The economic threshold determinants for the Asian corn borer, Ostrinia furnacalis (Guenée) were defined over several croppings. The relations between leaf injury, larval equivalents and the corresponding yield losses were established. The larval equivalents did not necessarily follow the increase of the leaf injury rating during the late whorl stage. Leaf damage and the larval equivalents correlated well with yield loss. Using the number of larvae per plant as parameter based on current prices of corn and other inputs, an ETL of not more than one larva/plant was established. The egg mass density, larval population and egg mass frequency indices were positively correlated, especially at their respective peak densities. LIR or leaf damage, number of larvae per plant and the frequency index of egg masses were indicated as good determinants of the ETL, with the egg mass frequency as most practical and convenient for use by farmers.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.