2.3. Screening experiments
2.3.1. Inoculation
Two screening experiments were conducted in a greenhouse to
evaluate the ability of the ten isolates/strains to endophytically colonize
cassava plants; one with the five B. bassiana isolates/strains
and one with the five M. anisopliae isolates/strains. Each treatment
consisted of 12 cassava plants, which were grown and prepared
for inoculation according to the methods outlined above at 2.1. Each
cassava plant root area was drenched with 100 mL of inoculum,
applied to the soil surface around the base of the plant 14–15 days
after the cassava cuttings were planted in the pots. At this time,
the buds on the cutting of the cassava plants had already produced
roots and shoots. Control plant pots were inoculated with 100 mL
of sterile distilled water containing 0.1% Triton X-100. The plants
were arranged in the greenhouse in a randomized block design with
12 blocks, each block containing six plants (five treatment plants
and one control). A root drench was chosen as the best inoculation
method after concluding a pilot study comparing root drench to
immersion of cuttings. The immersion method involved the immersion
of 200 mm long cassava stem cuttings in fungal inoculum for up
to 2 h prior to planting the cuttings. However, this method resulted
in only one root subsequently being colonized by B. bassiana and no
roots colonized by M. anisopliae