Agronomic performance of canola submitted to desiccation with herbicides at different maturation stages/ Desempenho agronomico de canola submetida a dessecacao com herbicidas em diferentes estadios fenologicos da maturacao

• Published in: Revista brasileira de engenharia agrícola e ambiental 2019-06, Vol.23 (6), p.419
• Main Authors: Rosa, Willian B, Duarte, Jose B., Jr, Perego, Ivonei, de Almeida, Bruno H, da Costa, Antonio C.T, Tomm, Gilberto O
• Format: Article
• Language: Spanish
• ISSN: 1415-4366
• DOI: 10.1590/1807-1929/agriambi.v23n6p419-424

Uneven maturation in canola is an important challenge for its management in regions subject to frost and high rainfall at the end of the cycle. In order to identify practices to maximize grain yield under these growing conditions, this work evaluated the effects of desiccation with herbicides at different phenological stages on Hyola 433, one of the most commonly used hybrids in Brazil. The experiment was conducted in a randomized block design with four repetitions in a 6 x 4 factorial scheme, with five herbicides: paraquat, diquat and ammonium glufosinate at dose of 400 g a.i. [ha.sup.-1], glyphosate at 1,440 g a.i. [ha.sup.-1] and saflufenacil at 70 g a.i. [ha.sup.-1], plus the control, at four phenological stages of silique maturation ([G.sub.2], [G.sub.3], [G.sub.4] and [G.sub.5]). Desiccation at [G.sub.2] and [G.sub.3] reduced the oil content and thousand-grain weight on average by 60%, affecting directly grain yield. Desiccation at [G.sub.4], regardless of herbicide, did not influence thousand-grain weight and oil content, but the use of diquat reduced canola yield by 187 kg [ha.sup.-1]. In the desiccation at [G.sub.5], none of the herbicides led to differences compared to the control for thousand-grain weight, yield and oil content, and it allowed harvest to be brought forward by five days. In general, the crop presents adequate responses to the desiccation with different herbicides at the phenological stages [G.sub.4] and [G.sub.5]. Key words: harvest antecipation, grain yield, oil content A desuniformidade na maturacao da canola constitui importante desafio para o manejo da cultura nas regioes sujeitas as geadas e/ou as elevadas precipitates no final do ciclo. Visando identificar praticas para maximizar o rendimento de graos sob estas condicoes de cultivo, este trabalho avaliou os efeitos da dessecacao com herbicidas em diferentes estadios fenologicos sobre Hyola 433, um dos hibridos mais empregados nas lavouras do Brasil. O experimento foi conduzido num delineamento de blocos casualizados, com quatro repeticoes, em esquema fatorial 6 x 4, sendo cinco herbicidas: paraquat, diquat e glufosinato de amonio na dose de 400 g i.a [ha.sup.-1], glifosato com 1.440 g i.a [ha.sup.-1] e saflufenacil dosado em 70 g i.a [ha.sup.-1], mais a testemunha, em quatro estadios fenologicos da maturacao das siliquas ([G.sub.2], [G.sub.3], [G.sub.4] e [G.sub.5]). A dessecacao em [G.sub.2] e [G.sub.3] reduziu 60% em media o conteudo de oleo e a massa de mil graos, impact