improved under exogenous H2O2/NO for some parameters. However, compared to PEG, roots of PBW 343 showed endogenous H2O2/NO regulation of many these parameters under ABA. Under ABA, endogenous H2O2/NO regulation was comparable between cultivars. This study showed that H2O2/NO signalling plays an important role in drought tolerance by upregulating antioxidant enzymes and invertases under stress. ABA sensitivity level and ABA levels present in cells may help to produce an effective endogenous H2O2/NO signalling.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call