Ref ID : 3033
Roger Pourriot and Pierre Clement; [Photoperiodisme et cycle heterogonique chez Notommata copeus (Rotifere Monogononte)]. Archives de Zoologie Experimentale & Generale (Arch.Zool.exp.gen.) 114:277-300, 1973
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In long-day cycles, the parthenogenetic females of Notommata copeus produce a variable number of mictic females (induction of the sexual reproduction). A. The percentage of mictic females varies with the wavelength, all other experimental conditions standing constant. An action spectrum obtained between 300 and 700 nm indicates: - an inefficiency of the radiations between 600-700 nm, - a little efficiency of the radiations between 500-600 nm, - a great efficiency of the radiations between 300-500 nm with peaks at 425-475 nm, 360-370 nm and below 310 nm. This action spectrum is compared with the absorption spectrum of photo-pigments having similar characters; carotenoids, pterins, flavins (in particular riboflavin). It differs greatly from the action spectrum obtained in phototropic reactions of other Monogononts Rotifers. The pigments involved in these two types of photoreactions, phototropism and photoperiodism, appear to be different. Comparison are made also between the spectral sensitivity in the photo-periodic reaction of N. copeus and those of other invertebrates. B. Between 400 and 620 nm, two illuminations have been experimented (315 and 21 p. Einsteins). From these results it appears that: - the wavelength action on the mictic female production shows a similar pattern at the two illuminations, - for each effective wavelength, the mictic female production varies significantly with the illumination intensity. C. The net production rate is unaffected by the wavelength or the illumination variations.