Nitric oxide alleviates oxidative damage induced by high temperature stress in wheat.
Effect of sodium nitroprusside (SNP), a donor of nitric oxide (NO) was examined in two wheat (Triticum aestivum L.) cultivars, C 306 (heat tolerant) and PBW 550 (comparatively heat susceptible) to study the extent of oxidative injury and activities of antioxidant enzyme in relation to high temperature (HT) stress. HT stress resulted in a marked decrease in membrane thermostability (MTS) and 2, 3, 5-triphenyl tetrazolium chloride (TTC) cell viability whereas content of lipid peroxide increased in both the cultivars. The tolerant cultivar C 306 registered less damage to cellular membranes compared to PBW 550 under HT stress. Activities of antioxidant enzymes viz, superoxide dismutase, catalase, ascorbate peroxidase, guaicol peroxidase and glutathione reductase increased with HT in both the cultivars. Following treatment with SNP, activities of all antioxidant enzymes further increased in correspondence with an increase in MTS and TTC. Apparently, lipid peroxide content was reduced by SNP more in shoots of heat tolerant cultivar C 306 indicating better protection over roots under HT stress. The up-regulation of the antioxidant system by NO possibly contributed to better tolerance against HT induced oxidative damage in wheat.
Department of Biochemistry, Punjab Agricultural University, Ludhiana 141 004, Punjab. b.asthir@rediffmail.com
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Shashi
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Navtej
D000975:Antioxidants; D060387:Ascorbate Peroxidases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D005980:Glutathione Reductase / Q000378:metabolism; D006358:Hot Temperature / Q000009:adverse effects*; D006861:Hydrogen Peroxide / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D009569:Nitric Oxide / Q000378:metabolism*; D009599:Nitroprusside / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D018520:Plant Shoots / Q000187:drug effects / Q000254:growth & development; D036226:Seedlings / Q000187:drug effects; D013482:Superoxide Dismutase / Q000378:metabolism; D014908:Triticum / Q000201:enzymology / Q000502:physiology*
D000975:Antioxidants; D009599:Nitroprusside; D009569:Nitric Oxide; D006861:Hydrogen Peroxide; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase