DISCUSSION
As shown in Table 1, all applied treatments of
Trichoderma either separately or in combination could
control against F. oxysporum and Fusarium solani and
wilt and root rot of tomato fields. Plants treated one
week before inoculation with the pathogen, appeared
healthy and with no wilting or root rot symptoms. Wilt
can be observed within 25 days of sowing into infected
soil (Nene et al.,1978). Wilting may also occur in adult
plants up until the reproductive and podding stage.
Drooping of the petioles, rachis and leaflets in the upper
part of the plant, together with the pale green colour of
the foliage, are the most common symptoms. Often
within 2 to 3 days the entire plant is affected (Haware et
al., 1986). Lower leaves also become chlorotic. When
uprooted before completely dried, affected plants show
no external root discolouration. However, internal
discolouration may be seen extending up towards the
stem. Internal discolouration is due to infection of the
xylem tissues of the root and stem. Transverse sections
of the infected root examined under the microscope
show the presence of hyphae and spores of the fungus
in the xylem. This is a diagnostic feature of Fusarium
wilt. In certain ctomato cultivars typical symptoms may
not develop. Instead, there is a yellowing and drying of
the lower leaves, and a stunting of the plant. Roots will
show internal discolouration.