Selectivity and efficacy of herbicides to control volunteer soybean in castor crop

Abstract

Castor bean is an alternative to many grain production areas, mainly as crop for the second season after soybean. In this scenario, there is demand for research on management of plants, resulting from remaining seeds of soybean after harvest. The objective of this work was to evaluate the selectivity and efficacy of post-emergence herbicides for the control of volunteer soybean in the castor crop. Two greenhouse experiments were carried out in a completely randomized design with four replications. The first assay was focused on the selectivity of herbicides to the castor crop, and the second to the efficacy of herbicides for soybean con trol. Evaluation of herbicide selectivity for the castor cultivar BRS Energia was carried out at 4 to 6 true leave stages. The treatments corresponded to two doses of ethoxysulfuron, halosulfuron-methyl, iodosulfuron-methyl, ioxynil, metamitron, oxadiazon and a control without any application. To evaluate the control efficacy of soybean cultivar BRS 3280RR in 3 trefoil stage, the treatments were comprised of two doses of ethoxysulfuron, halosulfuron-methyl, metamitron and a control without application. The evaluations were: control, phytointoxication and plant height at 7, 14 and 21 DAA; stem diameter, leaf area, dry mass of aerial part and roots at 21 DAA. The results showed that herbicides ethoxysulfuron (60 and 80 g ha ) and halosulfuron-methyl (75 and 112.5 g ha -1) were effective for the volunteer soybean control.

Selectivity of Pre and Postemergence Herbicides in Single or Combined Applications in Castor Crop

“…In the present study, the selectivity of metamitron, ethoxysulfuron, and halosulfuronmethyl was confirmed in the field as they did not interfere with height at 35 DASPA and primarily affected grain yield. Almeida et al (2018), when applying the same herbicides and doses at the stage of four to six true leaves, also did not observe reduction in the initial development of castor [28]. According to the authors, halosulfuron-methyl and ethoxysulfuron were the best options for the control of volunteer soybean in castor crop.…”

“…For the control of broadleaf weed species, the herbicide chlorimuron-ethyl is considered the only selective latifolicide for use in postemergence of castor crop [15,16,27]. Recently, the herbicides halosulfuron-methyl and ethoxysulfuron have emerged as possibilities for postemergence control of sedges and volunteer soybean (Glycine max) in areas where castor can be used in crop succession systems [16,28].…”

Crescimento inicial do melão após aplicação de herbicidas em pós-emergência

“…A diminuição e posterior paralisação do crescimento das plantas são consequências da ação desses herbicidas inibidores Protoporfirinogenio Oxidase, pois a inibição dessa enzima contribui para a redução da produção de clorofila (Silva et al, 2007). Nosratti et al (2017) crescimento, altura das plantas e área foliar na cultura da mamona (Almeida et al, 2018).…”