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While studying the reproductive biology of Saffron (Crocus sativus L.) grown in the Botanical Gardens of the University of L'Aquila (Italy) (Grilli Caiola et al. 1982) it was found that many cells of the ovary, style and stigma contained particles similar to those found by Russo et al. (1979) in the leaf and root cells of the same Saffron species and identified as latent Bean yellow mosaic virus. Because Saffron cultivation in the Region Abruzzo (Italy) is economically important (Tammaro and De Francesco 1978) it was thought useful to draw attention to the possibility that besides other diseases also viruses could be the cause of reduced production of that crop. [ABSTRACT FROM AUTHOR]

Water fern (Azolla filiculoides Lam.) has been assessed for nitrogen and phosphorus removal in outdoor experiments comparing sewage water (S) from an experimental aquaculture plant, well water (W) and mineral growth medium Hoagland (H). The experiments were undertaken during the spring and the summer. The yield of fern biomass and nitrogenase activity was higher in H than in W and S waters. The enzyme activity had a decreasing trend with significant differences (p < 0.05) in the three waters. Peroxidase (POD) activity in April decreased with significative differences in W and S waters (p < 0.05). The electrical conductivity and the concentrations of NO3- in the three waters decreased significantly (p < 0.05). The highest removal of nitrate from the media was obtained in July. In S water, NO2- concentration decreased, while it increased in W water. PO(4)3- concentration was very low in W and S waters and decreased in H medium. The results obtained confirm the ability of the fern to grow in sewage water.

Superoxide dismutase was investigated in the symbiont Anabaena azollae Strasb. living in Azolla filiculoides Lam. In vegetative cells, three isoenzymatic forms of superoxide dismutase, containing manganese, iron, and the hybrid iron-manganese, respectively, were present. Hybrid superoxide dismutase, detected for the first time in cyanobacteria, was 7% of the total superoxide dismutase present in vegetative cells. All three superoxide dismutase forms increased in the Anabaena vegetative cells obtained from irradiated plants grown in winter. In heterocysts, only an iron superoxide dismutase was present, which amounted to 25% of total vegetative cell superoxide dismutase activity. Hybrid superoxide dismutase appeared in heterocysts after irradiation. In vegetative cells of Anabaena from plants grown in summer, the basal level of total superoxide dismutase increased by 60% as compared with winter, and was unaffected by irradiation. The levels of superoxide dismutase in heterocysts from control and exposed plants grown in summer were comparable to those observed in heterocysts obtained from the plants grown during winter. No direct correlation was found between nitrogenase activity and superoxide dismutase in heterocysts. The presence of cyanophycin granules, either within the heterocyst pore channel or close to the transversal septum of vegetative cells, suggested a mechanism to stop communications between vegetative cells and heterocysts.