Reducing Fungicidal Spray Frequency for Major Apple Diseases by Increasing the Spray Interval from 15 to 25 days
2009
Lee, D.H. (Apple Experiment Station, National Horticultural Research Institute, RDA, Gunwi, Republic of Korea) | Shin, H.C. (Central Research Institute, Kyung Nong Co. Ltd., Gyeongju, Republic of Korea) | Cho, R.H. (AgroLife Research Institute, Daejeon, Republic of Korea) | Uhm, J.Y. (Kyungpook National University, Daegu, Republic of Korea), E-mail: jyuhm@knu.ac.kr
During the course of a study to develop a spraying program at 15-day spray intervals, two important findings were identified allowing for further reduction of spray frequency by increasing the spray interval. In evaluating the contribution of fungicides from a 15-day spray interval program, control of white rot, which is of prime importance in Korea, was not affected, in spite of the extended spray interval caused by omitting the fungicides during the season. In another experiment assessing the duration of the protective activities of several key fungicides used in the 15-day spray interval program, infection control was maintained for almost 30 days for some fungicide. Based on these two findings, a basic spraying program with a 25-day spray interval was developed. This program was modified for four successive years to improve the control efficacy against bitter rot and Marssonina blotch, which sometimes causes as much damage as white rot.
显示更多 [+] 显示较少 [-]