SPATIAL DISTRIBUTION OF POSTURES AND NYPHS OF Quesada gigas (HEMIPTERA: CICADIDAE) IN THE COFFEE CULTURE

Abstract

The objective of this work was to determine the spatial distribution of postures and nymphs of Quesada gigas in coffee plots with a history of infestation (Mundo Novo, Icatu 2939 and Icatu 2944), aged thirty, seventeen and fifteen years, respectively. The spacing between the plants was 4.0 x 1.0 m between rows and in the row respectively, totaling 10,000 m2 in each plot. The plots were divided into 100 plots of 10 x 10 m, and one plant per plot was marked using GPS. Three dry branches from the upper third of the marked plant measuring approximately 20 cm were collected fortnightly, totaling 300 branches per plot, from October to December 2014 and October and November 2015. For the evaluation, they were placed in a paper bag and taken to the UNESP/FCAV Plant Health Department. The study of nymphs was carried out by opening trenches made in December 2015, with dimensions of 0.50 x 0.50 x 0.50 m. From the base of the trunk, the collected nymphs were placed in glass containers with a 70% alcohol solution for subsequent counting. The identification of nymphal instars was performed with the aid of a stereoscope. Data were analyzed using dispersion indices using Excel® and geostatistical analysis using ArcGIS 9.3 and Surfer 7.0 software for Windows. Thus, it can be concluded that the calculated indices were aggregated in the field and the use of geostatistics allowed mapping the distribution of Q. gigas.