Antifungal activity of non-volatile metabolites
of T. harzianum
Fig. 2 shows that T. harzianum metabolites completely
inhibited B. oryzae mycelial growth.
Light Microscope observation of T. harzianum
mycoparasitism
Light microscopic observations showed no evidence
of mycoparasitic behavior of the tested isolate of
T. harzianum against B. oryzae where the hyphae
intermingled.
SEM observation of T. harzianum mycoparasitism
T. harzianum mycoparastism on B. oryzae was
further investigated by scanning electron microscopy
(SEM) to confirm the light microscopy results. Fig. 3
is an example of the SEM observations, which also
showed no evidence that mycoparasitism contributed
to the aggressive nature of the tested isolate of
T. harzianum against B. oryzae.
Field evaluation of the biological agent against
the brown spot disease
Field application of T. harzianum spore sprays was at
104, 106 , and 108 spore ml1. No significant differences
were recorded in plant height, panicle length,
or number of panicle branches between the treated
and the untreated rice plants (data not shown