ORGANIC MULCHING MATERIALS AS MEANS TO CONTROL INSECT PESTS AND WEEDS IN GREEN ONION (ALLIUM FISTULOSUM L.).

High damage was observed lately for green onion production in Marawi City condition. Majority of the damage was suspected to cause by an insect but was not identified. This study was carried with the following objectives: (1) assess the arthropods and weed population that can be found on the different types of mulching materials and (2) determine the relationships that exist between organic mulching materials, insect pests, insect damage and weeds in green onion. This was conducted in January to April 2018 during dry season at Plant Science Experimental Area, Mindanao State University Main Campus, Marawi City, Lanao del Sur, Philippines. Results of the study showed that Lepidopterans caused most of the damage on green onion and high on grass clipping mulches. The weed population was effectively controlled by organic mulches as of evidence of weed population decline from 42 Days After Planting (DAP) to 90 DAP. The relationship of weeds, insect damage and arthropods is more evident at 90 DAP. Hymenopterans were considered to be good natural enemies of Lepidopterans, causing significantly lowered its population, thus lowering the damage. Lepidopterans population increases with increasing sedges population, hence sedges should be controlled at early stage of the crop. Hymenopterans preferred grasses as habitat. Overall, organic mulches control the population of weeds and become the habitat of arthropods in the soil.