Abstract
Interactions between organisms and species have been long known. Allelopathy is a phenomenon observed in many plants that emit specific chemicals acting on other organisms, including plants, animals and microorganisms, in either inhibitory or excitatory ways. We studied whether allelopathy is modified under altered gravity or not. If biosynthesis, emission, transport and sensing mechanism of allelopathic substances would be affected by gravity, many organisms and ecological system might show different behaviors based on the inter-organisms and -species interactions when they are exposed to microgravity. We evaluated the gravitational effects on allelopathy by applying pseudo-microgravity, generated by a 3D-clinostat, onto a plant-plant system. The allelopathic action of Mucunaon the growth of lettuce and Arabidopsis was compared between the 3D-clinostat experiment group and the ground control. Since the action of allelopathic substances, L-DOPA, was similar for the two group, gravitational effects on the transport and other process were further examined.
