Functional characterization of selective genes responsible for growth promotion in Chinese cabbage (Brassica campestris subsp. Chinensis L.) colonized by Piriformospora indica

• Main Authors: Chih-Wei Kao, 高志維
• Other Authors: 葉開溫
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/86515103067883885240

碩士 === 國立臺灣大學 === 植物科學研究所 === 102 === Piriformospora indica (P. indica) is a new root endophytic fungus belonging to the Hymenomycetes of the Basidiomycota. P. indica interacts with the roots of various mono- and dicotyledonous plants, showing the positive effect on biomass production. In addition to this growth promoting effect, P. indica also has the potential to induce resistance to fungal disease and to increase the antioxidative activities of plants. After the colonization of P. indica, plant becomes more tolerance to salt and drought. In this study, we used Chinese cabbage (Brassica campestris subsp. chinensis L.) for colonization with P. indica. After colonization for 7 days, six genes expression level of glutathione-S-transferase parC (BcGSTU), aux resistant 1 (BcAUX1) , efflux carrier, (BcPIN3), V-type proton ATPase (BcV-ATPase), expansin A17 (BcEXPA17),and root hair defective 4 (BcRHD4) were up-regulated and we have constructed above genes in pCAMBIA1300-35S-nos vector and tend to investigate gene function of the overexpressing cabbages. In glutathione assay, we found out the concentration of glutathione increased especially in leaves when Chinese cabbage colonized with P. indica. According to this result, we studied the tolerance Chinese cabbage colonized with P. indica under different stress. The results show that Chinese cabbage colonized with P. indica reduced the concentration of hydrogen peroxidase under NaCl stress indicated P. indica could enhance the salt tolerance of Chinese cabbage. We overexpressed these six gene in Arabidopsis and found out these gene could up-regulate the glutathione content and promote the growth of laterial roots, root length, and biomass. 35S::BcRHD4 could promote root hiars and 35S::BcGSTU could against the salt stress and drought sress. We figured out that glutathione play a role in plant growth and tolerance by P. indica colonized with Chinese cabbage.