| 摘要 |
<p>A tunnel for forcing market-garden plants comprises >=2 cross-elements. The lateral edges of each element are folded back on themselves to form a pocket which receives an arcuate element. The ends of these elements are held on either side of the tunnel in a base plate, two adjacent elements being connected by a same base plate with 2 orifices. Pref. the tunnel is made of treated PVC sheet.</p> |
