Using imidazolinone to alter sorghum row configuration post sowing, Mungindi 2021–2022

Abstract

Key findings •Establishing a target population yielded significantly more than establishing double the population and then spraying 50% of the plants out at 7 leaf stage. For example, sowing a population of 30,000 plants/ha and then reducing the population to 15,000 plants/ha yielded about 30% less than establishing 15,000 plants/ha initially. •Biomass production and grains per unit area were strong indicators of yield. •In years of above average rainfall and good starting soil moisture, reducing the population and changing the row configuration post emergence with an imidazolinone herbicide is not suggested due to the yield penalty incurred. •Using an in-crop imi herbicide was effective in reducing plant population and altering row configuration.