Weed Control J 2021; 20: e202100740

Research Article

Selectivity of herbicides to sweet potato

DOI: 10.7824/wcj.2021;20:00740

Abstract

Background

In the largest areas and greater technification of the sweet potato production system, weeds are controlled with herbicides. However, there are only two herbicides registered for the crop in Brazil.

Objective

The aim of this study was to evaluate the selectivity of different herbicides for the sweet potatoes crop, depending on the genotype and dosage of each product.

Methods

Two experiments were carried out under field conditions, with the Canadense and Brazlândia Roxa cultivars, one for each cultivar. The experimental design was a randomized block, with 13 treatments and three replications. The treatments consisted of six herbicides sprayed in two doses (clomazone 0.54 and 1.08 kg ha-1, flumioxazin 0.02 and 0.03 kg ha-1, linuron 0.72 and 0.99 kg ha-1, metribuzin 0.36 and 0.48 kg ha-1, oxadiazon 0.25 and 0.50 kg ha-1 and sulfentrazone 0.25 and 0.50 kg ha-1) and a control without application. Phytotoxicity assessments, plant population, main stem length, tuberous root productivity (discarded, commercial and total) and weed control were performed.

Results

The interaction of cultivars and herbicide treatments was not significant for any trait evaluated. Among the herbicides, sulfentrazone in the highest dose was the most phytotoxic for sweet potatoes with grades of 40% to 44%. However, none of the herbicide treatments negatively affected the yield of tuberous roots.

Conclusions

The cultivars Canadense and Brazlândia Roxa have a similar response to the tested herbicides; and the herbicides clomazone, flumioxazin, linuron, metribuzin and oxadiazon are promising for use in sweet potato crop.