"Three spray treatment" technology for annual pest control in pear orchards of northern China
Chemical pesticides seriously affect the ecological environment and fruit safety. Currently about ten pesticide sprayings are done every year in most pear orchards for pest and disease control in northern China. Based on more than ten years of our investigation data on main pear pest and disease occurrence characteristics, three spray treatment (TST) technology and techniques were figured out, combined with the roles of natural enemies and the techniques of paper bag cover on pear fruits after fruit bearing and corrugated paper tied on tree trunks or main branches. Phenological period defined each spray time. The TST technique is the following: first spray: pear flower bud finished dormant phase and just started bud break phase to control the population of Cacopsylla chinensis, Grapholitha molesta, Tetranychus urticae, Cladosporium cucumerinum, Phyllactinia pyri and Physalospora piricola, even though some insect pests and pathogens had not or had just finished their hibernation. Second spray: petal fall about 80-90%, most insect pests were in the phase of a post-hibernation for control of C. chinensis, G. molesta, T. urticae, Panonychus ulmi, Aphanostigma jakusuiense, Janus piri, Hoplocampa pyricola, C. cucumerinum, P. pyri and P. piricola, Gymnosporangium haraeanum during this period. Third spray: just before paper bags are put to cover pear fruits (thumb finger size). In late September, the corrugated paper began to be tied after the rainy season, then collected and burned in the middle of next January. The main pest objects were C. chinensis, G. molesta, P. ulmi, Pseudococcus comstocki, Schizaphis piricola, C. cucumerinum, P. pyri, P. piricola, G. haraeanum. The pest and disease population were controlled down to economic threshold level with less use of pesticides than with the conventional EST.
Liu, Q.Z., Rong, R., Wang, J., Zhao, X.M. and Bai, P.H. (2021). "Three spray treatment" technology for annual pest control in pear orchards of northern China. Acta Hortic. 1303, 381-388
chemical pesticide, pear orchards, pest control, spray time reduction