臺灣菟絲子的吸器與寄主

Host Plants and the Haustorium of Cuscuta Japonica Choisy var. Formosa (Hay.) Yunker (Convolvulaceae)

菟絲子類屬寄生性植物，為害許多經濟作物。臺灣產有二種；一為菟絲子（Cuscuta australis R. Brown）另一為臺灣菟絲子（C. japonica Choisy var. formosana (Hay.) Yunker）。本次報告針對臺灣菟絲子之寄主及吸器進行研究。野外調查可知至少有36種寄主；包括果樹、野生木本植物和一年生或多年生草木植物。又如纏繞寄主之方向性全為逆時針方向。有關吸器之探討、初步瞭解；有二種類型；一為細胞間型，一為細胞內型；隨寄主而定。吸器先端之入侵也受寄主內部構造影響。具前吸器及刷狀構造並有類似單寧細胞在先端等，是臺灣菟絲子常見特徵。

Cuscuta (dodder) are parasitic plants that attack many commercial crops and orchards. There are two species in Taiwan; i.e., C. australis R. Brown and C. Japonica Choisy var. formosana (Hay.) Yunker. In this report we present the work on the host plants and the haustorium of the latter species. Field studies indicate that at least 36 host plants are attacked by this dodder including fruit trees, naturally occurring woody species, many herbaceous annual and perennial plants. The spiral growth of this dodder uniformly shows the directions to right, counterclockwise. Two types of hyphae including intercellular and intracellular type are found which variable with host plants. The penetration of the tip of the haustorium is also under the influence of internal structure of the host. The presence of prehaustorium, brush like structure and granulated cells in the tip of haustorium are a general feature of this dodder.