Abiotic stresses impact growth, development, and productivity, and significantly limit the global agricultural productivity mainly by impairing cellular physiology/biochemistry via elevating reactive oxygen species (ROS) generation. If not metabolized, ROS (such as O2 (•-), OH(•), H2O2, or (1)O2) exceeds the status of antioxidants and cause damage to DNA, proteins, lipids, and other macromolecules, and finally cellular metabolism arrest. Plants are endowed with a family of enzymes called superoxide dismutases (SODs) that protects cells against potential consequences caused by cytotoxic O2 (•-) by catalyzing its conversion to O2 and H2O2. Hence, SODs constitute the first line of defense against abiotic stress-accrued enhanced ROS and its reaction products. In the light of recent reports, the present effort: (a) overviews abiotic stresses, ROS, and their metabolism; (b) introduces and discusses SODs and their types, significance, and appraises abiotic stress-mediated modulation in plants; (c) analyzes major reports available on genetic engineering of SODs in plants; and finally, (d) highlights major aspects so far least studied in the current context. Literature appraised herein reflects clear information paucity in context with the molecular/genetic insights into the major functions (and underlying mechanisms) performed by SODs, and also with the regulation of SODs by post-translational modifications. If the previous aspects are considered in the future works, the outcome can be significant in sustainably improving plant abiotic stress tolerance and efficiently managing agricultural challenges under changing climatic conditions.

The present experiment was carried out to evaluate the effects of vitamin E and C supplementation on the antioxidant status of broiler breeder hens during summer. Two hundred seventy broiler breeder birds (coloured) were divided into nine groups with three replicates having 10 birds in each, and were supplemented two levels of antioxidant vitamins E (250 mg or 500 mg/kg) or C (200 mg or 400 mg/kg) alone or in combinations for a period of 8 weeks. All the vitamin supplemented groups showed significantly lowered malondialdehyde (MDA) level, higher activities of superoxide dismutase (SOD), catalase (CAT) enzymes and higher Ferric Reducing Antioxidant Power (FRAP) activities in erythrocytes than control. However, supplementation with combination of vitamins proved to be better than individual supplementation. It could be concluded that the combination of vitamins C and E at lower level (@ 200 mg/kg and 250 mg/kg, respectively) had higher erythrocytic antioxidant status in coloured broiler breeder hens as compared to individual vitamin supplementation during hot and humid stress.

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