Summary• Variation in endophytic fungal diversity closely associated with roots, stems and leaves of common reed ( Phragmites australis ) is reported here at sites with different oxygen conditions.• Fungi isolated from surface-sterilized reed tissue were identified and characterized by morphological and molecular methods including internal transcribed spacer (ITS) sequence analysis from two dry and two flooded sites at Lake Constance (Germany).• Most isolates were ascomycetes, some basidiomycetes. There were differences in distribution between dry and flooded sites. Trichoderma sp. and Cylindrocarpon sp. were almost exclusively recovered from roots of reed growing at dry sites, whereas Microdochium sp. and Cladosporum sp. were more frequently found at flooded sites. The preference of Trichoderma sp. for drier sites was confirmed by a nested PCR assay targeting the variable ITS region.• A diverse assemblage of endophytic fungi that differ in distribution between aerated and nonaerated soils is found in reed habitats. The rich mycoflora associated with roots in completely anaerobic soils might depend on downward oxygen transport via an aerenchyma-based ventilation system.

Leibinger, W., Breuker, B., Hahn, M., and Mendgen, K. 1997. Control of postharvest pathogens and colonization of the apple surface by antagonistic microorganisms in the field. Phytopathology 87:1103-1110. Selected isolates of Aureobasidium pullulans, Rhodotorula glutinis, andBacillus subtilis reduced the size and number of lesions on wounded apples caused by the postharvest pathogens Penicillium expansum, Botrytis cinerea, and Pezicula malicorticis. Combinations of the antagonistic microorganisms were applied to apple trees in the field late in the growing season of two consecutive years. The population dynamics of the introduced microorganisms and the incidence of fruit decay were determined. Population sizes of introduced antagonists on apple surfaces increased in the field following application of treatments until harvest. After transfer of the fruit from the field into cold storage, the populations of the introduced antagonists remained higher than in the control treatments. Identification of the applied isolates of A. pullulans and R. glutinis during the experiments was achieved by isolate-specific DNA probes generated from random amplified polymorphic DNA. A combination of two strains of A. pullulans and one strain of R. glutinis suppressed rotting of apple to the same extent as the commonly used fungicide Euparen. Our data demonstrate that the application of antagonistic microorganisms in the field represents a promising alternative to fungicide treatments to control postharvest diseases of apple.