Herbicide Selectivity in Peanut Cultivars

Henrique Gonzalez Zanardo,Ignácio José De Godoy,Neriane Hijano,Anne Elise Cesarin,Willians César Carrega,Pedro De F R Barbosa Martins,Pedro Luis Da C A Alves

doi:10.5539/jas.v10n8p447

Abstract

Weed interference is one of the main factors responsible for reducing the productivity of the peanut crop. Among weed control methods, the chemical is considered one of the main tools, however, the herbicides registered for this crop are scarce. The objective of this study was to evaluate the selectivity of herbicides applied in post-emergence in Runner peanut cultivars. For this, an experiment was performed in an 11x5 factorial scheme, meaning 10 herbicides plus one control (without herbicide) and five peanut cultivars, with four replicates. Visual evaluations of phytointoxication were carried out at 7, 14 and 21 days after application of the herbicides. At the end of the experiment, was determined the dry mass of aboveground and root parts. Based on the results obtained, it is concluded that the herbicides 2,4-D (1.50 L ha-1), mesotrione (0.3 L ha-1), saflufenacil (0.75 L ha-1), imazapic (175 g ha-1) and S-metolachlor (1.75 L ha-1) have potential to be used for all the peanut cultivars studied. Herbicides hexazinone (2.50 kg ha-1), amicarbazone (2.00 kg ha-1), tebuthiuron (2.00 L ha-1), clomazone (2.00 L ha-1) and sulfentrazone (1.20 L ha-1) must not be indicated, at these doses, for post-emergence spraying in the evaluated cultivars. The genotypes do not react equally to certain products, therefore, there is a need for further studies the at field conditions to attest the responses obtained in the present study and verify that the yield potential is not affected.

Highlights

Peanuts (Arachis hypogea L.) are among the most important leguminous plants in the world, spotlighted as the fourth greatest oleaginous crop (Santos, Freire, & Lima, 2013)
Analyzing the interaction between herbicides for each cultivar, at 7 days after application (DAA), it was observed that, for Instituto Agronômico de Campinas (IAC) Tatu-ST, hexazinone and amicarbazone caused the highest levels of phytointoxication when compared to the control plot (Table 3)
Still at 14 DAA, a strong phytointoxication was observed in plants submitted to applications of sulfentrazone and clomazone (Table 4)

Summary

Introduction

Peanuts (Arachis hypogea L.) are among the most important leguminous plants in the world, spotlighted as the fourth greatest oleaginous crop (Santos, Freire, & Lima, 2013). Among the factors that may compromise the productive potential of the crop, the interference of weeds on the peanut plants is one of the most important. Some authors emphasized that weed infestation in peanut crops may cause reductions varying from 31 to 92% (Nepomuceno et al, 2007; Agostinho, Gravena, Alves, Salgado, & Mattos, 2006; Yamauti, Alves, Nepomuceno, & Martins, 2010), and this interference grade is dependent on cultivar, spacing, density and coexistence period, which may be modified by climate conditions and the cultural traits used (Pitelli, 1985)

Objectives

Methods

Results

Discussion

Conclusion