Abstract

CAFFARINI, Patricia et al. EFFECTS OF ACETONIC AND WATER EXTRACTS OF RICINUS COMMUNIS, MELIA AZEDARACH Y TRICHILLIA GLAUCA ON BLACK COMMON CUTTING ANT (ACROMYRMEX LUNDI). Idesia [online]. 2008, vol.26, n.1, pp. 59-64. ISSN 0718-3429.  doi: 10.4067/S0718-34292008000100008.

Leaves cutting-ants are important pest in agroforestry. Many plant species are studied in order to replace synthetic pesticides, since they can produce behavior changes or toxic effects on the ants and on its symbiotic fungus. In lab trials, with the black common cutting ant, its response to acetone and water extracts of M. azedarach, T. glauca, and R. communis was assayed. In artificial nest (n=3) without chance of choice, they were offered pieces of eucalyptus leaves with extracts applied on. Carrying time by treatment was registered. Pieces with ricinus and melia (acetone and water extracts) were the least accepted -highest repellency effect- according to Friedman tests (water T²=85, p=0,0001; acetone T²=5,50, p=0,0371). However, water extracts performed a most definite separation within. Then, toxic effects for ingestion from acetone extracts were tested in vitro. In Petri dishes, acetone extracts in basic diet were offered to the ants (n=5) and daily survivors were registered. Weibull function was adjusted to obtain α (mean rate of mortality) and β (daily survivorship); besides, maximum longevity was compared by means of ANVA and Tukey. Both analysis obtained the same results, and trichillia extract -the least repellent- caused the highest toxic effect. That suggests taking advantage of both outdoors, and to integrate the repellent effect of ricinus in the crops and the toxic effect of trichillia in nests.

Keywords : ricinus; melia; trichillia; black cutting ant.