Published online by Cambridge University Press: 12 June 2017
Soil-applied imazaquin or chlorimuron plus metribuzin reduced ivyleaf morningglory photosynthetic rate, leaf area, biomass, and seed production per plant compared to the nontreated control. Photosynthetic rate of ivyleaf morningglory was reduced a minimum of 53%, and total leaf area was reduced at least 67% with either herbicide, regardless of ivyleaf morningglory densities. Ivyleaf morningglory biomass and seed production were reduced at least 62% with either herbicide across all ivyleaf morningglory densities. Soybean leaf area, photosynthetic rate, and biomass were not affected by herbicide treatment or ivyleaf morningglory densities of 2, 4, 6, or 8 per m of row.