DIVERSITY OF CARABIDS (ORDER: COLEOPTERA) AND SPIDERS (CLASS: ARACHNIDA) IN Bt AND CONVENTIONAL CORN CROPS IN THE CENTER OF THE PROVINCE OF SANTA FÉ, ARGENTINA
María C. Curis1*, Isabel Bertolaccini1, Alejandra Lutz1, 2, y María A. Trod2
ABSTRACT
The objective of this study was to quantify and compare the diversity of beneficial soil arthropods of Coleopteros carabidae and of the Araneae order, in conventional and Bt corn crops. Two plots of 1 ha were planted annually, one with Bt corn and another with conventional corn, in the town of Pujato Norte, department Las Colonias, Santa Fe, Argentina, between 2005 and 2010. Pitfall traps were used to capture arthropods at a capture rate of four per batch. Counts were conducted on weekly basis from sowing to harvest. The following ecological indices were estimated: relative abundance, species diversity and Shannon equity, while the Bray and Curtis index was calculated to compare the populations of the two crops. The comparisons were evaluated by a non-parametric Mann-Whitney test for paired data. No differences were found in the diversity or abundance of the Carabidae and Araneae species, or in other families of beneficial soil arthropods.
Key words: Araneae, soil arthropods, Argentina, diversity, Carabidae, Bt corn, conventional corn.
1 Facultad de Ciencias Agrarias, Universidad Nacional del Litoral, Padre Kreder 2805, Esperanza, Santa Fe, Argentina.
2 Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Av. Rivadavia 1917, Ciudad Autónoma de Buenos Aires, Argentina.
* Autor para correspondencia: [email protected]