Studies on alternate hosts of the Asian corn borer, Ostrinia furnacalis (Guenee)

ACB alternate hosts studies from 2011-2016 were conducted at the IPB [Inst. of Plant Breeding] Experimental Station, Tranca, Bay, Laguna [Philippines] and in greenhouses inside the IPB Complex. A total of 21 weed species were surveyed from quadrants and patches. Bermuda grass (Cynodon dactulon), Cogon grass (Imperata cylindrica) and Guinea grass (Panicum maximum) were the most dominant weed species in the area. Arthopod taxa surveyed on weeds consisted of 32 families under 9 orders. Monitoring of the presence of ACB on alternate hosts showed that the most of the collected ACB were collected from the observed dominant weeds-Paragrass (Brachiaria multica), Guinea grass, Bermuda grass, and Itch grass (Rattboelia cochinchinensis). ACB was also presented in observed on alternate hosts during the dry season in the absence of the corn plant. Collection of egg masses on corn sampling. More than 700 egg masses were collected. Collection of egg masses during the dry season was relatively low since very few corn were planted at that time. Dry and wet season production of Maramias (Tripsacum laxum) showed that during the wet season planting, the plants reached an average height of 147.955 cm at 120 DAP. An average of four tillers per plant were produced. Observations from the two previous seasons showed that T. laxum do not produce seeds during dry season and only flowers when planting during wet season. ACB larval survival on Maramias showed that there was almost 100% survival of 4-day old larvae when infested on leaves and stalk. Active feeding was also observed resulting to a relative high percent damage. These observations indicate that T. laxum is a potential alternate host of the Asian corn borer.