versão impressa ISSN 0120-9965
SALAZAR G., Claudia e BETANCOURTH G., Carlos. Evaluation of plant extracts for Guatemalan potato tuber moth (Tecia solanivora) management in potato crops in Nariño, Colombia. Agron. colomb. [online]. 2009, vol.27, n.2, pp. 219-226. ISSN 0120-9965.
The Guatemalan tuber moth (T. solanivora) causes serious harm to potato crops, affecting their quality and reducing their productivity. Seeking to contribute to the knowledge about the control of this plague, a series of plant extracts were tested for their efficacy in reducing the harm it causes on the crop. The field tests were conducted in two different research sites in the municipalities of Pasto and Contadero, (Nariño, Colombia), by means of a random block design with four repetitions in each locality. The treatments were: alisin® (garlic + hot pepper extracts, 400 cm3/200 L of water); eucalyptus extract (3,000 cm3/200 L of water); rue extract (3,000 cm3/200 L of water); absolute control and commercial control (Permetrin 300 cm3/200 L of water). A Tukey significance test and an analysis of variance were applied to assess yield, as well as harm caused by the insect. In Contadero, those treatments applying eucalyptus, permetrine and alisin showed significant differences (average yield scores ranging between 18.05 and 24.90 t ha-1) when compared to rue and the absolute control (16.7 and 8.0 t ha-1, respectively). Regarding harm in this same site, the absolute control treatment showed highly significant differences (51.42%) with respect to Alisin (27.82%), and permetrine (27.62%). Highly significant differences were also found in Pasto among the yield scores obtained with applications of eucalyptus, alisin, permetrine, rue and the commercial control (values ranging from 22.9 to 10.7 t ha-1). The least harm produced by the pest in this same locality was attained with permetrine, which showed significant differences with all other treatments, with values ranging from 25.70 to 52.03%. The economical analysis proved the eucalyptus treatment to have the best partial net return, as well a???? ?s the lowest variable partial cost. Having reached similar results to those obtained with the chemical control, the use of plant extracts can be considered as a management alternative within plague control programs.
Palavras-chave : damage percent; economical analysis; yield; insecticides.