Effects of exogenous NO on the growth and photosynthetic fluorescence characteristics of ryegrass seedlings under B[a]P stress

Benzoapyrene (B[a]P) pollution poses a threat to the environment and food chain consequently human health. However, alleviation of harmful effects B[a]P in perennial ryegrass ( Lolium perenne L.) by application exogenous nitric oxide (NO) has been ignored. Thus, this paper sodium nitroprusside (SNP, NO donor) on growth, photosynthetic fluorescence characteristics, antioxidant enzyme activity exposed stress are investigated. induced reduction aboveground belowground dry weights, chlorophyll (a, b), total contents, carotenoid content, net rate (Pn), intercellular carbon dioxide concentration (Ci), water use efficiency (WUE), photosystem II (PSII) potential (Fv/F0), maximum quantum yield PSII photochemistry (Fv/Fm), steady-state (Fs), non-photochemical quenching (qN), while enhancement was recorded response foliar spray SNP at 200 300 μmol·L-1 under stress. Gray correlation principal component analyses show that μmol·L 1 more drastically alleviated damage caused than SNP. The NO-mediated toxicity associated with preserved characteristics activation enzymes.