In this study, three apple orchards in Chungnam were selected to review pesticide sprayings conditions, pesticide deposit amounts, and pest control effects while spraying different spray water volumes by the customary methods. In the first orchard, the spray water volume of acetamiprid 8% WP targeting moths used in 2014 was 372 L/10 a and the one used in 2015 was 302 L/10 a, i.e. by about 70 L smaller as compared to the previous year; however, no difference in the control value was observed. Meanwhile, for control of A citricola,, acetamiprid 2.5% wettable powder was used; the spray water volume used in 2014 was 453 L/10 a and the one used in 2015 was 378 L/10 a, i.e. by about 70 L smaller as compared to the previous year. The well-sprayed sections showed pest control effects not lower than 95%, while the poorly sprayed sections showed pest control effects of about 78%. In the second and third orchards, .the control target pest was G. molesta and the spraying pesticide used was acetamiprid 8% WP. The spray water volumes used in the second and third orchards were about 349 L and 378 L, respectively, and there was no problem in the control values. For control of A citricola, imidacloprid 10% wettable powder and flonicamid 10% water-dispersible granules were used as spraying pesticides. The spray water volumes of these two pesticides were 355 L and 380 L per 10 a, respectively, i.e. smaller than the reference volumes; however, no problem in the overall pest control was observed. Therefore, our results suggest that pesticide deposit amounts on water-sensitive papers are proportional to increases in the dose; however, the dose exceeding the appropriate concentration is not related to the deposit amounts.
