In addition to lipids the spores of Dicranum scoparium L. Hedw. contain granular storage material, which is stained by mercuric bromphenol blue and digested by pepsin treatment. When these proteins are degraded during germination, it is evident that they are vacuole-bound and similar to the protein bodies of higher plants. There are few starch grains in the chloroplasts of ungerminated spores. The amount of starch increases at the beginning of germination and decreases during later stages. These changes are accompanied by changes in the chlorophyll and protein content of the sporelings. Protein storage material is not common in the spores of lower Archegoniatae but has been observed in some Pteridophyta (Gantt & Arnott, 1965; Gullvag, 1968a). The main reserve material of the moss spores so far investigated is fat (e.g., Afzelius, 1957; Kofler, 1959; Valanne, 1966; Karunen, 1972). On the other hand, storage material is not always necessary for germination of moss spores, since in many species well-developed functional chloroplasts are present in ungerminated spores (e.g. Gullvag, 1968b; Nurit, 1971) and can begin photosynthesis immediately after swelling of the spores (Paolillo & Jagels, 1969). The main purpose of this study was to demonstrate the nature of the granular, proteinaceous storage material seen in electron micrographs of the spores of Dicranum scoparium and to follow the dissolution of this material and the development of chloroplasts during germination. MATERIALS AND METHODS Spores of Dicranum scoparium (L.) Hedw. were collected in Piikki6, in southwest Finland, in the autumns of 1971-1973. Germination of this species is more rapid and synchronous on agar than in liquid cultures (Fig. 1). Later development of the sporelings is also more normal on agar, as is evident from the lower chlorophyll content of sporelings in liquid medium and the lower ratio of chlorophyll a to b (1.50 after two weeks in liquid cultures, as opposed to 2.17 on agar cultures). Intact capsules were sterilized (Valanne, 1966) and dried overnight on silica gel. Dry spores were sown on cellophane membrane on 1% Bacto-agar in an inorganic nutrient solution (MS, Waris, 1953). The petri dishes were placed in a growth chamber at 20'C and in continuous light emitted by Philips TLF 40W/55 fluorescent tubes with an intensity of 10,000 lux. 1 We express our sincere thanks to Mrs. Ulla-Maija Suoranta for skillful technical assistance. 2 Department of Botany, University of Helsinki, SF-00170 Helsinki 17, Finland. SDepartment of Botany, Institute of Biology, University of Turku, SF-20500 Turku 50, Finland. This content downloaded from 207.46.13.129 on Mon, 18 Apr 2016 08:46:33 UTC All use subject to http://about.jstor.org/terms 1976] VALANNE, TOIVONEN & SAARINEN: PROTEIN IN MOSS SPORES 189