plant surface microbiology.pdf

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Giang Huong Pham et al.
reaction. No evidence for the production of basidia and basidiospores was
recorded (Fig. 3).
2.4 Other Soil Fungi
Several commonly occurring soil fungi were tested for the interaction with P.
indica. The results were highly diverse (Fig. 4). The growth of Aspergillus
sydowii, Rhizopus stolonifer, andAspergillus niger was completely blocked by
P. indica. The growth of Cunninghamella echinulata was reduced, whereas
Rhizopus oryzae, As. flavus and Aspergillus sp. completely blocked the growth
of P. indica. The data indicated that P. indica divulges a wide range of interaction
types with diverse soil fungi.
2.5 Gaeumannomyces graminis
Fig. 3. Interaction with Sebacina vermifera.
The fungal inocula were placed
on Aspergillus medium about 3 cm
apart and incubated for 5 days. The
mycelia formed a sharp demarcation
line where they touched
In his pioneering work, Dehne (1982) was able to show that AM fungi are able
to reduce soil-borne diseases and/or the severity of diseases caused by root
pathogens. P. indica was challenged with a virulent root and seed pathogen G.
graminis (Fig. 5). In a confrontational experiment, initially the mycelia were
not able to overcome each other, resulting in sharp borderlines between the
colonies. After prolonged incubation, P. indica started to invade into the area
of G. gramins and caused a lysis of the root pathogen hyphae.
In another experiment, when the P. indica was allowed to grow earlier and
the pathogen was inoculated later in the center of the solidified Aspergillus
medium, the pathogen growth was completely blocked. A culture filtrate of P.
indica also completely inhibited the growth of the pathogen. These experi-