研究生：蔡景株 Ching-Chu Tsai

Effects of Endomycorrhizal Inoculation on the Root Morphology and Seedling Growth of Calocedrus macrolepis var. formosana

研究生：蔡景株 Ching-Chu Tsai

指導教授：張焜標 Kun-Piao Chang

【摘要】

本研究利用森林土、泥碳土及蛭石混合物與森林土兩種不同介質，進行臺灣肖楠幼苗接種試驗，處理方法區分殺菌與不殺菌，試驗接種包含對照組、接種混合菌種（Gigasspora gigantea 及 Acaulospora scrobiculata）、接種 Glomus intraradices 菌種、接種Glomus etunicatum 菌種與添加磷肥等五種方式。

研究目的為探討：（一）以光學顯微鏡及掃描式電子顯微鏡觀察接種苗木根系與菌根菌共生之根部形態（二）不同接種處理下幼苗菌根感染率與菌根依存度之比較，（三）不同接種處理對臺灣肖楠幼苗之苗高與根際直徑生長之影響，（四）不同接種處理對臺灣肖楠幼苗生物量之影響，（五）幼苗在不同接種處理下之植株養分含量比較。

試驗結果顯示：利用光學顯微鏡及掃描式電子顯微鏡觀察接種苗木根部形態，發現具有囊泡、胞內菌絲與叢枝體等內生菌根之特徵，證明三種菌根菌接種方法可與台灣肖楠苗木根系形成共生關係。不論混合介質或森林土，經過殺菌與否，經接種不同菌根菌種類對臺灣肖楠幼苗之生長具有促進之影響。接種Glomus intraradices 菌種優於接種混合菌種（Gigasspora gigantea 及 Acaulospora scrobiculata）與接種 Glomus etunicatum 菌種。綜合而言，台灣肖楠培育初期，接種內生菌根菌可有效促進植株之生長。

關鍵字：台灣肖楠

This study was to investigate two different soil substrates that were mixture of forest soil, peat and vermiculite and forest soil as growing medium for raising Calocedrus macrolepis var. formosana seedlings. The soil substrates used in this experiment was divided two parts, sterilized and unsterilized. The inoculation methods of each soil treatment contained control, inoculated mixed mycorrhizal fungi (Gigasspora gigantea and Acaulospora scrobiculata), inoculated Glomus intraradices , inoculated Glomus etunicatum and amended with phosphorous fertilizer.

The objectives of this study were to investigate: (1) the root morphology between mycorrhizal fungi and seedling roots under light and scanning electron microscopes, (2) comparison of infection rate and mycorrhizal dependency of seedlings in various treatments, (3) effects of growth in the height and root collar diameter of Calocedrus macrolepis var. formosana seedlings in various treatments, (4) effects of the biomass of Calocedrus macrolepis var. formosana seedlings in various treatments, (5) comparisons of nutrient content of seedlings tissue in various treatments.

The results of this study show that the vesical, intra hyphae and arbusicles are present in the mycorrhizal roots under the light and scanning electron microscope. These characteristics formed in the roots are the evidence of symbiotic relationship between three mycorrhizal fungi species and Calocedrus macrolepis var. formosana. All the soils of mixture substrate and forest soils, sterilized and not, inoculation of various mycorrhizal fungi had significant effects on the seedling’s growth of Calocedrus macrolepis var. formosana. The effects of inoculation with Glomus intraradices on seedling growth show best response among the mixed mycorrhizal fungi (Gigaspora gigantea and Acaulospora and scrobiculata ) and Glomus etunicatum. In conclusion, inoculation with endomycorrhizal fungi in cultivation of Calocedrus macrolepis var. formosana have the potential to enhance seedling growth.