臺南場轄區為洋香瓜主要的栽培區之一，2008年底至2009年初臺南市洋香瓜栽培區，罹患南瓜捲葉病毒(Squash leaf curl virus, SqLCV)情形相當嚴重，造成嚴重經濟損失。南瓜捲葉病毒屬雙生病毒科（Geminivirdae）的Begomovirus 屬，此病毒由銀葉粉蝨（Bemisia tabaci species complex）所傳播，屬持續循環型（ persistent-circulative ） 的病毒。於2009年至2011年採集洋香瓜栽培區疑似罹病毒之捲葉葉片及銀葉粉蝨活蟲，抽取其DNA，並以滾環擴增法(Rolling Circle Amplification, RCA)檢測帶毒率及罹病毒率，共計採樣雲嘉南21個鄉鎮189個洋香瓜栽培區的1873個銀葉粉蝨樣品，檢測單一園區之銀葉粉蝨帶毒率自0％~100％均有，平均帶毒率28.6％。並選定10個不同洋香瓜栽培園區調查銀葉粉蝨帶毒率與洋香瓜罹患南瓜捲葉病毒之關係，結果顯示洋香瓜生育初期銀葉粉蝨密度高，又有帶毒，約2週罹病毒率即可高達5成左右，但是生育中後期，即使是銀葉粉蝨密度高而且百分之百帶毒，調查區域內並無植株感染捲葉病毒，所以種植初期針對媒介昆蟲銀葉粉蝨的防治非常重要。
The Percentage of Viruliferous Whitefly affected the Squash Leaf Curl Virus Disease Occurred at Different Growth Stages of the Muskmelon Plants
Ｐeng, J. C. and H. Y. Tsai
Cucurbits are one of main economic crops at Tainan area. In late 2008-early 2009, muskmelon plantings were seriously damaged by Squash leaf curl virus (SqLCV, Genus Begomovirus , Family Geminiviridae) infection, resulting in great loss in Tainan County. SqLCV transmitted by whiteflies (Bemisia tabaci species complex), is persistent-circulative viral pathogens in cucurbits. This survey was conducted during 2009 to 2011. Samples from muskmelon (Cucumis melo L.) plants with systemic leaf-curl symptoms of virus-like infection and whiteflies were collected from the cultivated areas in Tainan area. The rolling circle amplification (RCA) method was used to detect the circular DNA genome of SqLCV and applied in the survey of SqLCV in whiteflies and cucurbit crops. There were 1873 whitefly samples were collected from cucurbits field in Yunlin, Chiayi and Tainan County. From 0% to 100% whitefly samples were found in the percentage of viruliferous. The average percentage of viruliferous is 28.6%. Ten muskmelon fields were selected to study relationship between the percentage of viruliferous whitefly and the Squash leaf curl virus disease occurred on muskmelon plants. The result showed that if the plants in early growth stage had high population of viruliferous whitefly, 50% of muskmelon plants would infected SqLCV. But on the medium-late growth stage, even with high whitefly population density, containing high percentage of viruliferous members, no muskmelon plants were infected. Therefore it is important to control the whitefly population on early growth stage of the muskmelon plants.
Key word: Squash leaf curl virus ( SqLCV); Whitefly
; Rolling circle amplification（RCA）
Accepted for publication: September 13 , 2012