Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Herbicide combinations for soybean (Glycine max) planted in stale seedbed.

Abstract

In field trials conducted in Louisiana during 1989-90, the effects were evaluated of non-selective herbicides (paraquat at 420 g/ha, glyphosate at 1120 g and glufosinate at 840 g), applied alone and in combination with herbicides having both foliar and soil residual activity (metribuzin + chlorimuron at 360 + 60 g, metribuzin at 420 g and imazaquin at 140 g), for weed control in soyabeans cv. Centennial, Hartz 6686, Davis, RingAround 606 and Coker 686. Echinochloa crus-galli, when 7-25 cm tall, was controlled by 48-74% with paraquat, 83-87% with glyphosate and 85-91% with glufosinate. In most cases E. crus-galli control was not enhanced by addition of the residual herbicides. When rhizome and seedling S. halepense plants were present, control with glyphosate was 96% compared with 55% with paraquat and 86% with glufosinate. Tank-mixtures of non-selective and residual herbicides generally enhanced the control of Ipomoea hederacea [Pharbitis hederacea], I. lacunosa, Sesbania exaltata (15-30 cm tall) and Sida spinosa (15-18 cm). Soyabean yields in most cases were not increased by the addition of residual herbicides. Yields following glufosinate, applied alone, were 25% greater than those following paraquat, and for all herbicide treatments yields were at least 45% greater than untreated control values.