The activities of NAD- and NADP-dependent glutamate dehydrogenases (GDH) in vegetative mycelia of Lentinus edodes increased in the earlier growth stages, i.e., 5 to 10 days after inoculation, as well as the time of fruit-body formation when strain No. 68 was cultivated in peptone-glucose-vanillin (PGV), peptone-glucose-glucuronic acid (PG-GIcU) and peptone-glucose-vanillin-glucuronic acid (PGVGIcU) liquid media. The GDH activities also increased in young fruit-bodies. No significant increase was observed in mycelial GDH activities and fruit-body yield when the strain was grown in PG liquid medium. The addition of 1.0 mM diethyldithiocarbamate (DETC) to the culture medium on the 7th day of incubation, when GDH activity was at a peak, inhibited the activity of NAD-GDH as well as fruit-body formation. However, no inhibition was observed when DETC was added on the 21st day of incubation. When vanillin (50 µg/ml) and glucuronic acid (2 mg/ml) were added on the 10th and 15th day of incubation in PG medium, the activity of NAD-GDH and mycelial dry weight increased with production of fruit-bodies, but the addition of DETC at the same time inhibited the activity of NAD-GDH, mycelial growth and fruit-body formation. No effect was observed when vanillin and glucuronic acid were added on the 20th day of incubation. Addition of ferulic acid to the glutamate medium (Glu) enhanced mycelial growth and GDH activities on Glu medium. These results indicated that the reproductive process of L. edodes starts by the 20th day of incubation and the stimulated GDH activities in the eary growth stages in the presence of phenolic compounds and uronic acids may be responsible for the induction of fruit-body formation.

　The nutritional requirements for the vegetative growth of Lyophyllum fumosum (Pers.: Fr.) P. D. Orton were investigated by use of a synthetic liquid medium. A wide range of carbohydrates served as carbon source in the medium which supported growth of L. fumosum. Glucose, mannose, fructose, sucrose, dextrin, glycogen, pectin and soluble starch were especially good carbon sources for mycelial growth. Yeast extract, soyton, peptone, meat extract, casamino acid and the amino acids mixture of the basal medium were acceptable nitrogen sources for the growth, while ammonium and nitrate salts were poor nitrogen sources. The amino acids mixture in the culture medium could be replaced by l-valine and l-citrulline. The vegetative mycelium did not grow in the absence of KH₂PO₄ and MgSO₄, and the yield of mycelium was decreased by the omission of ZnSO₄, FeSO₄, CuSO₄, MnSO₄, thiamine and nicotinamide. The vegetative mycelium yield was increased in the basal medium containing 0.1-1 mg/l of indole-3-acetic acid (IAA), kinetine, gibberellic acid, 1-naphthyl acetic acid (NAA) and 2, 4-dichlorophenoxy acetic acid (2,4-D), but it was decreased in the basal medium containing 10 mg/l of IAA and NAA.

　The number of urediniospores in the telium of Zaghouania phillyreae increased from early winter (January) to early spring (March). Finally the telium was completely filled with urediniospores and had apparently become a uredinium. A spore-like body showing some of the characteristics of both basidiospores and urediniospores was occasionally observed at the bottom of a teliospore.

　In room experiments, the ratio of numbers of urediniospores to basidiospores was not directly related to air temperature. However, the rate of increase of urediniospores was slow at low temperature (5-10°C) when test leaves were collected while teliospores and basidiospores were formed abundantly in the field.

　The identification of water moulds of the family Saprolegniaceae has been based on their asexual and sexual characteristics. In this study, we attempted to classify the three genera Saprolegnia, Achlya and Aphanomyces in the Saprolegniaceae from some of their biological characteristics. The optimal temperatures for growth were 20-25°C, 30-35°C and 25-30°C for Saprolegnia, Achlya and Aphanomyces, respectively. The three genera also differed in their sensitivities to malachite green, NaCl, K₂HPO₄, sorbose and Polyphenon-100^R. The strains tested were decreasingly sensitive of NaCl and K₂HPO₄ in the order of Aphanomyces, Achlya and Saprolegnia, and to malachite green, Polyphenon-100^R and sorbose in the order of Apanomyces, Saprolegnia and Achlya. From the sensitivity tests of Aphanomyces to Polyphenon-100^R and sorbose, the pathogenic strain A. piscicida could be distinguished from the saprophytic strains. The three genera in the Saprolegniacease and some species in these genera could thus be classified on the basis of certain biological characteristics. Biological tests might thus be applicable for the classification of fungi belonging to certain genera of the Saprolegniaceae.

　Gravity is one of the factors guiding growth in fungi. We summarize what is known about gravitropism in Phycomyces sporangiophore―one of the most developed model systems considering "stimulus perception―stimulus transduction―response" system in fungi.

　Compared with response to light, gravitropism in Phycomyces appears to be less effective in respect to the latency period and the speed of response. Maybe this is the reason why studies on gravitropism have been less intensive, resulting in obscure and sometimes contradictory information on receptors and involved mechanisms.

　There are several parameters influencing the gravitropic response: developmental stage and diameter of the sporangiophore, absolute growth rate, ratio of differential growth. The interplay between gravity and light is expressed in two ways: influence of light on gravisensitivity and tropic equilibrium when both stimuli are present simultaneously.

　Attempts to dissect the mechanism of gravitropic response and to model its kinetics involve experiments in a microgravity environment as well as application of centrifugal force. The gravireceptor is suspected to be localized in the growth zone but has not yet been identified. Further progress in the gravitropic studies could be achieved using mutants with impaired or enhanced perception of gravitational stimuli.