Um seletividade e eficiência de herbicidas em pós-emergência inicial em sorgo granífero

Abstract

Grain sorghum (Sorghum bicolor L.) has few molecules registered for use in its production system. This study aimed to evaluate the selectivity of different promising herbicides in the initial post- emergence of grain sorghum crops. The experiment was conducted in the field, in a completely randomized design, with four replications. The herbicides tested were terbutylazine (1,000 g a.i. ha⁻¹), 2,4-D (1,209 g a.i. ha⁻¹), ametrine (1,000 g a.i. ha⁻¹), mesotrione (96 g a.i. ha⁻¹), bentazone (420 g a.i. ha⁻¹), nicosulfuron (45 g a.i. ha⁻¹) and saflufenacil (35 g a.i. ha⁻¹), in addition to a control without herbicide. The results showed that terbutylazine and bentazone were selective, without causing injury or delaying crop development. The 2,4-D, at the dose tested, was not selective, causing significant injuries. Nicosulfuron led to plant death 28 days after application, while the other herbicides also showed low selectivity. It was concluded that terbutylazine and bentazone, at the doses tested, were the only selective herbicides for sorghum crops, not interfering in its development and providing good weed control.