Bryophytes play important ecological roles in terrestrial ecosystems,but their growth is often influenced by environmental factors and chemical interactions with surrounding vegetation.Fallen leaves are an important s...Bryophytes play important ecological roles in terrestrial ecosystems,but their growth is often influenced by environmental factors and chemical interactions with surrounding vegetation.Fallen leaves are an important source of allelopathic substances,yet little is known about their impact onmosses.This study investigates the allelopathic effects of fallen leaves from Cinnamomum camphora,Pinus massoniana,and Bambusa emeiensis on the bryophyte Thuidium kanedae in Guiyang.The litter aqueous extract(0.0125 g/mL(T1),0.025 g/mL(T2),0.05 g/mL(T3),0.1 g/mL(T4)and distilled water control(CK))was used to regularly water and culture T.kanedae.During the 120-day test period,the physiological indexes such as new shoot length,branch length,branch number,coverage area,biomass,chlorophyll(Chl t),soluble protein(SP),soluble sugar(SS),malondialdehyde(MDA)content,peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD)activities were measured regularly,and the Allelopathic effect response index(RI),the Synthetic allelopathic effect index(SE)and the Average synthetic allelopathic effect index(ASE)were calculated.The results indicated that the Allelopathic effect response index(RI)and the Synthetic allelopathic effect index(SE)of the three plant fallen leaf extracts on new main stem length,branch length,coverage area,and biomass of T.kanedae exhibit a“promotion at low concentrations and inhibition at high concentrations”trend.Specifically,at a concentration of T1,a promotive effect was observed,while concentrations greater than T1 generally began to show inhibitory effects,with the strongest inhibition occurring at T4.Correlation analysis showed that growth indicators were significantly negatively correlated with extract concentration,MDA content and SOD activity,while showing significant positive correlations with Chl t content,SS content and CAT activity.The ASE of the three plant species exhibited significant variation,ranging frominhibition to promotion,with the sequence being:C.camphora(−0.170)>B.emeiensis(−0.032)>P.massoniana(0.001).This indicates that the strength of allelopathic effects is influenced by the species of the donor plants.Overall,the allelopathic effects on T.kanedae are both concentration-dependent and species-specific.展开更多
A new bidihydroflavonoid, thuidinin 1, together with 5 known compounds including one known biflavonoid 3＇,3＂＇-binaringenin （2） and four other known natural products pentadecane （3）, methyl β-orcinolarboxylate ...A new bidihydroflavonoid, thuidinin 1, together with 5 known compounds including one known biflavonoid 3＇,3＂＇-binaringenin （2） and four other known natural products pentadecane （3）, methyl β-orcinolarboxylate （4）, β-sitosterol （5） and daucostenol （6）, were isolated from leaves of Thuidium kanedae Sak. Their structures were established on the basis of 1D and 2D spectroscopic analysis. The absolute stereochemistry of compounds 1 and 2 was determined by CD spectra.展开更多
基金funded by the National Natural Science Foundation of China,“Landscape Adaptation Evaluation of Bryophytes in Karst Areas and its Landscape Theory”(31960328),awarded to Xiurong Wang.
文摘Bryophytes play important ecological roles in terrestrial ecosystems,but their growth is often influenced by environmental factors and chemical interactions with surrounding vegetation.Fallen leaves are an important source of allelopathic substances,yet little is known about their impact onmosses.This study investigates the allelopathic effects of fallen leaves from Cinnamomum camphora,Pinus massoniana,and Bambusa emeiensis on the bryophyte Thuidium kanedae in Guiyang.The litter aqueous extract(0.0125 g/mL(T1),0.025 g/mL(T2),0.05 g/mL(T3),0.1 g/mL(T4)and distilled water control(CK))was used to regularly water and culture T.kanedae.During the 120-day test period,the physiological indexes such as new shoot length,branch length,branch number,coverage area,biomass,chlorophyll(Chl t),soluble protein(SP),soluble sugar(SS),malondialdehyde(MDA)content,peroxidase(POD),catalase(CAT)and superoxide dismutase(SOD)activities were measured regularly,and the Allelopathic effect response index(RI),the Synthetic allelopathic effect index(SE)and the Average synthetic allelopathic effect index(ASE)were calculated.The results indicated that the Allelopathic effect response index(RI)and the Synthetic allelopathic effect index(SE)of the three plant fallen leaf extracts on new main stem length,branch length,coverage area,and biomass of T.kanedae exhibit a“promotion at low concentrations and inhibition at high concentrations”trend.Specifically,at a concentration of T1,a promotive effect was observed,while concentrations greater than T1 generally began to show inhibitory effects,with the strongest inhibition occurring at T4.Correlation analysis showed that growth indicators were significantly negatively correlated with extract concentration,MDA content and SOD activity,while showing significant positive correlations with Chl t content,SS content and CAT activity.The ASE of the three plant species exhibited significant variation,ranging frominhibition to promotion,with the sequence being:C.camphora(−0.170)>B.emeiensis(−0.032)>P.massoniana(0.001).This indicates that the strength of allelopathic effects is influenced by the species of the donor plants.Overall,the allelopathic effects on T.kanedae are both concentration-dependent and species-specific.
文摘A new bidihydroflavonoid, thuidinin 1, together with 5 known compounds including one known biflavonoid 3＇,3＂＇-binaringenin （2） and four other known natural products pentadecane （3）, methyl β-orcinolarboxylate （4）, β-sitosterol （5） and daucostenol （6）, were isolated from leaves of Thuidium kanedae Sak. Their structures were established on the basis of 1D and 2D spectroscopic analysis. The absolute stereochemistry of compounds 1 and 2 was determined by CD spectra.
