PHOTOCONTROL OF SPORE GERMINATION IN POLYPODIUM VULGARE L.

Summary Spore germination in the. fern Polypodium vulgare is induced by light at all wavelengths from blue to far‐red, although red light is most effective. The action spectrum for germination together with observations on the photoreversible effects of red and far‐red light provide evidence for the involvement of phytochrome, but the effects of blue light, particularly its interactions with red light, are incompatible with an interpretation in terms of phytochrome alone. It is suggested that two pigments are involved, phytochrome and a blue light absorbing pigment, but that not all spores contain effective levels of both pigments.