Preliminary Screening of Control Agents and Exploration of Optimum Fire Blight Control Period in Korla

【Objective】 In this experiment, the aim is to screen out chemical agents and suitable period for controlling fire blight in the hope of providing a basis for the prevention and control of the disease. 【Method】 The field efficacy trials of 14 kinds of commercial fungicides were carried out, the chemical control agents were screened by conventional spray, and the best prevention and treatment period was given in different periods, and the targeted smear method was used to treat the severely diseased parts. 【Result】 The control effects of copper preparations were better than agricultural antibiotics. The control effects of copper hydroxide, thiamethoxam copper and copper abietate were 96.2%, 68.5% and 66.7%, respectively. The efficiency at the early flowering stage was significantly better than that at the full flowering stage and fruit enlargement stage, the control effect of copper preparation was higher than that of other agents, and the efficiency of copper hydroxide at the early flowering stage was 96.2%.For the onset pear branches, the expansion of lesions were effectively inhibited by applying the plant heterogenous polyphenols, and inhibition ratio reached 92.1%. 【Conclusion】 Copper preparations could be sprayed at the early flowering stage to resist pathogen invasion. Non-copper preparations can be used to prevent and cure this disease in flowering period, avoiding drug damage, during the fruit enlargement period, plant miscellaneous polyphenols or thiamphenone can be used for directional application.