PROBLEM TO BE SOLVED: To solve the problems wherein the larger amount of lighting and heating expenses for kerosene, heavy oil or the like is required as the volume of a plastic greenhouse becomes larger, because the temperatures of the crops produced by a bed installed in a high position in the plastic greenhouse cannot be kept by using a tunnel or the like used for the purpose of temperature keeping at soil culture to require the heating of the whole greenhouse as the temperature-keeping practice, and the tunnel also usable as insect-controlling measures for preventing the crops from being damaged by the pests is limited to the soil culture. SOLUTION: The assistant material enabling the tunnel targeting the temperature keeping and insect proofing to be installed as same as the case of the soil culture in the bed installed in the high position in the plastic greenhouse is constituted of prop parts and pipe cap parts by utilizing a pipe part of the bed installed in the high position assembled by metallic pipes or the like. COPYRIGHT: (C)2008,JPO&INPIT
