The time of urea treatment and its effects on the succession of ammonia fungi in two warm temperate forests in Japan

Abstract

We studied the effects of the timing of urea treatment on the succession of ammonia fungi. In two evergreen Castanopsis cuspidata forests and in one deciduous Quercus serrata forest, we applied 343 g urea to 25 and 15 plots of 0.5 m 2 , respectively, at three different times of the year. Ten of the early-phase (EP) species, considered to be saprotrophic, and 6 of the late-phase (LP) ones, considered ectomycorrhizal, fruited. In both phases, the commencement, peak, and cessation of fruiting took place simultaneously among all the plots treated at the same time. The fruiting occurred in summer and autumn. Quantity and size of the fruit bodies was larger in the LP than in the EP species. Fruiting of EP species was affected by the treatment time and that of LP species by interaction of the treatment time and vegetation type. EP was short and occurred as one period, whereas LP was long and occurred as two or more fruiting seasons. We found that species composition, dominant species, and degree of its dominance in fruiting of the ammonia fungi are predictable for different treatment times of the year and different vegetation types.

Experimental and physiological ecology of ammonia fungi: studies using natural substrates and artificial media

“…As previously described, the mycobiota of ammonia fungi has been examined by application of substances such as aqueous ammonia, ammonium salts yielding alkalinity in soil, and urea in different vegetation types (Sagara 1975;Suzuki 1992Suzuki , 2000aFukiharu and Hongo 1995;Yamanaka 1995a-c;Fukiharu and Horigome 1996;Fukiharu et al 1997;Sato and Suzuki 1997;Imamura 2001;Suzuki et al 2002a;Nagao et al 2003;He and Suzuki 2004;Imamura and Yumoto 2004) as well as by chemical treatment of substrates in the laboratory level (Sagara 1975(Sagara , 1976a(Sagara ,c, 1992Fukiharu and Horigome 1996;Suzuki et al 2002a;Suzuki 2004). The litter bag method is appropriate for field analysis of the litter decomposition capabilities of microorganisms (Robertson and Paul 2000;Wall and Reichman 2000), although inevitably the method involves disturbance when the bags are embedded in soil and restrict the movement of soil animals.…”

“…Ammonia fungi can be divided into two groups based on their succession in the field. One group comprises species that appear in the early phase in the succession (EP fungi; anamorphic fungi → Ascomycota → smaller Basidiomycota) while those of the second group appear in the late phase of the succession (LP fungi; larger basidiomycota) (Sagara 1995;Yamanaka 1999Yamanaka , 2003Imamura and Yumoto 2004). All the EP fungi are saprobic (=saprotrophic) (Yamanaka 1999(Yamanaka , 2003, mostly litter-decomposing fungi as speculated based on their observed litter-decomposing abilities (Enokibara et al 1993;Yamanaka 1995a;Soponsathien 1998a,b;cf.…”

Dynamics of fruit-body production and mycorrhiza formation of ectomycorrhizal ammonia fungi in warm temperate forests in Japan

“…These studies proved that a limited number of fungal species (10-20 species) frequently develop a very large quantity of fruit bodies (maximum, 50 g/m 2 in dry weight; Sagara 1975Sagara , 1976aFukiharu 1991;Imamura and Yumoto 2004a) on small plots (experimental unit, 0.5 m 2 ) after the treatment. Especially, the dominant fungal species develop fruit bodies on almost all the treated plots (Fukiharu 1991;Imamura and Yumoto 2004a).…”

“…Sequential fruit-body production of the ammonia fungi in the fi eld has been induced by applying a large amount of urea to forest soil (about 350 g N/m 2 ; Sagara 1975Sagara , 1976aFukiharu 1991;Fukiharu and Hongo 1995;Yamanaka 1995a-c;Fukiharu et al 1997;Imamura 2001;Suzuki et al 2002;Imamura and Yumoto 2004a). These studies proved that a limited number of fungal species (10-20 species) frequently develop a very large quantity of fruit bodies (maximum, 50 g/m 2 in dry weight; Sagara 1975Sagara , 1976aFukiharu 1991;Imamura and Yumoto 2004a) on small plots (experimental unit, 0.5 m 2 ) after the treatment.…”

Effect of biotic and abiotic factors on conidial germination of a saprobic ammonia fungus Amblyosporium botrytis

“…Based on the chemo-ecological characteristics described above, A. botrytis is categorized as one of the fungal species in ammonia fungi (Sagara 1975). A. botrytis occurs at the early phase (EP) of fungal succession of ammonia fungi (Yamanaka 2003; Imamura and Yumoto 2004). The occurrence of A. botrytis would happen through the effects of multiple biotic and abiotic factors.…”