Abstract

BADO, Silvina. Estimación de la función de daño potencial y nivel de daño económico de Caliroa cerasi L. (Hymenoptera: tenthredinidae) en el Valle Inferior del Río Chubut (región Patagonia sur, Argentina). RIA. Rev. investig. agropecu. [online]. 2019, vol.45, n.2, pp.279-284. ISSN 1669-2314.

Caliroa cerasi L. (Hymenoptera: Tenthredinidae), popularly known as “pear slug”, is the main pest of cultivated cherry in the Southern Patagonia Region. The larvae cause significant indirect damage by feeding on the foliage. The first generation of the insect coincides with the period of development and maturation of the fruits. Insect management is based mainly on chemical control in moments close to harvest. However, quantitative criteria for decision making, which would help to rationalize insecticide applications, have not been developed. This situation could contribute to ecotoxicological problems and unnecessary expenses for the grower. The objective of this work was to establish a potential crop damage function (loss of yield (PR) as a function of larval density) for “pear slug” from laboratory data, and to calculate the economic damage level for the most used pyrethroid (lambdacilotrina). The methodology consisted in determining the leaf area consumed by individual larvae bred in the laboratory and trees potential yields (kg tree-1) considering the linear relationship between photosynthetically active radiation (IPAR) and yield. The IPAR was calculated according to larval density and leaf area index (LAI). The yield function of an objective tree, with a LAI= 4, was represented by the quadratic equation PR = -1.62774x²-0,2987x + 24.55 (R² = 0.99) from which the damage function was calculated (Y = 0.1631x² + 0, 2973x - 1E-04; R² = 0.99). The economic damage level (NDE) calculated for the most frequent conditions in the valley, gave a value of 1 “pear slug” every 20 leaves.

Keywords : “pear slug”; cherry; foliar consumption; yield function; economic damage level.