TY - JOUR AU - Li, Yue AU - Ma, Junqiang AU - Wang, Yu AU - Xu, Sunan AU - Jiang, Lei AU - Zhang, Lihong AU - Hou, Wei PY - 2023/03/31 Y2 - 2024/03/28 TI - Effects of exogenous NO on the growth and photosynthetic fluorescence characteristics of ryegrass seedlings under B[a]P stress JF - Acta Botanica Croatica JA - Acta Bot. Croat. VL - 82 IS - 1 SE - Articles DO - 10.37427/botcro-2023-004 UR - https://www.abc.botanic.hr/index.php/abc/article/view/3561 SP - AB - <p>Benzoapyrene (B[a]P) pollution poses a threat to the environment and the food chain and consequently to human health. However, the alleviation of the harmful effects of B[a]P pollution in perennial ryegrass (<em>Lolium perenne</em> L.) by the application of exogenous nitric oxide (NO) has been ignored. Thus, in this paper the effects of exogenous sodium nitroprusside (SNP, a NO donor) on the growth, photosynthetic fluorescence characteristics, and antioxidant enzyme activity of ryegrass exposed to B[a]P stress are investigated. B[a]P stress induced the reduction of the aboveground and belowground dry weights, chlorophyll (<em>a</em>, <em>b</em>), the total chlorophyll contents, the carotenoid content, the net photosynthetic rate (Pn), the intercellular carbon dioxide concentration (Ci), the water use efficiency (WUE), the photosystem II (PSII) potential activity (F<sub>v</sub>/F<sub>0</sub>), the maximum quantum yield of PSII photochemistry (F<sub>v</sub>/F<sub>m</sub>), the steady-state fluorescence yield (F<sub>s</sub>), and the non-photochemical quenching (qN), while enhancement was recorded in response to the foliar spray of SNP at 200 and 300 μmol L<sup>-1</sup> under B[a]P stress. Gray correlation and principal component analyses show that 200 μmol L<sup>-1</sup> of SNP more drastically alleviated the damage caused by B[a]P stress than 300 μmol L <sup>-1</sup> of SNP. The exogenous NO-mediated alleviation of B[a]P toxicity in ryegrass was associated with preserved photosynthetic characteristics and activation of antioxidant enzymes.</p> ER -