Controle pós-emergente de plantas daninhas em cenoura

Abstract

RESUMOO experimento foi conduzido em Piraí do Sul-PR no ano de 1995 em solo de textura argilo arenosa, tendo como objetivo avaliar a eficiência e a seletividade do herbicida propaquizafop no controle pós-emergente de plantas daninhas na cultura da cenoura. O delineamento experimental utilizado foi de blocos ao acaso com seis tratamentos e quatro repetições, quais sejam: propaquizafop (100, 125 e 150 g i.a./ha); fluazifop-p-butil (188 g i.a./ha); testemunha capinada e testemunha sem capina. A cultivar de cenoura utilizada foi Nantes Tim Tom semeada em 15 de junho, com espaçamento de 0,25 x 0,05 m, em parcelas com área útil de 5,00 x 1,00 m. As plantas daninhas predominantes foram Brachiaria plantaginea (capim-papuã), Digitaria horizontalis (capim-milhã) e Eleusine indica (capim pé-de-galinha). As avaliações foram efetuadas aos 15, 30 e 45 dias após a aplicação dos tratamentos. Observou-se que o herbicida propaquizafop, nas doses de 100, 125 e 150 g i.a./ha foi eficiente no controle sobre capim-papuã, capim-milhã e capim pé-de-galinha. O controle de plantas daninhas realizado através de herbicidas proporcionou a mesma produção obtida com o controle manual. A perda na produção ocasionada pela presença de plantas daninhas foi da ordem de 76,4%. Não foram observados efeitos fitotóxicos nas plantas de cenoura que pudessem ser atribuídos aos produtos utilizados. Palavras-chave:Daucus carota L., herbicidas, controle químico. ABSTRACTPost-emergence weed control in carrot crop. The presented field trial was conducted in 1995 in Piraí do Sul, Paraná State, Brazil, on a sand-clay texture soil, to evaluate the efficiency and selectivity of propaquizafop on carrot crop weed control. The experiment was laid out in a randomized block design with six treatments and four replications, and 5.00 x 1.00 m plots. The treatmens were: propaquizafop (100, 125 and 150 g a.i/ha); fluazifop-p-butil (188 g a.i/ha); control with weeding and control without weeding. The carrot cultivar Nantes Tim Tom was sown on June 15 with plants spaced 0.25 x 0.05 m. The prevalent weeds were Brachiaria plantaginea (capim-papuã), Digitaria horizontalis (capim-milhã) and Eleusine indica (capim pé-de-galinha). Evaluations were carried out at 15, 30 and 45 days after treatment applications. The herbicide propaquizafop, at doses 100, 125 and 150 g a.i/ha, was efficient in control of capim-papuã, capim-milhã and capim pé-de-galinha. Weed control using herbicides resulted in the same production when compared to manual control. Production losses due to the presence of weeds was 76.4%. Carrot plants did not show any visual symptoms of damage attributed to herbicide applications. Keywords: Daucus carota L., herbicides, chemical control.(Aceito para publicação em 30 de novembro de 1998) A cenoura é a principal hortaliça raiz, altamente consumida por sua riqueza em vitaminas e sais minerais. Atualmente é cultivada em grande escala, ocupando extensas áreas como em São Gotardo (MG) ou em Piraí do Sul (PR). A crescente escassez e valorização da mão-de-obra do meio rural,...

Selectivity and efficiency of herbicides in weed control on sweet sorghum

“…The average control level of U. plantaginea increased to 48.3-70 %, when s-metolachlor was applied in combination with atrazine. The difference observed between the control of U. plantaginea and D. ciliaris may be associated with their differential susceptibility to the herbicide, as it was also verified by Zagonel et al (1999), when testing the effectiveness of propaquizafop and fluazifop-p-butyl for the control of Alexander grass, D. ciliaris and Eleusine indica. It is noteworthy that the U. plantaginea seed bank was bigger than the D. ciliares one in the experimental area, what may have contributed to the reinfestation of the experimetal plots with the reduction of the herbicide residual with time.…”

Post-emergence selectivity of metribuzin to carrot

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Selectivity of Linuron Herbicide for Carrot When Sprayed in Post-Emergence

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