Abstract

FABERI, A.J; CLEMENTE, N.L; MANETTI, P.L  and  LOPEZ, A.N. Nivel de daño económico de Armadillidium vulgare (Latreille, 1804) (Crustacea: Isopoda) en el cultivo de girasol. RIA. Rev. investig. agropecu. [online]. 2014, vol.40, n.2, pp.182-188. ISSN 1669-2314.

Damage function is the parameter of Economic Injury Level model (EIL). The aims were: evaluate the injury of Armadillidium vulgare in the sunflower crop and determine the damage function in the crop for estimating EIL. The study was done in three agricultural cycles. Assessments were conducted in three agricultural cycles according randomized complete blocks design with five replicates. Eight sunflower seeds were sown and were infested with: 0 (control), 20, 40, 60, 80 y 120 individuals m^-2 of A. vulgare in 1 m² plot. Injury on hypocotil and cotiledons, number of plants per square meter and yield were evaluated. Damage functions were calculated (A. vulgare density and yield loss proportion regression). Differences in the proportion of plants with severe injury were observed among A. vulgare densities. This category of injury was correlated with A. vulgare density, with the number of plant per square meter and with yield. Damage functions represented a proportion of yield loss of 0.0033 (R²= 0.64), 0.0023 (R²= 0.49) and 0.0048 (R²= 0.71) for A. vulgare individual by square meter in three agricultural cycles. When all data were combined this was 0.0035 (R²= 0.59). Considering mean market values, the EIL of A. vulgare in sunflower crop ranged from 22 to 81 individuals m^-2. Taking into account the determination coefficients and that A. vulgare has variable eating habits the 0.0033 damage function is recommended to determine EIL of A. vulgare in sunflower crop.

Keywords : Damage function; No tillage; Integrated Pest Management; Pill bugs.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )