Fig.3-7 Morphology of C100, ΔMareA and OE-MareA in mycelium from different nitrogen sources
3.2.5 Morphological analysis of mycelium and spores under scanning
electron microscope
In PDA medium, the mycelium of C100 exhibited a lamellar shape, while
the spores showed folds. The ΔMareA mycelium and spore surface
were smooth. The OE-MareA mycelium collapsed severely, and the
spores had depressions in the middle. Under PDA-Gln culture conditions,
both C100 and ΔMareA mycelia were columnar with an uneven spore
surface. On the other hand, OE-MareA showed a lamellar shape with
a flatter and smoother spore surface. When grown on
PDA-(NH4)2SO4 medium,
both C100 mycelium and spores had full and smooth surfaces. However,
ΔMareA and OE-MareA spores were collapsed to varying
degrees. Under PDA-NaNO3 medium condition, C100 mycelium
was cylindrical with a non-smooth surface. ΔMareA mycelium was
flaky and twisted, while OE-MareA mycelium was very smooth.
Additionally, the volume of C100 and ΔMareA spores was smaller
than that of OE-MareA . In PDA-Urea medium, the mycelium of C100
was smooth but slightly depressed, ΔMareA mycelium and spores
were smooth and full with relatively small volumes, whereas
OE-MareA displayed a rough lamellar surface for its myelum along
with fuller-spored characteristics. Overall, the AreA gene had an
effect on the growth and morphology of mycelium and spores, but had
little impact on their thickness and size. The most significant
difference between the three strains was observed when Gln and
NaNO3 were used as nitrogen sources. As shown in Figure
3-8.