Initial growth of Jatropha curcas L. under phosphorus doses and glyphosate drift

Abstract

The objective of this study was to evaluate the initial growth of jatropha (Jatropa curcas L.) plants under the effect of phosphate fertilization and simulation of glyphosate drift. The experiment was conducted using plastic vessels, conditioned under field conditions. A randomized block design, in a 3 x 5 factorial scheme, three doses of phosphorus (0, 40 and 80 kg ha-1 of P2O5) and five doses of glyphosate (0, 1.1, 3.3, 10 e 30 g ha-1) with four replicates. Leaf area, total dry matter, lignin and cellulose content, foliar phosphorus content, and gas exchange were evaluated. It was concluded that fertilizations from 40 kg ha-1 presented on average the largest increases in: leaf area; total dry matter; phosphorus content and for liquid photosynthesis. The simulation doses of glyphosate drift above 30 g ha-1 may impair the growth of jatropha plants considering the following variables: total dry matter, lignin content and cellulose and protein. Phosphate fertilization may render jatropha plants tolerant to glyphosate drift simulation doses.