CEPAVE   05420
CENTRO DE ESTUDIOS PARASITOLOGICOS Y DE VECTORES
Unidad Ejecutora - UE
artículos
Título:
Impact of glyphosate on the development, fertility and demography of Chrysoperla externa (Neuroptera: Chrysopidae): Ecological Approach
Autor/es:
SCHNEIDER, MARCELA INÉS; SANCHEZ, NORMA ELBA; PINEDA, SAMUEL; CHI, HSIN; RONCO, ALICIA
Revista:
CHEMOSPHERE
Editorial:
Elsevier
Referencias:
Año: 2009 vol. 76 p. 1451 - 1455
ISSN:
0045-6535
Resumen:
Few ecotoxicological studies have used life table analysis to evaluate the toxicity of pesticides on beneficial organisms. This study is the first report of the effect of the herbicide glyphosate on a predator insect, Chrysoperla externa, using a demographic approach. This predator is associated to soybean pests and has a potential role as a biological control agent in the Neotropical Region. The objective of this work was to evaluate the side effects of glyphosate on the development, fertility and demography of C. externa, treated orally by ingestion of glyphosate-dipped eggs of S. cerealella in laboratory conditions. The data were analyzed using the age-stage, two-sex life table. Development from third larval instar to pupae and adult longevity were shorter in glyphosate-treatment than in the control. Adult pre-reproductive period was longer in glyphosate-treatment than in the control. Fecundity and fertility were deeply reduced, as well, being fertility greater affected. A high important reduction was registered in all population parameters. Most eggs from glyphosate-treated cohort looked abnormal, smaller than control, dehydrated and became black two days after oviposition. In addition, adults developed tumours in the abdomen region at 20 days after emergence, being the effect more drastic in females than males. It is beyond the scope of our study to speculate on the effects of this herbicide on C. externa field populations. However, it seems likely that populations under continuous use of glyphosate would be exposed at greater detrimental effects in the long term.