Effects of clomazone formulations at the initial development of Jatropha curcas

Abstract

Competition with weeds is one of the obstacles to achieve high yields in jatropha harvest. The chemical method is an alternative weed control due to its high efficiency, readiness and economy, when compared to other methods. However, products recommended for this crop are scarce. This study aimed at evaluating the effects of pre and post-emergence clomazone formulations at the initial development of jatropha. Two experiments were conducted under a randomized blocks design, in a 2 x 5 factorial arrangement, with four replications, consisting of the combination of two clomazone formulations (encapsulated suspension and emulsifiable concentrate) and five doses (0 g ha-1, 250 g ha-1, 500 g ha-1, 1,000 g ha-1 and 2,000 g ha-1). The dry matter of the plants was reduced both in the pre-emergence and post-emergence applications. Net photosynthesis was not affected by the application of clomazone in both formulations. The encapsulated suspension formulation is less phytotoxic than the emulsifiable concentrate formulation for pre and post-emergence applications. However, both formulations negatively affect the early development of jatropha plants.

Dynamics of Clomazone Formulations Combined with Sulfentrazone in Sugarcane (Saccharum spp.) Straw

“…Differences in the selectivity among clomazone formulations were reported for different crops [19,33]. A higher selectivity is attributed, in general, to application of microencapsulated formulations of clomazone, which is explained by the slow release of the clomazone molecule [19].…”

Dynamics of Clomazone Formulations Under Different Applications Conditions

“…Differences in the selectivity of clomazone formulations have been reported in several crops, such as maize, sorghum and rice (Schreiber et al, 2015), physic nut (Berté et al, 2015) and cassava (Scariot et al, 2013). In general, the greater selectivity of the microencapsulated formulation for the crops has been attributed to the slow release of the clomazone molecule.…”

“…Schreiber et al (2015) found that the microencapsulated formulation of clomazone resulted in lower phytotoxicity to bioindicator species, because it is less volatile. Likewise, there was greater selectivity in the microencapsulated formulation of clomazone in several crops, such as maize, sorghum, rice (Schreiber et al, 2015), physic nut (Berté et al, 2015) and cassava (Scariot et al, 2013). In general, the lower phytotoxicity of a microencapsulated formulation has been attributed to the slow release of the active ingredient by the microcapsule.…”