由Neopestalotiopsis rosae引起之臺灣草莓新病害與藥劑篩選

Studies of a new disease on strawberry caused by Neopestalotiopsis rosae in Taiwan

2019年12月至2020年2月間，於苗栗大湖草莓園及南投正瀚生技公司溫室觀察到草莓葉片有紅褐色至深棕色病斑，病徵類似炭疽病，另果實亦有紫色、褐色或白色水浸狀病徵，後期有白色菌絲產生。同時亦自屏東縣林邊鄉採集紫色水浸狀病徵的蓮霧果腐病果實。兩個作物之病葉、病果經分離、純化後，進行菌落與孢子形態觀察，並進行接種試驗。此外透過增幅internal transcribed spacer、β-tubulin基因和transcription elongation factor基因之序列進行分子鑑定。初步結果認為引起草莓病害之病原菌為Neopestalotiopsis rosae，由其危害病徵定名為草莓葉斑病。蓮霧果腐病原菌為Neopestalotiopsis sp.。Neopestalotiopsis已於中國、西班牙及巴西等國家被報導可感染草莓葉片、果實、冠部及根部，而在台灣草莓為首次鑑定命名。本研究欲了解不同品種的草莓對N. rosae及蓮霧果腐病原菌之罹病程度，三個品種的草莓以離體葉片接種測試，結果顯示香水為感病品種，桃薰為中感品種，豐香不易被感染屬抗病品種。N. rosae於104 conidia/ml濃度時即可感染香水葉片，而蓮霧果腐病原菌在104及105 conidia/ml接種濃度下，皆不易感染前述草莓品種之葉片，但當接種濃度提高至106 conidia/ml時，三個品種的草莓葉片均會出現病徵，顯示蓮霧果腐病原菌對草莓葉片感染性較差，且罹病程度仍以香水最為嚴重。果實接種結果顯示與葉片接種結果一致。近幾年因豐香對炭疽病較感病而不易栽培，農民開始改種香水，可能就是造成N. rosae在這兩年感染較嚴重的原因。進一步以培養基添加藥劑測定抑制N. rosae菌絲生長的效果，結果顯示25%撲克拉乳劑、25.9%得克利水基乳劑、75g/L依普座乳劑、39.5%扶吉胺水懸劑、80%鋅錳乃浦可濕性粉劑及62.5%賽普護汰寧水分散性粒劑有較佳的抑制效果，抑制率均可達90%以上，僅62.5%賽普護汰寧水分散粒劑在植物保護資訊系統推薦使用於草莓灰黴病防治。

"During Dec. 2019 to Feb. 2020, the leaves of strawberry with red brown to dark brown lesions, the symptom looked like anthracnose. The fruits of strawberry with purple, brown, white and water-soaked symptoms, at later stage, it will appear white mycelium. The infected leaves and fruits of strawberry were collected from Dahu strawberry farm, Miaoli county, and the green house in CH Biotech R & D Co., Nantou city, LTD. At the same time, the fruits of wax apple with purple and water-soaked symptoms were collected from Linbian township, Pingtung county. The pathogens of leaves and fruits of strawberry and wax apple were isolated, purified and colonized to observe the spores, and inoculation. The pathogens of strawberry (SL) and wax apple (WF) were identified as Neopestalotiopsis rosae and Neopestalotiopsis sp., respectively, based on the combined sequences of internal transcribed spacer, β-tubulin and transcription elongation factor. Neopestalotiopsis were reported infecting the strawberry leaf, fruit, crown and root in China, Spanish and Brazil, however N. rosae was identified in Taiwan for the first time. In this study, N. rosae and the pathogen of wax apple fruit rot were inoculated on detached leaves of three different strawberry varieties. The result showed 'Aroma' was susceptible, 'Tokun' was moderate resistant, and 'Taoyuan No.1' was resistant. N. rosae. could infect the leaf of 'Aroma' by inoculated the concentration of 104 conidia/ml. The pathogen of wax apple fruit rot could not infect three different strawberry varieties with the concentration of 104 and 105 conidia/ml. If the inoculated concentration increased to 106conidia/ml, the pathogen of wax apple could infect three different strawberry varieties. It showed that pathogen of wax apple could not infect the leaf of strawberry easily, and 'Aroma' is the most susceptible variety. The farmers change the cultivated varieties into 'aroma'. It may cause N. rosae. damaged more intense. Moreover, growth inhibition rate of fungicides were tested. The result showed that 25% prochloraz EC, 25.9% folicur EW, 75 g/L epoxiconazole EC, 39.5% fluazinam SC, 80% mancozeb WP, and 62.5% cyprodinil + fludioxonil WG had better suppression effect, and the growth inhibition rate could reach up to 90%. Only 62.5% cyprodinil + fludioxonil WG was recommended to control the strawberry Botrytis disease in Plant Protection Information System."