plant surface microbiology.pdf

30 Axenic Culture of Symbiotic Fungus Piriformospora indica 599
fer 1977) was the best. However, other media were helpful in carrying out several
physiological and molecular experiments (see Chap. 15, this Vol.).
Figure 6 shows typical growth on solidified aspergillus medium after 28 days.
Rhythmic growth was often recorded. The mycelium stopped its growth for
some time and produced a large number of chlamydospores of different
dimensions. After 24–48 h, the mycelium started its growth again, producing
normal amount of chlamydospores. This resulted in the formation of rythmic
rings. The physiological reason for this phenomenon is not yet known,
although this tendency has been recorded for several other members of
Basidiomycetes. The fungus grows profusely upon shaking broth aspergillus
medium. The temperature range of the fungal growth is 25–35 °C; the optimum
temperature and pH being 30 °C and 5.8 (4.8–6.8), respectively. Figure 7
gives a view of the cultivation on broth media. Colonies were large and small
depicting sea urchin-like radial growth. The maximum surface growth was
recorded after 10 days. The colony diameter is indicated in Fig. 8. The fungal
biomass is indicated in Table 2. The optimum growth was recorded after 5
Fig. 5. P. indica was
grown on the following
solidified media. a MS,
b WPM, c MMN, d M4N,
e PDA, f aspergillus