Respiração microbiana do solo sob doses de glyphosate e de imazapyr

Microbial respiration under doses of glyphosate and imazapyr

Respiração microbiana do solo sob doses de glyphosate e de imazapyr

Microbial respiration under doses of glyphosate and imazapyr

Adailson P. de Souza^I; Francisco A. Ferreira^II; Antônio A. da Silva^II; Antônio A. Cardoso^II; Hugo A. Ruiz^III

^IProfº Adjunto do Deptº de Solos e Eng. Rural da UFPB. CEP: 58397-000, Areia/PB

^IIProfº Adjunto do Deptº de Fitotecnia da UFV. CEP: 36571-000, Viçosa/MG

^IIIProfº Adjunto do Deptº de Solos da UFV. CEP: 36571-000, Viçosa/MG

RESUMO

A degradação microbiana dos herbicidas no solo é influenciada por diversos fatores, dentre esses as características físicas e químicas do solo e da própria molécula, que agem continuamente determinando a sua magnitude. Em razão da grande variabilidade de respostas apresentadas por essas moléculas no solo e das poucas informações sobre o seu comportamento em ambientes tropicais, no que diz respeito a sua degradação, é que foi realizada uma série de experimentos, em laboratório, objetivando verificar a resposta da atividade microbiana do solo, pelo método da evolução do CO2 do solo, sob doses crescentes do glyphosate e do imazapyr (0; 4; 8 e 12 L ha^-1 do produto comercial Roundup S.Aq.C. e Arsenal 250 S.Aq.C., respectivamente), em solos de diferentes texturas e composição química, sob três conteúdos de umidade (40, 70 e 100% do equivalente de umidade). Os resultados obtidos permitiram concluir que: a) a microbiota do solo é capaz de utilizar o glyphosate e o imazapyr como fontes de carbono; b) a umidade do solo influencia a capacidade de os microrganismos degradarem o glyphosate e o imazapyr; c) a umidade de 40%, nos solos avaliados, proporcionou as menores respostas da atividade dos microrganismos, independentemente das doses dos herbicidas; e d) o efeito das doses do imazapyr sobre a atividade microbiana do solo é influenciado pelas características físicas e químicas dos solos.

Palavras chave: Atividade microbiana, biodegradação, herbicida.

ABSTRACT

The microbial degradation of herbicides in soil is affected by several factors such as the chemical and physical characteristics of the soil and the proper molecule which act continuously determining the degradation magnitude. Considering the large variability of the responses presented by these molecules in the soil as well as the scarce information about their behavior in tropical environments relatively to their degradation, a series of experiments was carried out under laboratory conditions aiming to verify the response of soil microbial activity by the soilCO2 evolution method under increasing doses of glyphosate and imazapyr (0; 4; 8 and 12 L ha^-1 of the commercial product Roundup S.Aq.C. and Arsenal 250 S.Aq.C., respectively) in soils with different textures and chemical composition under three moisture contents (40; 70 and 100% of the moisture equivalent). The obtained results allowed to conclude that: a) the soil macrobiota is able to use the glyphosate and imazapyr as carbon sources; b) the soil moisture affects the microorganisms capacity to degrade the glyphosate and imazapyr; c) the 40% moisture in the studied soils caused the lowest influenced by the soil chemical and physical responses of microorganism activities characteristics. independently of the herbicide doses; d) the effect of imazapyr doses on the soil microbial activity is influenced by the soil chemical and physical characteristics.

Key words: Microbial activity, biodegradation, herbicide.

Texto completo disponível apenas em PDF.

Full text available only in PDF format.

LITERATURA CITADA

Recebido para publicação em 06/06/98 e na forma revisada em 06/08/99.

• AISLABIE, J., LLOYD-JONES, G. A review of bacterial degradation of pesticides. Aust. j. soil res., v.33, n.6, p.925-942, 1995.
• CHOI, J.S.T., FERMANIAN, T.W., WEHNER, D.J. et al. Effect of temperature, moisture, and soil texture on DCPA degradation. Agron. j., v.80, n.1, p.108-113, 1988.
• CURL, E.A., RODRIGUEZ-KABANA, R. Microbial interactions. In: WILKINSON, R.E. (Ed.). Research methods in weed science, Atlanta: Southern Weed Science Society, 1972. p.162-194
• DICK, R.E., QUINN, J.P. Glyphosate-degrading isolates from environmentall samples: occurrence and pathways of degradation. Appl. microbiol. biotechnol., v.43, n.3, p.545-550, 1995.
• FELSOT, A.S., SHELTON, D.R. Enhanced biodegradation of soil pesticides: interactions between physicochemical processes and microbial ecology. In: LINN, D.M., CARSKI, T.H., BRUSSEAU, M.L. et al. (Eds.). Sorption and degradation of pesticides and organic chemicals in soil. Madison, Wisconsin, USA: SSSA Inc., 1993. p.227-251. (SSSA Special publication, 32)
• FLINT, J.L., WITT, W.W. Microbial degradation of imazaquin and imazethapyr. Weed sci., v.45, n.4, p.586-591, 1997.
• HEINONEN-TANSKI, H. The effect of temperature and liming on the degradation of glyphosate in two arctic forest soils. Soil biol. biochem., v.21, n.2, p.313-317, 1989.
• ISMAIL, B.S., AHMAD, A.R. Attenuation of the herbicidal activities of glufosinateammonium and imazapyr in two soils. Agric. ecosyst. environ., v.47, n.2, p.279-285, 1994.
• KISHORE, G.H., JACOB, G.S. Degradation of glyphosate by Pseudomonas sp. pG2982 via sarcosine intermediate. J. biol. chem., v.262, n.25, p.12164-12168, 1987.
• LIU, C.-M., McLEAN, P.A., SOOKDEO, C.C. et al. Degradation of the herbicide glyphosate by members of the family Rhizobiacae Appl. environ. microbiol., v.57, n.7, p.1799-1804, 1991.
• LOUX, M.M., REESE, K.D. Effect of soil type and pH on persistence and carryover of imidazolinone herbicides. Weed Technol., v.7, n.2, p.452-458, 1993.
• MADSEN, E.L. Determining in situ biodegradation: facts and challenges. Environ. sci. technol., v.25, n.1, p.1663-1673, 1991.
• MANGELS, G. Behavior of the imidazolinone herbicides in soil - A review of the literature. In: SHANER, D.L., O'CONNOR, S.L. (Eds.). The imidazolinone herbicides, Boca Raton: CRC Press, 1991. p.191-209.
• MICHAEL, J.L., NEARY, D.G. Herbicide dissipation studies in southern forest ecosystems. Environ. toxicol. chem., v.12, p.405-410, 1993.
• MOSHIER, L.J., PENNER, D. Factors influencing microbial degradation of 14C-glyphosate to 14CO2 in soil. Weed sci., v.26, n.6, p.686-691, 1978.
• NEWTON, M., HORNER, L.M., COWELL, J.E. et al. Dissipation of glyphosate and aminomethylphosphonic acid in North American forests. J. agric. food chem., v.42, n.8, p.1795-1802, 1994.
• NICHOLLS, P.H. Factors influencing entry of pesticides into soil water. Pestic. sci., v.22, n.2, p.123-137, 1988.
• PARKINSON, D., GRAY, T.R.G., WILLIAMS, S.T. Determination of microbial activity in soil. In: __________ (Eds.). Methods for studying the ecology of soil microorganisms Oxford, England: Adlard & Sons Ltd., 1971. p.71-101. (Handbook, 19)
• PAUL, E.A., CLARK, F.E. Soil as a habitat for organisms and their reactions. In: __________ (Eds.). Soil microbiology and biochemistry San Diego, California: Academic Press, Inc., 1989. p.11-31.
• PIPKE, R., AMRHEIN, N., JACOB, G.S. et al. Metabolism of glyphosate in an Arthrobacter sp. GLP-1. Eur. j. biochem., v.165, n.2, p.267-273, 1987.
• PIVETZ, B.E., STEENHUIS, T.S. Soil matrix and macropore biodegradation of 2,4-D. J. environ. qual., v.24, n.4, p.564-570, 1995.
• RAO, P.S.C., BELLIN, C.A., BRUSSEAU, M.L. Coupling biodegradation of organic chemicals to sorption and transport in soil and aquifers: paradigms and paradoxes. In: LINN, D.M., CARSKI, T.H., BRUSSEAU, M.L. et al. (Eds.). Sorption and degradation of pesticides and organic chemicals in soil Madison, Wisconsin, USA: SSSA Inc., 1993. p.1-26. (SSSA Special publication, 32)
• ROY, D.N., KONAR, S.K., BANERJEE, S. et al. Persistence, movement, and degradation of glyphosate in selected Canadian boreal forest soils. J. agric. food chem., v.37, n.2, p.437-440, 1989.
• RUEPPEL, M.L., BRIGHTWELL, B.B., SHAEFER, J. et al. Metabolism and degradation of glyphosate in soil and water. J. agric. food chem., v.25, v.3, p.517-528, 1977.
• SAKAMOTO, K., YOSHIDA, T. In Situ measurement of soil respiration rate by a dynamic method. Soil sci. plant nutr., v.34, n.2, p.195-202, 1988.
• SKIPPER, H.D., WOLLUM II, A.G., TURCO, R.F. et al. Microbiological aspects of environmental fate studies of pesticides. Weed technol., v.10, n.1, p.174-190, 1996.
• SMETS, B.F., JOBBÁGY, A., COWAN, R.M. et al. Evaluation of respirometric data: Identification of features that preclude data fitting with existing kinetic expressions. Ecotoxicol. environ. saf., v.33, n.1, p.88-99, 1996.
• SOUZA, A.P. de, LOURES, E.G., SILVA, J.F. da et al. Efeito do oxyfluorfen, 2,4-D e glyphosate na atividade microbiana de solos com diferentes texturas e conteúdos de matéria orgânica. Planta Daninha, v.14, n.1, p.55-64, 1996.
• SPRANKLE, P., MEGGITT, W.F., PENNER, D. Adsorption, mobility, and microbial degradation of glyphosate in the soil. Weed sci., v.23, n.3, p.229-234, 1975.
• TORSTENSSON, N.T.L., AAMISEPP, A. Detoxification of glyphosate in soil. Weed res., v.17, n.3, p.209-212, 1977.
• TORSTENSSON, N.T.L., LUNDGREN, L.N., STENSTRÖM, J. Influence of climatic and edaphic factors on persistence of glyphosate and 2,4-d in forest soils. Ecotoxicol. environ. saf., v.18, n.3, p.230-239, 1989.
• TORSTENSSON, N.T.L., STENSTRÖM, J. "Basic" respiration as a tool for prediction of pesticide persistence in soil. Toxic. ass., n.1, p.57-72, 1986.
• VAN LOOSDRECHT, M.C.M., LYKLEMA, J., NORDE, W. et al. Influences of interfaces on microbial activity. Microbiol. rev., n.54, n.1, p.75-87, 1990.
• WALKER, A. Herbicide persistence in soil. Rev. Weed sci., n.3, p.1-18, 1987.
• WARDLE, D.A., NICHOLSON, K.S., RAHMAN, A. Influence of herbicide applications on the decomposition, microbial biomass, and microbial activity of pasture shoot and root litter. N. Z. j. agric. res., v.37, n.1, p.29-39, 1994.
• WARDLE, D.A., PARKINSON, D. Effects of three herbicides on soil microbial biomass and activity. Plant and soil, v.122, n.1, p.21-28, 1990.

Datas de Publicação

• Publicação nesta coleção
  14 Jun 2010
• Data do Fascículo
  Dez 1999

Histórico

• Aceito
  06 Ago 1999
• Recebido
  06 Jun 1998