Brassinosteroid regulates secondary metabolism in tomato towards enhanced tolerance to phenanthrene
2013
Ahammed, G.J., Zhejiang Univ., Hangzhou (China). Dept. of Horticulture | Zhou, Y.H., Zhejiang Univ., Hangzhou (China). Dept. of Horticulture | Xia, X.J., Zhejiang Univ., Hangzhou (China). Dept. of Horticulture | Mao, W.H., Zhejiang Univ., Hangzhou (China). Dept. of Horticulture | Shi, K., Zhejiang Univ., Hangzhou (China). Dept. of Horticulture | Yu, J.Q., Zhejiang Univ., Hangzhou (China). Dept. of Horticulture
We investigated the role of 24-epibrassinolide (EBR) in the amelioration of phenanthrene (PHE) stress in tomato. Exposure to PHE (300 microM) significantly decreased shoot and root length (19 and 16 %, respectively), fresh mass (35 and 43 %, respectively), contents of chlorophyll a (26 %), chlorophyll b (27 %) and carotenoids (18 %) in tomato plants. In addition, PHE increased the malondialdehyde (MDA) content (57 %) and activity of secondary metabolism related enzymes glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PDH), shikimate dehydrogenase (SKDH), phenylalanine ammonia-lyase (PAL) and cinnamyl alcohol dehydrogenase (CAD). The expression levels of GST1, PPO, SKDH, PAL and CAD genes were also induced by PHE. Importantly, EBR (0.1 microM) alone and in combination with PHE increased the growth, biomass and activity of those enzymes significantly over control and PHE alone, respectively. Consistent with enzymes activities transcript levels of GST1, PPO, SKDH, PAL and CAD were further increased in PHE+EBR over PHE alone. However, MDA content was remarkably decreased in PHE+EBR than PHE alone. Meanwhile, content of phenols, flavonoids and antioxidant activity were increased by PHE and PHE+EBR further increased all those parameters. These observations suggest that EBR regulates secondary metabolism in tomato which might enhance tolerance to PHE.
显示更多 [+] 显示较少 [-]