Effects of different nitrogen sources on interactions between ammonia fungi and non-ammonia fungi.

Four early-phase (EP) and one late-phase (LP) ammonia fungi were co-cultured with three non-ammonia fungi on urea, ammonium, nitrite and nitrate agar media at different pH values (5.5, 7.0 and 9.0). The early stage EP species Amblyosporium botrytis and Ascobolus denudatus showed deadlock competition with the non-ammonia fungi Aspergillus niger and Penicillium citrinum on urea agar medium, and neutral intermingling or weak competing deadlock on ammonium, nitrite and nitrate agar media in all pH conditions. The late stage EP species, Coprinopsis phlyctidospora and Lyophyllum tylicolor, showed antagonistic deadlock and invaded the region containing mycelia of the non-ammonia fungi, P. citrinum and Trichoderma viride, on urea, nitrite and nitrate agar media in all pH conditions. The LP species, Hebeloma vinosophyllum, showed competing deadlock with Asp. niger and P. citrinum on urea medium and weak competition on nitrite and nitrate agar media at pH 9.0. These findings suggest that the successive occurrence of ammonia fungi is partly due to changes in the interactions between ammonia fungi and non-ammonia fungi based on changes in inorganic nitrogen. [ABSTRACT FROM AUTHOR]