作 者：Chen, J; Shen, ZJ; Lu, WZ; Liu, X; Wu, FH; Gao, GF;Liu, YL; Wu, CS;Yan, CL; Fan, HQ;Zhang, YH;Zheng, HL影响因子：3.549

刊物名称：TREE PHYSIOL

出版年份：2016

Doi:10.1093/treephys/tpw097

Avicennia marina(Forsk.) Vierh is a widespread mangrove species along the southeast coasts of China. Recently, the outbreak of herbivorous insect,Phyllocnistis citrellaStainton, a leaf miner, have impacted on the growth ofA. marina. Little is reported about the responses ofA. marinato leaf miner infection at the biochemical, physiological and molecular levels. Here, we reported the responses ofA. marinato leaf miner infection from the aspects of leaf structure, photosynthesis, and antioxidant system and miner responsive genes expression.A. marinaleaves attacked by the leaf miner exhibited significant decreases in chlorophyll, car-bon and nitrogen contents, as well as a decreased photosynthetic rate. Scanning and transmission electron microscopic observa-tions revealed that the leaf miner only invaded the upper epidermis and destroyed the epidermal cell, which lead to the exposure of salt glands. In addition, the chloroplasts of mined leaves (ML) were swollen and the thylakoids degraded. The maximal net photosynthetic rate, stomatal conductance (Gs), carboxylation efficiency (CE), dark respiration (Rd), light respiration (Rp) and quantum yields (AQE) significantly decreased in the ML, whereas the light saturation point (Lsp), light compensation point (Lcp), water loss and CO₂compensation point (Г) increased in the ML. Moreover, chlorophyll fluorescence features also had been chan-ged by leaf miner attacks. Interestingly, higher generation rate of O^{2ˉ ·}and lower antioxidant enzyme expression in the mined por-tion (MP) were found; on the contrary, higher H₂O₂level and higher antioxidant enzyme expression in the non-mined portion (NMP) were revealed, implying that the NMP may be able to sense that the leaf miner attacks had happened in the MP of theA. marinaleaf via H₂O₂signaling. Besides, the protein expression of glutathione S-transferase (GST) and the glutathione (GSH) content were increased in the ML. In addition, insect resistance-related gene expression such aschitinase 3,RAR1,toplessandPIF3had significantly increased in the ML. Taken together, our data suggest that leaf miners could significantly affect leaf structure, photosynthesis, the antioxidant system and miner responsive gene expression inA. marinaleaves.

Fig. 11.The response mechanism of A. marina to leaf miner attacks. NMP, non-mined portion of mined leaves; MP, mined portion of mined leaves.