Ameliorating Effects of Leaf Water Extract of Three Aromatic Plant Species on Ozone-Polluted Snap Bean (Phaseolus vulgaris L. ‘Jiangjunyoudou’)

Abstract

Ozone (O) is one of the major pollutants in near-surface air. In order to protect sensitive plants from O pollution, many kinds of protectants including synthetic ones, were assessed in previous studies. Although they have certain protective effects, some of them are not environment-friendly. In the present study, leaf water extracts of aromatic plants [Plectranthus hadiensis var. tomentosus (PHT), Pelargonium hortorum (PHB), Tagetes patula (TP)] were compared for mitigating the damages caused by O (150 ppb for 3 days, 8 h day) on snap bean (Phaseolus vulgaris 'Jiangjunyoudou'). Our results showed that O fumigation impaired plasma membrane, decreased chlorophyll content, increased contents of malondialdehyde and superoxide anion, inhibited photosynthesis, and caused visible injury. Leaf water extracts of PHT, PHB or TP ameliorated the negative effects of O. Among them, extract of PHT showed the greatest potential to alleviate the O-caused injury, followed by PHB and TP.

Comparative Study on Nitrogen Assimilation and Gene Regulation of different Kentucky bluegrass Cultivars in response to Nitrate supply

“…The absorbance was measured using a spectrophotometer (T6 New Century, Beijing, CN) at 665 nm and 649 nm. The total Chl content was calculated using the equation of Lichetenthaler [32].…”

“…Leaf Chla uorescence were measured at the end of treatments using a IMAGING-PAM uorometer (Zealquest, Shanghai, China). The second expanded leaf from the top on three represented plants of two cultivars was chosen for the determination of parameters under different treatments [32]. The formula of Fv/Fm was Fv/Fm=(Fm-Fo)/Fm represents the maximal quantum yield of PS .…”