Occurrence Tendency and Decrease of Fruits Brix According to Increasing Grapevine Leaf Spot Disease Caused by <i>Pseudocercospora vitis</i>

Research in Plant Disease 2004;10(4):341-344.
Published online December 31, 2004.

포도나무 갈색무늬병의 최근 발생 동향과 다발생에 의한 과실의 당도저하

박종한^*, 한경숙, 이중섭, 서상태, 장한익, 김흥태¹

원예연구소 원예환경과, ¹충북대학교 식물의학과

Occurrence Tendency and Decrease of Fruits Brix According to Increasing Grapevine Leaf Spot Disease Caused by Pseudocercospora vitis

Jong-Han Park*, Kyung-Sook Han, Jung-Sup Lee, Sang-Tae Seo, Han-Ik Jang, Heung-Tae Kim1

Horticultural Environment Division, National Horticultural Research Institute, Suwon 441-440, Korea
¹Plant Medicine Division, Chungbuk Natl. Univ., Cheongju 361-763, Korea

Correspondence: Jong-Han Park,Phone)+82-31-290-6231, Fax)+82-31-290-6259, E-mail)pjhn@rda.go.kr

Received: November 09, 2004

Abstract

Grapevine leaf spot caused by Pseudocercospora vitis also called leaf Isariopsis spot which is one of the most important disease in Korea. Spots on the leaves are irregular to angular. They are brown, measure 2~20 mm in diameter. Campbell Early, the major grape cultivar in Korea, is very susceptible to this disease. Leaf spot of grape is outbreak about 95% in ratio of diseased leaves according to the areas and management state of orchards in Korea. The diseased grapevines have some difficulty in raise of the trees by early defoliation and decrease the quality of fruits by disadvantage of assimilation products accumulation. Severe outbreak of the grapevine leaf spot is one of the factors that decrease of sugar content of the fruits about 20%. The strong negative correlation was observed between disease increase of grapevine and decrease of sugar content of the fruits. The correlation equation between relative sugar content of fruits and accumulated percentage of diseased leaves was Y = 0.0009X² - 0.3717X + 116.45(r²= 0.98).

Key Words: Grapevine, Leaf spot, Pseudocercospora vitis, Sugar content