VOLUME 18 (Supplement)

Potential reduction of chemical fertilizer use by applying Trichoderma microbial inoculant (TMI) in UPLB Lagkitan variety native corn cropping

Field trials were conducted for two seasons to evaluate the effects of Trichoderma microbial inoculant (TMI) as biofertilizer and biocontrol agent for fall armyworm (FAW- Spodoptera frugiperda) in corn. Six treatments with four replicates were arranged in a randomized complete block design. Mean yields during the wet season for T1 (full dose recommendation, chemical fertilizer (CF) and T2 (TMI + ½ recommended rate CF) did not differ significantly at 3.44 t ha^-1 and 2.94 t ha^-1, respectively. Dry season mean yields of T1 and T2 plots were equal. During the wet season, T2 had significantly fewer larvae than T1 and was not significantly different from T5 (full dose CF, insecticide). The damaged hills in T2 were 41% lower than in T1, although this difference was not statistically significant. The chemical insecticide (T5) effectively lowered FAW damage but reduced damage did not increase corn yield. Yield from the dry season was severely reduced at 0.33 t ha^-1 for T1 due to unfavorable weather conditions. Continuous rain resulted in an average of 4.5 sunshine hours and waterlogged soil conditions. Yield data from dry and wet seasons cropping suggest that TMI has the capability to reduce use of chemical fertilizers in corn. FAW incidence in dry season cropping showed no significant differences among the treatments probably due to extremely low grain yield. Control of FAW using TMI was not conclusively demonstrated although results of the wet season cropping showed TMI potential as a FAW biocontrol agent. These results merit further verification with trials in corn-producing provinces.