Application of Climatic Factors and Orchards Disinfection for the Control of Fire Blight in Khorasan Razavy Province

Fire blight, caused by the bacterium, Erwinia amylovora, is a serious disease of pome fruits in many regions of the world and Iran. Several models based on climatic and phonological data were developed to prevent fire blight during bloom, thus improving our ability to control this phase of the disease by the timely application of antibiotics sprays in orchard. In this study (i) the causal agent of fire blight were detriminated in infected orchards (ii) removal infected plant tissues (iii) air temperature, and relative humidity were recorded (iiii) spraying and application of treatments were performed to prevent the blossom blight and based on claimatic condition, phonological trees and Thomson model. Experiment was performed as Random Complete Blocks Design (RCBD) with three replications. Results showed minimum effects in streptomycin 100ppm treatment (6.22%- 8.5%) on preventing of infection, especially when applied three bloom sprays during sensitive stages of flowering at 150C-18.10C. Then oxytetracycline 200ppm and starner 300ppm were ranked next respectively (8.533%-16.33%). The effective hess of copper oxycloride 1/1000 is depending on relative humidity and rain. Results that indicated interaction among bloom period, time of flowering and temperature could reduce number of spraying compared to Thomson model. Therefore we can use this technique in orchards of Golmakan, Chenaran, Nyshabour, Mashhad and other geographic areas where pome fruits are grown and have similar climatic condition.