Qu L Y, Shinano T, Quoreshi A M, Tamai Y, Osaki M, Koike T
Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
Tree Physiol. 2004 Dec;24(12):1369-76. doi: 10.1093/treephys/24.12.1369.
The flow of labeled carbon in ectomycorrhizal and non-ectomycorrhizal seedlings of Japanese larch (Larix kaempferi Sarg.) and its F1 hybrid (Larix gmelinii Rupr. x L. kaempferi) was studied. Larch seedlings were grown in a greenhouse for 110 days with larch forest soil (FM) or Suillus grevillei (SM) inoculum, or in the absence of ectomycorrhizal fungi (NM). Shoots of colonized and NM seedlings were exposed to a pulse of 14CO2 for 1 h under natural light. Seedlings were harvested following 0, 6 and 24 h of exposure to 14CO2. At the final harvest, SM seedlings of Japanese larch and hybrid larch allocated 2.6 and 2.5% more 14C, respectively, to roots than NM seedlings. In contrast, FM seedlings of Japanese larch and hybrid larch allocated 6.5 and 18.0% more 14C, respectively, to the stem than NM seedlings. Of the total 14C detected in needle, stem and root fractions, FM and SM seedlings allocated a greater proportion than NM seedlings, perhaps because FM and SM seedlings had significantly (P < 0.05) higher photosynthetic rates than NM seedlings. As a result, FM and SM seedlings had greater dry masses than NM seedlings. Concentrations of nitrogen and phosphorus in FM and SM seedlings were significantly (P < 0.05) higher than in NM seedlings, as was stomatal conductance.
研究了日本落叶松（Larix kaempferi Sarg.）及其F1杂种（Larix gmelinii Rupr.×L. kaempferi）外生菌根和非外生菌根幼苗中标记碳的流动情况。落叶松幼苗在温室中用落叶松林土壤（FM）或褐环乳牛肝菌（SM）接种物培养110天，或在没有外生菌根真菌的情况下培养（NM）。在自然光下，将已定植和NM幼苗的枝条暴露于14CO2脉冲1小时。在暴露于14CO2 0、6和24小时后收获幼苗。在最终收获时，日本落叶松和杂种落叶松的SM幼苗分别比NM幼苗多分配2.6%和2.5%的14C到根部。相比之下，日本落叶松和杂种落叶松的FM幼苗分别比NM幼苗多分配6.5%和18.0%的14C到茎部。在针叶、茎和根部分检测到的总14C中，FM和SM幼苗分配的比例高于NM幼苗，这可能是因为FM和SM幼苗的光合速率显著（P<0.05）高于NM幼苗。结果，FM和SM幼苗的干质量比NM幼苗大。FM和SM幼苗中的氮和磷浓度以及气孔导度均显著（P<0.05）高于NM幼苗。
