The research was conducted to study an efficacy of the fungus
Trichoderma harzianumin controlling the gray mold disease on
tomato that causing by the fungus Botrytis cinerea. A local isolate
of the fungus T. harzianum was studied under laboratory conditions
using two methods: antagonism and the spore suspension.
It was detected for the ability of a local fungus T.harzianum and A.alternate which
was isolated from the rhizosphere of Wheat plant Triticum aestivum L. to produce the
enzyme complex cellulase in solid medium (CMC-Agar). So it has been showed that
T.harzianum and A.alternate have an ability to produce this enzyme, While the
T.harzianum have higher production of cellulase than A.alternate. Then conducted a
quantitative test using Mandelium liquid medium is used to determine the optimal
conditions (incubation time, temperature, PH) for the best cellulase production of the two
fungus studied. It was, the best conditions for its production, from T.harzianum is 7 days
inchubation (3.97 U/mL), temperature 26C (4.07 U/mL) and pH=5.5 (4.19U/mL). While
the best conditions for its production from A.alternate is 8 days inchubation (3.29U/mL),
temperature 28C (3.15 U/mL) and pH=5.0 (3.86 U/mL). The comparison between the
enzymatic activity average for both fungus , was showed superiority T.harzianum by
production cellulase than fungus A.alternate. And discern that the effect of the incubation
time on cellulase production from fungus T.harzianum more than its effect on cellulase
production from fungus A.alternate. While effect of pH and temperature on cellulase
production from fungus T.harzianum less than their effect on cellulase production from
fungus A.alternate.
The antagonistic activity of liquid culture filtrate of Trichodermaharzianum at
different concentrations (5, 10, 20 and 30%) was evaluated "in vitro" at 25 C° against
following plant and human pathogenic fungi: Aspergi
llusniger, Rhizopusstolonifer,
Fusariumoxysporum, F.moniliforme, Alternariaalternata and Candida albicans.
The results showed high level activity of culture filtrate inhibiting the growth of
tested fungi.
The activity was varied with the different species of fungi and the different
concentrations of culture filtrate. The highest activity was against fungus A.niger which
showed precent inhibition equal 96.3% at 30% concentration. Whereas the lowest
inhibition percentage to 77.6% was recorded for fungus A.alternata in comparison with
other fungi.
The culture filterate was not affected the radial colonies growth of R.stolonifer at 5%
and 10% concentrations, however the colonies was fragile and weak, and clearly inhibited
the spores formation.
The culture filtrate was showed high antagonistic capability against the human
pathogenic fungus C.albicans, and the radial inhibition growth was 1.38 cm at 30%
concentration.
45 samples were collected from various sources (soil, degraded wood and
mushroom compost) from three cities (Damascus, Homs and Lattakia). 18
Trichoderma isolates were isolated and identified by microscope. These isolates
were screened using CMC m
edium with Congo red dy to identify their ability
to produce cellulase complex. The amount of enzyme production was
determined depending on the radius of clear zone around the colony. Results
showed that the most productive isolate was Tr with radius 7 ± 0.2 cm followed
by Tg and Ti. Optimization of cellulase production was performed using
response surface methodology (RSM). The optimal parameters were:
temperature 29.5 ˚C, pH = 6، incubation time 4 days, aeration speed 175 rpm
and wheat straw concentration 3%. All studied parameters had significant
effect on cellulase enzyme activity.
