Differential Growth of Corn, Soybean, and Seven Dicotyledonous Weed Seedlings

Abstract

Differences in emergence, height, and leaf number between corn (Zea maysL.), soybean [Glycine max(L.) Merr.] and seven dicotyledonous weed species were measured until plants reached 15 cm in height or for 40 days, whichever occurred first, under several temperature regimes. Corn grew faster than the weeds at all temperatures. Initially soybean grew more rapidly than the weeds, but when they reached 15 cm in height the growth rate of weeds exceeded that of soybean. A positive and highly significant curvilinear relationship between plant height and leaf number was obtained for several temperature regimes for each species. Equations were derived for determining leaf number from plant height for each species.