瓶内接种菌根真菌对毛棉杜鹃生长与抗性酶的影响.

[Objective] The study of Rhododendron moulmainense inoculation with mycorrhizal fungi was conducted to selecl the better strains, and to provide the reference for improving breeding efficiency, also to reveal the mechanism of improving plant resistance by mycorrhizal fungi. [ Meth oil]7 kinds ericoid mycorrhizal fungis, separated from wild Rhododendron moulmainense, were used to inoculate Rhododendron moulmainense tissue culture seedling. Growth situation was observed regularly, and height growth rate, biomass growth rate, mycorrhizal infection rate, disease index, PAL and LOX activity were determined. [Result] (i) Plants of control group were wizened after 2 weeks, but plants of mycorrhizal inoculation treatment were viable, (ii) Height growth rates and biomass growth rates of No. 7 treatment were the highest, 71.81 % and 83.62 % respectively, No. 17 and No. 14 treatment fllowed. Mycorrhizal infection rales of No. 16 treatment were the highest, No.1 treatment were the lowest. Disease indexes of No. 7 were the lowest, No. 5 and No. 3 were the highest. PAL and LOX activity of each mycorrhizal inoculation treatment all higher than control group. PAL and LOX activity of No. 16 treatment were the highest, 4. 82 and 0. 88 U/mg respectively, PAL activity of No. 1, No. 5, No. 17 were the lowest, 1.90 -2. 20 U/mg, LOX activity of No.1, No. 3 were the lowest, 0. 29 -0. 38 U/mg. The correlation analysis showed that, colonization intensity were positively correlated with PAL and LOX activity significantly, but disease index were negatively correlated with PAL and LOX activity. [Conclusion] Each of the 7 kinds ericoid mycorrhizal fungi could form mycorrhizal symbionts with Rhododendron moulmainense, but different fungis had different impact on growth of host plants, the result showed that, No.7 (Bionectria ochroleuca) was the optimal fungi, No. 14(Aspergillus sydowii)and No. 17(Paecilomyces javanicus) were the second choices. Higher mycorrhizal infection rate helped to improve PAL and LOX activity. It may have an impact on resistant and growth of plants, but resistant and growth of plants were more impacted by species of fungi. [ABSTRACT FROM AUTHOR]