Analysis of Flooding Damage by Heavy Rain on 'Fuji'/M.26 Apple Tree

집중호우에 의한 '후지'/M.26 사과나무의 침수 피해 분석

This survey was carried out to investigate the effect of flooding by heavy rain on growth characteristics and disease incidence of 'Fuji'/M.26 mature apple tree in 1998 at Kyongbuk province. The surveyed regions were Andong, Uisung, and Gunwi area. The six orchards were selected from one area, totally 18 orchards were surveyed. The flooded depth of surveyed orchards was from 70 to 350 cm, and the flooded duration was from 6 to 72 h. Defoliation ratio, number of abnormal budding, and flowering per tree were increased along with the increment of flooded depth and duration. Rooting ratio was decreased rapidly with the increment of flooded duration, and dead root ratio was 16.2% in flooded orchards. Marssonia blotch (Diplocarpon mali), white rot (Botryosphaeria dothidea) of fruit, and phytophthora fruit rot (Phytophthora cactorum) incidence were increased in flooded orchards. The analysis results of pearson correlation coefficient among surveyed items showed that higher relationship of abnormal growth characteristics and increment of disease incidence of 'Fuji'/M.26 apple trees with flooded duration than with flooded depth. With these results, the flooded depth was found to be the main factor for the abnormal growth characteristics and disease incidences of 'Fuji'/M.26 apple trees.

1998년 8월 중순 경북 북부지역에 있었던 집중호우에 의한 하천 범람으로 침수된 과수원을 군위, 의성, 안동에서 지역별 6개 과수원씩, 총 18개 과수원을 대상으로 '후지' 사과나무의 생육 상황과 주요 병해 이병률을 조사하였다. 조사 과수원의 침수 깊이는 70cm-350cm였고, 침수 기간은 6시간-72시간이었다. 침수 피해 사과원의 낙엽률, 발아율 및 이상개화 현상은 침수 깊이가 깊을수록, 침수 기간이 길어질수록 증가하였다. 새 뿌리 발생은 침수 기간이 길어질수록 급격히 감소하였고, 침수로 인한 뿌리 고사율은 16.2%로 나타났다. 잎의 갈색무늬병, 과실의 부패병, 역병 발생이 무침수 과원에 비해 크게 증가하였고, 조사 항목 간 상관분석 결과, 침수에 의한 이상 생육과 발병 증가가 침수 깊이보다는 침수 기간에 더 큰 영향을 받는 것으로 조사되었다.