Abstract:
Trichoderma harzianum
(T39),
T.virens
(DAR74290),
T.viride
(MO),
T. harzianum (
M)
and TrichderminB a commercial formulation of
T.
harzianum(Bi) were evaluated as
potential biological agents for the control of charcoal stem rot in melon caused by
Macrophomina phaseolina.
Cell-free metabolites of
T. harzianum
(M),
T. harzianum
(T39)
and
T. virens
(DAR 74290) inhibited growth of
M. phaseolina
completely
in vitro
and
appeared to be fungicidal.
T. viride
(MO)
inhibited fungal growth from 34.9% to 71%.
T.
harzianum
(T39),
T. harzianum
(M),
T. virens (
DAR 74290),
T. viride(
MO)
and
T.
harzianum (
Bi) were tested for their ability to pr
otect melon plants from disease caused
by
M. phaseolina
in a glasshouse experiment. The percentage of stand plants with the
antagonist alone or in combin
ation with the pathogen was si
gnificantly (p<0.05) greater
than in plants inoculated with the pathogen alone. The percentages for the stand plants in
treatments were as follows:
T. harzianum
(T39),
T. harzianum
(M),
T. virens
(DAR 74290),
M. phaseolina, M. phaseolina + T. virens (
DAR 74290),
M. phaseolina + T. harzianum
(
T39) and
M. phaseolina + T. harzianum
(M),at 95, 100, 97.5, 15,
64.25, 75.25 and 47.55
percent respectively. The percentage for the stand plant in the
commercial
Trichodermin
B +
M. phaseolina
treatment
(96.7%) was greater than for
M. phaseolina
alone (46.7%)
and demonstrated the best result in the control of charcoal stem rot in melon.
