Light quality and sporulation in Myxomycetes with special reference to a red, far-red reversible reaction.

Abstract

The effects of red, blue, green and white light on the sporulation of three slime molds are summarized as follows: 1. Physarum gyrosum (white) andDidymium iridis (brown) fruit in blue and red light but not green. 2. Physarum polycephalum fruits in blue and green light but not red. 3. All three species above fruit in both blue and white light. 4. Blue light supplies the least total energy and red light provides the most total energy prior to fruiting in these three species. 5. The plasmodium ofPhysarum gyrosum changes from white to yellow in white and blue light prior to fruiting, and from white to brown in red light prior to fruiting. In green light, which does not induce fruiting, there was no plasmodial color change. 6. Didymium iridis andPhysarum polycephalum fruit in near-red but not far-red light and far-red prevents the fruiting response promoted by near-red in both species. 7. InDidymium iridis, near-red reverses the inhibition to fruiting imposed by far-red light.