关键词: 连翘, 茉莉酸甲酯, 叶片, 光合作用, 次生代谢

Abstract: In order to improve the quality and yield of F.suspensa,the F.suspensa leaves were sprayed with 1,0.1, and 0.01 mmol/L MeJA.Taking the spraying water treatment as a control, the effects of spraying different concentrations of MeJA on the photosynthetic characteristics,SPAD value,PAL activity and the content of secondary metabolites such as total flavonoids, forsythin, and forsythoside A of F.suspensa leaves were studied.The results showed that, different concentrations of MeJA and different treatment time had different effects on the Pn,Tr,Gs and Ci of F.suspensa leaves.For a certain period, MeJA showed inhibition of high concentration and promotion of low concentration on Gs and Tr.The SPAD value showed a trend of first declining and then rising with the extension of the time after spraying.At 2,6,24,48 and 72 hours 0.01 mmol/L MeJA treatment increased the accumulation of total flavonoids by 18.70%,34.13%,30.16%,40.57%,11.02% compared with the control, respectively.The 0.01 mmol/L MeJA treatment increased forsythin to a certain extent,but it showed an inhibitory effect on the accumulation of forsythoside A.At 2 h and 6 h after spraying MeJA,the PAL activity of each treatment increased compared with the control.At 48 h after spraying, the PAL activity of 1,0.1,0.01 mmol/L MeJA spraying treatments decreased by 15.88%, 12.38% and 12.56% compared with the control, respectively. In summary,the accumulation of secondary metabolites of F.suspensa leaves at 48 h after spraying 0.01 mmol/L MeJA can be significantly increased.

Key words: Forsythia suspensa, MeJA, Leaf, Photosynthesis, Secondary metabolism