ABSTRACT: We investigated the effect of ectomycorrhizal colonization, charcoal and CO2 levels on the germination of seeds of Larix kaempferi and Pinus densiflora, and also their subsequent physiological activity and growth. The seeds were sown in brown forest soil or brown forest soil
mixed with charcoal, at ambient CO2 (360μmolmol−1) or elevated CO2 (720μmolmol−1), with or without ectomycorrhiza. The proportions of both conifer seeds that germinated in forest soil mixed with charcoal
were significantly greater than for seeds sown in forest soil grown at each CO2 level (P<0.05; t-test). However, the ectomycorrhizal colonization rate of each species grown in brown forest soil mixed with charcoal was
significantly lower than in forest soil at each CO2 treatment [CO2] (P<0.01; t-test). The phosphorus concentrations in needles of each seedling colonized with ectomycorrhiza and grown in forest soil were
greater than in nonectomycorrhizal seedlings at each CO2 level, especially for L. kaempferi seedlings (P<0.05; t-test), but the concentrations in seedlings grown in brown forest soil mixed with charcoal were not increased at any CO2 level. Moreover, the maximum net photosynthetic rate of each seedling for light and CO2 saturation (P
max) increased when the seedlings were grown with ectomycorrhiza at 720μmolmol−1 [CO2]. Ectomycorrhizal colonization led to an increase in the stem diameter of each species grown in each soil treatment at each
CO2 level. However, charcoal slowed the initial growth of both species of seedling, constraining ectomycorrhizal development.
These results indicate that charcoal strongly assists seed germination and physiological activity.
Landscape and Ecological Engineering 04/2012; 5(2):107-113. · 0.64 Impact Factor