Floating population of diaphorina citri in different varieties of sweet orange (Citrus sinensis) produced in commercial orchard

Brazil is one of the largest citrus producers in the world and also the largest exporter of orange juice. At present, Huanglogbing is the main disease of citriculture, due to its rapid spreading and provoked damages. The spread of the disease occurs through the psyllid Diaphorina citri. The main objective of monitoring population fluctuation is to detect or determine prematurely the incidence of the pest. The objective of this study was to evaluate the population fluctuation of the psyllid in commercial sweet orange orchard (Citrus sinensis) containing different citrus varieties in the state of Paraná. The evaluated varieties were: Valencia, Pera Rio, Folha Murcha, Rubi and Ponkan grafted on Rangpur lime (Citrus limonia), and with an average spacing of 6.5m between row and 3.0m between plants, totaling an area of 14.24 ha. With the aid of a magnifying glass the insects were identified and counted in each of the traps. The insects presented different behavior in the different varieties in relation to the traps. In the Valencia variety there was a higher average capture of psyllids (4.11) compared to the other varieties. In all varieties, larger adult psyllid catches were noted on the outskirts of the plots when compared to the traps positioned inside the plots. The altitude, temperature, relative humidity (RH) of the air and precipitations, vegetative flows are factors that can influence the occurrence, development and capture of D. citri.