Preliminary bioassay studies under laboratory condition identified
Beauveria bassiana strain, Bb 101-OFL as a potential fungal isolate for the
control of the Asian corn borer, Ostrinia furnacalis Guenee. This B.
bassiana strain caused up to 90% ACB mortality at a dose of 1 x
109
spores/ ml. The effectiveness of B. bassiana Bb 101-OFL under field
condition was assessed in combination with other cultural practices such as
planting distance of glutinous white corn as determined by the agronomic
and yield responses and the yield of glutinous white corn. The laboratory
experiment was done in UPLB while the field experiment was undertaken
at the RET Experimental Farm, CLSU from March to August 2011 and
June to September 2011, respective ly.The treatments in the field
experiment were distance of planting as the main plot (60 x 10, 60 x 20
and 60 x 30 cm) and use of biocontrol agents (B. bassiana and Bacillus
thuringiensis) as the subplots in comparison with the standard check and
control following the split plot experiment in Randomized Complete Block
Design with three replications. Results from the field screening showed
more ACB in corn plots planted at a planting distance of 60 cm x 20 cm.
Other parameters such as entrance hole and tunnel count were not affected
by the different distances of planting. In terms of ear characteristics,
significantly longer (16.99 cm), bigger (4.08 cm) and heavier (122.81g)
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ears were noted in corn plots with 60 cm x 30 cm planting distance
whereas the lowest plant survival as well