Preparation of distribution and severity map for Dubas bug (Ommatissus lybicus) in Bam region by Geographic Information System

The GIS is a computer system for storing, processing and displaying land reference data that is used to assist in decision making in specific crop management. In this study, the technology of GIS has been used as a quick and easy solution in monitoring Dubas bug (Ommatissus lybicus de Bergevin). The aim of this research was to prepare a digital map of distribution and density of pest, to determine the outbreak points and the direction of contamination spreading and determining the areas of orchards infested by the pest in Bam and Browat. For this purpose, orchards of the Bam and Browat area were networked using Google Earth, then from each cell, an orchard, and in total in 41 orchards, the density of pest was measured using pest and honeydew counts. Then, the data were entered into the GIS so that the distribution maps and pest density were developed and evaluated. The results showed that in most orchards where pest density was measured, the damage was moderate to high. In more than 69% of the orchards, the density of Dubas bug (O. lybicus) was moderate, high and very high. For this reason, it can be said that more than 69% of the orchards in the area need immediate attention. These orchards should also be reconsidered for redesigning and improving practices such as reducing tree density, pruning and fighting pests. The severity of pest infestation in the northeastern and southeastern boundaries and generally in the east and south of the region is much higher than the northwest of the area. Therefore, the control practices should be focused on regions ranging from 58 degrees and 22 minutes east longitude and 29 degrees 7 minutes northern latitude to 58 degrees and 29 minutes east longitude and 29 degrees 2 minutes northern latitude. The elevation map showed that in a distance of 21.5 km there was altitude differences between regions, the altitude increased from 975 m in south of Brovat to 1190 m in north of Bam. From south of Browat area to the north of Bam, the severity of pest density has decreased. From the results, this level of information can be ascertained that as the altitude increased, the severity of the pest decreased. The total area of the date palm orchards of Bam and Brovat was estimated 3647 hectares calculated with the help of satellite image of Sentinel 2 and controlled by the classified classification. The area of gardens where the average pest density was moderate to very high was 2533 hectares.