Efeito de herbicidas residuais, aplicados por vários anos consecutivos, na distribuição do sistema radicular da laranjeira Natal (Citrus sinensis.(L.) osbeck)
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Data
1985-12-01
Autores
Victória Filho, R
Durigan, Julio Cezar [UNESP]
Andrioli, I. [UNESP]
Gusmão, E.M. [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Sociedade Brasileira da Ciência das Plantas Daninhas
Resumo
O presente trabalho foi desenvolvido com o objetivo de verificar a influência do uso contínuo de vários herbicidas residuais, sobre a distribuição das radicelas de laranjeiras Natal (Citrus sinensis (L.) Osbeck) enxertadas sobre limão Cravo (Cithus limonia Osbeck) e plantadas em janeiro de 1970. O experimento foi instalado no pomar de produção da Faculdade de Ciências Agrárias e Veterinárias do Campus de Jaboticabal (UNESP), em Latossol Roxo distrófico, com 1,6% de matéria orgânica e 51% de argila. O delineamento experimental utilizado foi o de blocos ao acaso, dentro de um esquema fatorial 11x 3x2x2, com três repetições. Os tratamentos utilizados, com as respectivas doses em kg do i.a/ha foram: fluometuron a 4,2; simazíne a 4,8; atrazine a 4,8; bromacil a 3,2;bromacil (40%) + diuron (40%) a 4,8; bromacil (53,3%) + diuron (27,6%) a 4,8; terbacil a 3,2; oxadiazon a 1,5; dichlobenil a 3,0 e 6,0; além de uma testemunha capinada. O estudo das radicel as foi feito pelo método do trado, tendo sido tomadas amostras de solo contendo radicelas, nas distâncias de 80, 160 e 240 cm do tronco, nas camadas de 0 a 15 cm e 15 a 30 cm de profundidade e em duas direções distintas (entrelinhas e entreplantas). Os resultados mostraram que as radicelas localizam-se superficialmente, com 70% delas nos primeiros 15 cm, do total encontrado na camada superficial de 0 a 30 cm de profundidade do solo. Cerca de 75% das radicelas situam-se até a distância de 160 cm do tronco. Na camada mais superficial do solo (0 a 15 cm), a quantidade de radicelas diminuiu de maneira acentuada, à medida que se afastou do tronco. Na camada de 15 a 30 cm de profundidade, ocorreu uma distribuição horizontal mais uniforme, comparada com a da camada de 0 a 15 cm. As radicelas das plantas do cultivar Natal distribuiram-se uniformemente, tanto na direção das plantas da linha vizinha, quanto nas das plantas de uma mesma linha, para o espaçamento de 7,0 m x 7,2 m. Não se detectaram diferenças estatisticamente significativas nas quantidades de radicelas entre as parcelas dos vários tratamentos com herbicidas, excluindo-se desta forma, qualquer efeito negativo de tais produtos químicos sobre o sistema radicular das laranjeiras.
This experiment was carried out at the orchard of Faculdade de Ciências Agrárias e Veterinárias - Campus de Jaboticabal - UNESP, with the objective to verify the influence of the continuous use of several residual herbicides on radicals distribution of 'Natal' orange (Citrus sinensis (L.) Osbeck) grafted on 'Cravo' lemon (Citrus Limonia Osbeck) ; they were planted on january, 1970, in a soil classified as Orthox with 1,6% of organic matter. The test had a randomized blocks experimental design in a 11 3x2x2 factorial design with three eplications. Treatments with their respe ctive doses (kg a.i/ha) were: fluometuron at 4. 2; simazine at 4.8; atrazine at 4.8; bromacil at 3.2; bromacil (40%) + diuron (40%) at 4.8; bromacil(53.3%)+ diuron (26.7%) at 4.8; terb acil at 3.2; oxadiazon at 1.5; dichlobe - nil at 3.0 and 6.0, and a control with cleaning. The study of radi cels was done by the anger method by taking soil samples containing radicels at the distances of 80, 160 and 240 cm from the trunk at layer s of 0-15 cm and 15-30 cm of depth and in two disti nct diret ions (between lines and between plants). Results showed that radicels are superficially located, being 70% of them in the layer of 0-15 cm of soil depth and the total amount of them in the layer of 030 cm of depth. About 75% of the radicels are located till a distance of 160 cm from the trunk. In the upper soil layer (0 - 15-ccm), the amount of radicels markedly decreases as increases the distance from the trunk. In the layer of 15-30 cm, there occurred an horizontal and more uniform distribution of radicels when compared with the 0-15 cm layer. No diffe rences were found for the radicels amount among the different treat ments showing that these herbicides have no negative effects on the root system of 'Natal' orange.
This experiment was carried out at the orchard of Faculdade de Ciências Agrárias e Veterinárias - Campus de Jaboticabal - UNESP, with the objective to verify the influence of the continuous use of several residual herbicides on radicals distribution of 'Natal' orange (Citrus sinensis (L.) Osbeck) grafted on 'Cravo' lemon (Citrus Limonia Osbeck) ; they were planted on january, 1970, in a soil classified as Orthox with 1,6% of organic matter. The test had a randomized blocks experimental design in a 11 3x2x2 factorial design with three eplications. Treatments with their respe ctive doses (kg a.i/ha) were: fluometuron at 4. 2; simazine at 4.8; atrazine at 4.8; bromacil at 3.2; bromacil (40%) + diuron (40%) at 4.8; bromacil(53.3%)+ diuron (26.7%) at 4.8; terb acil at 3.2; oxadiazon at 1.5; dichlobe - nil at 3.0 and 6.0, and a control with cleaning. The study of radi cels was done by the anger method by taking soil samples containing radicels at the distances of 80, 160 and 240 cm from the trunk at layer s of 0-15 cm and 15-30 cm of depth and in two disti nct diret ions (between lines and between plants). Results showed that radicels are superficially located, being 70% of them in the layer of 0-15 cm of soil depth and the total amount of them in the layer of 030 cm of depth. About 75% of the radicels are located till a distance of 160 cm from the trunk. In the upper soil layer (0 - 15-ccm), the amount of radicels markedly decreases as increases the distance from the trunk. In the layer of 15-30 cm, there occurred an horizontal and more uniform distribution of radicels when compared with the 0-15 cm layer. No diffe rences were found for the radicels amount among the different treat ments showing that these herbicides have no negative effects on the root system of 'Natal' orange.
Descrição
Palavras-chave
herbicide s, root system, Natal orange, Herbicidas, Sistema radicular, laranja Natal
Como citar
Planta Daninha. Sociedade Brasileira da Ciência das Plantas Daninhas , v. 8, n. 1-2, p. 81-96, 1985.