Abstract
Anthropogenic activities such as mining, fossil fuel combustion, fertilisers and pesticides utilisation in agriculture, metallurgic processes and disposal of industrial wastes have contributed an exponential rise in arsenic content in environment. The present paper deals with arsenate (AsV) incited stress in chickpea (Cicer arietinum L.) plants and its alleviation through the application of nitric oxide (NO) and spermidine (SPD). The exposure of C. arietinum to AsV reduced seedling length, biomass, relative water content and biochemical constituents. All the above-mentioned parameters were escalated when sodium nitroprusside (SNP) or SPD were utilised alone or in combination with AsV. The electrolyte leakage and malondialdehyde content were increased in chickpea treated with AsV, but reduced in combine treatment (As + SNP + SPD). In chickpea seedlings, 89.4, 248.4 and 333.3% stimulation were recorded in sugar, proline and glycine betaine contents, respectively, with As + SNP + SPD treatment in comparison to control. SNP and SPD modulated function of glyoxalase enzymes by which methylglyoxal (MG) was significantly detoxified in C. arietinum. Maximum reduction 45.2% was observed in MG content in SNP + SPD treatment over AsV stress. Hence, synergistic application of NO and SPD protected chickpea plants against AsV-generated stress by strengthening the antioxidant defence and glyoxalase system, which helped in regulation of biochemical pathways.