title: Effects of weightlessness, space orientation and light on geotropism and the formation of fruit bodies in higher fungi.
abstract: The effect of flight factors on the growth and development of the fruit bodies of the higher fungus Polyporus brumalis is investigated under the conditions of an experiment on the earth satellite Cosmos 690. Fungi were grown on the earth under conditions of simulated flight and transit; fungi were also grown in the laboratory at a temperature similar to that in flight, at various orientations and under various illuminations. Polyporus brumalis grows well on wort; it forms fruit bodies on long pedicles (up to 25 cm) and possesses a strongly marked negative geotropism. Investigations have shown that the formation of hymenium and pileus is induced by definite time exposures to light. In darkness the formation of fruit bodies takes place, but without formation of hymenium and pileus, and the rate of growth is greater than in light. The strong negative geotropism remains in fruit bodies when developed in darkness and with test-tubes in a vertical position. When the test-tube orientation is changed the pedicles change direction in darkness as well as in light. In maintaining their negative geotropism the fruit bodies bend with changes of space orientation. In the absence of gravity a disorientation of fruit bodies takes place, and the pedicles are strongly twisted into a spiral or into a ball. A flattened type of fruit body can also occur. Such a picture of growth and formation was not observed in control samples. Thus, there is a strong dependence of the formation of the fruit body of Polyporus brumalis on space orientation, gravity and light.
authors.affiliation: Laboratory of Space Biology, Laboratory of Antibiotics, Lomonosov State University, Moscow, USSR.
authors.forename: G G
authors.initials: GG
authors.lastname: Zharikova
authors.forename: A B
authors.initials: AB
authors.lastname: Rubin
authors.forename: A V
authors.initials: AV
authors.lastname: Nemchinov
mesh_terms: D018522:Gravitropism; D008027:Light; D018514:Plant Structures / Q000254:growth & development / Q000528:radiation effects; D011124:Polyporaceae / Q000254:growth & development* / Q000528:radiation effects; D013026:Space Flight; D014893:Weightlessness; D018474:Weightlessness Simulation