Glyphosate and Diuron Selectivity in Jatropha Plants When Applied with Directed Spray Technology

摘要

There is little information about the selectivity of herbicides in jatropha crops ( Jatropha curcas L.) in Brazil. The objective was to evaluate the selectivity of different rates and mixtures of glyphosate and diuron in applications with directed spray on jatropha plants under green-house conditions. A randomized block design with five replicates was used. Treatments evaluated included: Glyphosate applied alone at 720 and 1440 g of active ingredient per hectare (g ai ha^-1), diuron applied alone at 1000 and 2000 g ai ha^-1, glyphosate+diuron (720+1000 g ai ha^-1), glyphosate+diuron (720+2000 g ai ha^-1), glyphosate+diuron (1440+1000 g ai ha^-1), glyphosate+diuron (1440+2000 g ai ha^-1) and an untreated control. The application was performed at 70 days after sowing, directed spray in the lower middle third of the plants. It was concluded that diuron applied alone at 1000 and 2000 g ai ha^-1 the mixes with glyphosate (720+2000, 1440+1000 and 1440+2000 g ai ha^-1) impaired the development and photosynthetic activity of jatropha plants in applications with directed spray. Glyphosate at 720 and 1440 g ai ha^-1 and the mix glyphosate+diuron 720+1000 g ai ha^-1 showed potential good selectivity on jatropha plants in directed spray applications.