Liu, T. Y., Chen, C. H., Wang, L. J., Hung, T. H., Hsu, M. H., and Wu, M. L. 2021. Investigation of Camellia tree diseases in Taiwan and establishment of a rapid detection method for Colletotrichum spp.. Taiwan Journal of Forestry Science 36(1):1-19.  https://doi.org/10.7075/TJFS

          油茶為臺灣早期的造林樹種，也是近年重要油料作物。油茶地上部病害為造成油茶產量與品質下降的主要原因之一，但卻缺少相關之研究。本研究經由臺灣北部及中部油茶園的病害調查，發現在北部油茶園葉部病害以餅病、葉斑病和軟腐病為主，中部則以葉斑病和炭疽病最為常見。進一步將感病油茶葉片進行組織分離，獲得真菌分離菌株，並依菌落型態進行分群後，從中選取15株真菌分離株，萃取核酸並定序與序列比對，發現油茶葉片及果實的植物病原真菌，以炭疽病菌屬(Colletotrichum spp.)真菌所占比例最高。此外，自油茶罹病葉上分離而得的菌株還包含Alternaria sp.、Botryosphaeria dothidea、Botryotinia fuckeliana (Botrytis cinerea)、Lasiodiplodia pseudotheobromae、Neofusicoccum parvum、Pestalotiopsis sp.、Phomopsis sp.、Sclerotinia sclerotiorum。這些真菌分離株皆有被報導為植物病原菌，但在油茶上的研究仍相當缺乏。進一步將真菌分離株的ITS序列進行親緣關係分析，可以發現感染油茶的炭疽病菌，主要來自於C. gloeosporioides和C. acutatum這兩個種群，並與自其他作物上分離到的常見炭疽病菌歸為同一系群，與其他葉部潛在病原真菌在類緣關係上有所區別。有鑑於炭疽病菌的兩個種群為油茶主要病原菌，本研究首次針對油茶上此兩個重要炭疽病菌種群發展快速檢測方式。透過真菌核酸ITS區域，設計3組油茶炭疽病菌之專一性引子對，利用分子檢測技術(聚合酶鏈鎖反應，PCR)來進行快速檢測。結果顯示本研究設計之引子對油茶炭疽病菌具良好專一性及靈敏度，並可成功區分在油茶上主要造成炭疽病菌的不同種群。透過快速檢測方式的建立，未來將有助於病原菌在潛伏感染時期的檢測。本研究自臺灣油茶罹病葉片上分離出炭疽病菌屬及其他8種真菌，有助於了解油茶葉部之潛在病原菌，同時針對危害嚴重之油茶炭疽病發展快速檢測技術，可作為未來油茶病害防治與健康管理之用，提供病害早期發現早期防治的管理模式。

 

寧方俞、呂柏寬。 2021。 茶輪紋葉枯病之發生及其病原菌特性與品種致病性分析。植物醫學 63 (1) : 3 - 8。 https://doi.org/10.6716/JPM.202103_63(1).0002

          2018年2月接獲新北市文山茶區臺茶12號茶樹發生葉部病害，病斑圓形並常具有輪紋，經由田間病徵、病兆、菌株形態及分子檢測比對，確認為 Haradamyces foliicola 在茶樹上造成之輪紋葉枯病。病原菌於常溫保存於PDA斜面或無菌水，於一個月後活化菌絲容易變異，生長不佳；可以茶葉浸出液培養基(TIA)培養生長，但生長速度不如PDA及稻稈浸出液培養基(HAY)。於品種致病性檢定試驗中，確認以病菌繁殖體可感染臺茶12號、臺茶13號、臺茶17號、臺茶18號、臺茶19號、臺茶20號、四季春、青心大冇共8個測試品種，惟青心烏龍未產生發病情形。

 

曾敏南。2021。 蓮霧黃腐病之病原真菌鑑定。植物醫學63 (2): 17 - 22。

            高雄市六龜區及屏東縣林邊鄉、南州鄉及東港鎮等地栽培之蓮霧(Syzygium samarangense (Blume) Merr. & Perry)曾經因蓮霧黃腐病危害，而造成重要的經濟損失。蓮霧黃腐病是受真菌病原感染，受害初期，果實形成水浸狀斑，斑點隨後快速擴大、褪色、褐化並產生白色菌絲。分離自屏東縣林邊鄉的蓮霧黃腐病菌，經回接及再分離確認為蓮霧病原真菌。此外，造成蓮霧黃腐病的真菌亦可感染大豆(Glycine max)、花生(Arachis hypogaea)及紅豆(Vigna angularis)葉片，並可能感染茄子(Solanum melongena)、檬果(Mangifera indica)及棗(Ziziphus mauritiana)。以內轉錄間隔區(internal transcribed spacer, ITS)、組蛋白H3基因(histone H3)、β微管蛋白基因(β-tubulin)及轉錄因子-1α基因 (transcription factor-1α, TEF-1α)部分序列進行多基因類緣分析，以及形態觀察比對結果，判定造成蓮霧黃腐病之病原真菌為Calonectria sulawesiensis。

 

袁琴雅、蘇俊峯、黃晉興。2021。由Phytopythium helicoides引起之玫瑰根腐病。植物醫學 63 (3): 1 - 8。 https://doi.org/10.6716/JPM.202109_63(3).0001

        2015年在南投縣埔里鎮數處玫瑰栽培田及國姓鄉一處玫瑰育苗場發現一種玫瑰新病害，主要病徵為植株幼苗根腐與莖基部褐化腐敗，嚴重時會造成植株萎凋枯死。一種腐霉菌由罹病植株的根部與莖基部組織可持續的被分離得到，於26－35℃之溫室條件下，將該腐霉菌的游走子懸浮液接種到盆栽玫瑰幼苗根部，2週之後會出現與田間及育苗場罹病玫瑰苗相同的病徵，並能再分離得到與原接種的同種腐黴菌，完成科霍氏法則測試，證實其病原性，並將此病害定名為玫瑰根腐病。此病原菌經由形態特徵以及核醣體內轉錄區間（rDNA internal transcribed spacer）核酸序列之鄰近連接法（Neighbor-Joining）分析，鑑定為Phytopythium helicoides。此病原菌在瓊脂培養基上菌絲生長溫度範圍為12－40℃，最適生長溫度為28－36℃，經由人工接種証實本病原菌可感染數種供試作物幼苗，可在玫瑰、巴西野牡丹、藍星花、草莓及左手香造成嚴重根腐病徵，在青椒及萵苣造成輕微根腐，可以感染百香果、胡瓜及青蔥根部但不會造成病徵。

 

梁鈺平、吳昭蓉、 蔡惠文、倪蕙芳。2021。Lasiodiplodia theobromae及Lasiodiplodia pseudotheobromae在台灣引起之酪梨枝條潰瘍病。台灣農業研究70 (2): 81–97。

          酪梨枝條潰瘍病於國外許多酪梨栽培國家均曾報導，主要由多種葡萄座腔菌科（Botryosphaeriaceae）之真菌感染引起。本病亦廣泛發生於台灣主要酪梨栽培地區，然病原菌至今尚不明確。本研究自台灣各地共7個酪梨園具潰瘍病病徵之枝條組織進行病原菌分離，共收集到13個菌株，透過型態鑑定及核糖體內轉錄區間（internal transcribed spacer; ITS）和轉譯延長因子1-α（translation elongation factor 1-α gene; TEF-1α）之序列進行類緣分析，結果顯示此些菌株均屬於Lasiodiplodia theobromae或Lasiodiplodia pseudotheobromae。此兩菌株之菌絲最適生長溫度均為約30℃；對酪梨枝條及果實均具病原性，可於枝條接種處造成白色粉末分泌及內部組織褐化，於果實上亦會造成黑色軟腐病斑。本研究為首篇描述台灣酪梨枝條潰瘍病及其相關病原菌之報告，研究結果顯示台灣之病原菌種類與大部分國外酪梨栽培地區造成酪梨枝條潰瘍病之主要病原菌不同。本研究將可提供未來進行酪梨枝條潰瘍病之流行病學，以及建立其有效之病害管理策略研究時之重要參考資訊。

 

        羅勒枝枯病（basil dieback）為羅勒栽培時期的真菌病害之一，於屏東縣萬丹鄉發現羅勒植株的枝條於採收後，從枝條傷口處開始乾枯，呈現黑褐色壞疽狀病徵，逐漸蔓延至全株、死亡。從不同羅勒栽培區，相同病徵的罹病組織中分離出同一種真菌。室溫下，於馬鈴薯葡萄糖瓊脂（potato dextrose agar; PDA）培養10 d後，呈現邊緣為白色至淺灰色，中央為深橄欖綠色的菌落。根據此病原菌之型態特徵，與核醣體核酸基因（rDNA）的內轉錄區（internal transcribed spacer; ITS）序列鑑定結果，將該病原菌鑑定為Corynespora cassiicola，並以柯霍氏法則證明，此真菌為造成羅勒枝枯病之病原菌。菌絲生長溫度範圍為15－35℃，孢子發芽溫度範圍為10－35℃。在25℃下，維持連續48 h高濕度環境中，羅勒枝枯病之罹病率可達75%，為此病害最適發病條件。評估植物保護資訊系統中，羅勒葉斑病（Alternaria alternata引起）之推薦用藥，四氯異苯腈、保粒黴素（甲）、依普同與克收欣，於濃度1、10與100 ppm，對羅勒枝枯病菌菌株CC-2、CC-3在PDA上菌絲生長之影響。結果發現，依普同對CC-2與CC-3均有最佳的菌絲生長抑制率，分別為64.4－77.0%與65.0－75.4%；克收欣次之，分別為60.7－66.8%與58.8－63.6%，而四氯異苯腈與保粒黴素（甲）則介於40－50%。故依羅勒葉斑病（A. alternata, leaf spot）推薦藥劑之稀釋倍數使用，可同時防治羅勒枝枯病發生。

 

傅于珊、丁昭伶、孫韻晴、黃健瑞。2021。首次報導由Phytopythium  helicoides造成的芋軟腐病。中華民國植物病理學會109年度年會論文摘要。植物醫學 63 (4): 42。 https://doi.org/10.6716/JPM.202112_63(4).0005

          芋 (Colocasia esculenta) 為天南星科 (Araceae) 芋屬植物，為國內重要雜糧作物之一，其地下球莖為主要的食用部位。芋球莖軟腐病常導致芋生產上的嚴重經濟損失，芋軟腐病研究團隊先前已確認芋球莖軟腐病包含 Fusarium solani 造成的芋球莖真菌性軟腐及軟腐細菌造成的細菌性軟腐病。此外，在 2018 至 2020 年間於苗栗及高雄地區採集具有褐色凹陷且邊緣呈現水浸狀病徵的芋頭球莖樣本，並取其病健部組織進行分離，純化後得到數個分離株，除 F. solani 外，亦陸續分離到菌落形態與卵菌相似的菌株，其在馬鈴薯葡萄瓊脂培養基 (PDA)上培養，菌株生長快速且為白色菌落，富有氣生菌絲，菌絲透明；將菌絲塊接種在芋切片上，可造成水浸狀、軟腐病徵，初步確認其病原性。挑選 2 菌株利用 ITS (Internal Transcribed Spacer)、COX I (Cytochrome c oxidase subunit I) 基因片段序列進行分子鑑定，所增幅出之序列以 NCBI blastn 進行比對，與 GenBank 中 Phytopythium helicoides FL231 菌株 (GenBank accession no. KY084741.1) ITS 序列有 98.27－99.38% 以上的相似度，與 P. helicoides GDGJ6 菌株 (GenBank accession no. KT750956.1) COX I 序列有 98.22－99.12% 的相同度，確認所得分離株為 P. helicoides。另在 25 °C 及 37 °C 下以 Corn Meal Agar (CMA) 培養，觀察兩分離株之生長情況，兩者皆可在此兩溫度下生長，且在 37 °C 下生長速率高於 25 °C，並具有顯著差異，顯現出 P. helicoides 其耐高溫之特性。為確認其致病性，後進行芋球莖接種，將菌絲塊接種於人工傷口處，7 天後切開芋球莖，可於處理組之接種處觀察到水浸狀、褐色病徵，與田間所觀察到的病徵相符，並可再次分離到 P. helicoides；對照組則無病徵出現，也未分離到 P. helicoides，完成柯霍式法則，此為在臺灣證實 P. helicoides 可造成芋軟腐病的首次報導。

(嘉義大學; 苗栗區農改場)

 

陳錦桐、褚哲維、林玫珠、吳容儀、戴廷恩。2021。由 Sclerotinia  sclerotiorum引起之麥桿菊莖腐病。中華民國植物病理學會109年度年會論文摘要。植物醫學 63 (4): 42 - 43。 https://doi.org/10.6716/JPM.202112_63(4).0005

        麥桿菊 (Helichrysum bracteatum) 又稱為蠟菊、不老菊，為菊科臘菊屬植物，花瓣蠟質具光澤，除植株具觀賞性之外，也是新興理想的乾燥花材料。最近在南投縣信義鄉田區發現麥稈菊植株出現枯萎症狀，且零星分布在園區，植株由莖基部開始變褐色，下位葉逐漸萎凋枯黃變色，由下逐漸往上蔓延，迅速擴展，最終導致植物枯萎，腐爛和死亡。同時在莖桿基部葉柄伴隨著白色棉質菌絲體在莖桿表面與維管束組織內生長。在莖桿上的白色的菌絲體聚集體，其發展成深色的圓形至細長的菌核。由罹病組織分離出此真菌，於馬鈴薯葡萄糖瓊脂 7 天後，為白色圓形菌落，邊緣有白熱棉絮狀發展成深褐色的圓形至細長型的菌核。將所分離的菌株，切取 7 天左右的菌絲塊，以馬鈴薯葡萄糖培養基液態培養菌絲5 天後，澆灌接種在 7-8 片本葉的麥稈菊植株，2 周後出現與田間相同的病癥，並能再分離得原接種的同種菌株，完成柯霍式法則，證實其病原性。評估此病原菌的型態特徵與 ITS (Internally Transcribed Spacer) 核酸序列鑑定結果，將此菌鑑定為 Sclerotinia sclerotiorum (Lib.) de Bary。Sawada (1919) 曾紀錄臺灣有此病菌，但至今相關研究闕如。麥稈菊莖腐病之 221 與210 菌株菌絲最適合生長溫度為 12-28℃，高 於32℃ 即停止生長，菌核形成溫度在 16-24℃，溫度與病害發生有密切關係，田間發病多在於秋冬冷涼季節，尤其發生在高濕與低於 20℃以下環境。S. sclerotiorum 寄主範圍相當廣泛，多種蔬菜、花卉均可被害，目前麥稈菊莖腐病無推薦用藥，參考植保手冊相(TARI) 關菌核病防治藥劑，在平板上試驗發現化學藥劑50% 撲滅寧可濕性粉劑、50%貝芬同可濕性粉劑、50% 快得依普同可濕性粉劑與62.5% 賽普護汰寧可濕性粉劑，這四種藥劑在抑制麥稈菊莖腐病菌菌絲生長，抑制率可達 100%。

 

林秀橤、林盈宏、Ariyawansa, Hiran A.、鍾嘉綾、洪挺軒。2021。臺灣茶赤葉枯病之病原菌菌相調。中華民國植物病理學會109年度年會論文摘要。植物醫學 63 (4): 43。 https://doi.org/10.6716/JPM.202112_63(4).0005

        茶赤葉枯病為茶樹的一種重要病害，不僅會藉由傷口感染葉片，更會直接侵染幼嫩組織，若感染了嫩芽、嫩莖等部位，會使該嫩枝條容易折斷，繼而直接造成產量損失。然而需要正確選擇防治策略之前提下，首先需釐清造成本病害之病原菌種類，又因目前國內未有針對造成本病害之調查文獻，故本研究針對造成茶赤葉枯病之病原菌種類進行調查。本研究在臺灣重要產茶地區採集似茶赤葉枯病之罹病葉片，進行病原分離、純化及利用分子生物學方法進行分類鑑定，結果顯示分別來自 8 縣市 86 處茶園樣品中，共獲得 162 株病原性真菌，其中 141 株為 Colletotrichum 屬真菌，包括 C. camelliae、C. fructicola 及 C. aenigma，其他病原菌則為 Ascomycota sp.、Fusarium oxysporum、Ceriporia lacerate、Pseudopestalotiopsis theae、Pestalotiopsis theae、Diaporthe sp.、Phomopsis sp. 及Lasiodiplodia theobromae，其中以 C. camelliae 為最主要之病原菌 (135株)。本研究確定了臺灣主要造成茶赤葉枯病之病原菌為 C. camelliae，且 C. fructicola 及 C. aenigma 為首次在臺灣茶樹上發表之病原菌。

 

蕭伊婷、歐海仁、王照仁、黃冬青、沈原民。 2021。在臺灣發現由Leveillu  lataurica引起之金蓮花白粉病及Podosphera  fusca引起之豇豆白粉病。中華民國植物病理學會109年度年會論文摘要。植物醫學 63 (4): 44。

          於 2020 年 4 月在彰化縣大村鄉，發現金蓮花葉片出現過去未曾發現的不規則黃褐色壞疽班，且大多出現在下位葉，園區發生的情形為 50-60% 左右，起初病斑為黃色暈圈，而到後期，葉片逐漸形成褐色壞疽班，嚴重者病斑會癒合，並在葉背觀察到白色粉末狀的白粉病菌構造，依據光學顯微鏡下的形態及 ITS 序列特徵，將感染金蓮花的白粉病菌鑑定為 Leveillula taurica s. str.。此外，在發現金蓮花白粉病的臨近地點亦發現甜椒葉片遭 L. taurica 感染，結果顯示此白粉病菌在本地具有一種以上的寄主植物，金蓮花與甜椒上的白粉病菌有潛力在不同寄主植物間交互感染；在同一時間點於彰化縣大村鄉田間，另觀察到豇豆葉表與葉背覆蓋白色粉狀物，到後期葉片覆滿白色粉末，使豇豆逐漸萎凋，田間的發生率為 15%-30% 左右，依白粉病菌之形態及 ITS 序列特徵將其鑑定為 Podosphera fusca，此白粉病菌在臺灣具有多種寄主植物，寄主紀錄除甜瓜、木瓜、苦瓜、紅鳳菜等作物外，本研究確認 P. fusca 能夠感染豇豆造成豇豆白粉病。

 

          草莓為苗栗地區重要觀光休閒產業，每年草莓季觀光採果遊客達百萬人次，為週邊產業帶來無限商機。目前我國草莓栽培現況，全國種植面積約 500 公頃，近 2~3 年草莓產業從原本豐香為主流品種，至 109 年 10 月於苗栗縣大湖鄉、獅潭鄉等草莓主要產區，香水品種栽植面積已高達 80% 以上，主因為豐香對炭疽病相當感病，育苗不易且產量不及香水。然而在品種汰換的同時，產業也面臨新病害的挑戰。香水品種於育苗期及產果期出現有別於炭疽病的病徵，該病害可感染葉片、葉柄、走蔓、冠部、根系及果實，在葉片上的病徵，初期為圓狀病斑，後期隨水蔓延並擴大病斑造成葉枯病徵，於潮濕環境下產生黑色環狀孢子堆。當此病害感染植株冠部造成壞疽褐化後，地上部逐漸弱化，新葉變小，葉肉顏色轉紫至紫紅色終至萎凋死亡。初步以孢子型態鑑定病原菌為 Pestalotiopsis sp.，進一步以 ITS、β-tubulin (TUB)、translation elongation factor 1-alpha (TEF) 三個基因序列進行多基因序列分析，序列 以 Multiple Alignment using Fast Fourier Transform (MAFFT) 進行比對，再以貝葉斯推斷 (Bayesian inference analyses, BI) 及最大似然 (Maximum likelihood analyses, ML) 分析，結果顯示造成臺灣草莓葉枯病之病原菌與 Neopestalotiopsis rosae 歸於同一種類。目前此病害除了在苗栗地區發現外，台北內湖、桃園新屋、新竹關西、南投清境及嘉義等區域皆有發現，田間調查發現尤以香水品種特別感病。依發生情形推測，此菌可能具潛伏感染特性，經由雨水或噴灌水彈濺傳播，並可藉由種苗帶菌至本田。因此，在防治策略上仍以健康種苗為重點，須澈底清除病葉及植株，並施用防治資材。初步從已推薦在草莓病害之藥劑於實驗室內進行感受性測試，結果顯示包含腐絕快得寧、待克利、賽普護汰寧、得克利 (於草莓炭疽病中推薦為三氟得克利)、百克敏與普克利等具有較佳抑制效果。本研究確認草莓產業面對之新病害種類，未來將篩選有效防治藥劑、非化學農藥資材及了解其流行病學，以建立綜合管理技術。

 

吳承峻、鍾文鑫、沈原民。2021。臺灣引起洋桔梗根腐與萎凋病之Fusarium屬病原鑑定。中華民國植物病理學會109年度年會論文摘要。植物醫學 63 (4): 45 - 46。 https://doi.org/10.6716/JPM.202112_63(4).0005

          洋桔梗 (Eustoma grandiflorm (Raf.) Shnn.) 為臺灣重要外銷切花。在溫室洋桔梗栽培期間常發生根腐與萎凋病徵，依台中改良場之初步鑑定可能屬於 Fusarium oxysporum，為確定引起洋桔梗根腐與萎凋之病原種類，自 2020 年 2 月開始蒐集發生根腐與萎凋病徵之洋桔梗罹病株，採集地點為彰化縣北斗鎮溫室內栽培之洋桔梗園。病害調查顯示，洋桔梗園區發生根腐與萎凋之比例約 3-5%。罹病植株發病初期僅維管束褐化，中後期受感染之莖部內呈中空或乾腐，褐化病徵延植株莖部擴展，並常於罹病組織表面出現粉狀與橘黃色分生孢子堆。有時褐化病徵亦可蔓延至葉片，造成葉部呈乾癟狀。將罹病組織攜回研究室進行病原分離與純化，結果指出所分離之菌株菌落形態相似，依 Leslie 與 Summerell 兩氏 (2006) 對 Fusarium 屬形態描述，初步鑑定所得菌株主要屬於 F. oxysporum species complex (FOSC)。進一步將單孢純化後之 FOSC 菌株以 PDA 培養，並置於 20℃光照 12 小時環境使其產生大孢子，另於 28℃ 避光環境下觀察 PDA 上之菌落特徵。培養 7 天後結果指出，菌落正面顏色為淡粉紅至紫色，氣生菌絲呈棉絮狀；背面顏色為白色淡橘色。大孢子形狀細長且略微彎曲、壁薄，長寬為 27.7- 42.8 x 3.6-4.8 μm，具 3-4 個隔膜 (少數為 2 或 5 個隔膜)；小孢子為橢圓至棒狀，長寬為 6.5-11.8 x 2.79-4.36 μm，具 0-1 個隔膜，呈假頭狀聚集於產孢細胞尖端；厚膜孢子為球狀、壁厚且平滑，單生或雙生並間生於菌絲。於病原性測試方面，以混合 0.3% 水瓊脂含 105~106 spores/ml 孢子懸浮液 15 μl，接種在拉長 2~5 個節間之洋桔梗幼苗的第一與第二節間葉腋部，結果顯示，接種 2~3 週後，出現與田間相似之病徵。另以根部浸泡方式接種 105~106 spores/ml 孢子懸浮液 10 分鐘，結果得知，在接種 2~3 週後植株出現矮化與根系腐爛的病徵，且亦可自罹病組織分離到相同形態的菌株。進一步將可引起洋桔梗病徵之Fusarium 屬菌株，萃取總DNA並增幅 TEF-1α 及 IGS 序列，經與 NCBI 資料比對與分子親緣分析，證實引起洋桔梗根腐與萎凋病之病原為 FOSC 中的 F. nirenbergiae。

 

          毛西番蓮 (Passiflora foetida) 為西番蓮科 (Passifloraceae)西番蓮屬 (Passiflora) 之二年生蔓性草本植物，又稱為小時計果或野百香果，全球熱帶地區均可見其蹤跡，常見於臺灣野外田間；文獻紀錄上為百香果木質化病毒之野生寄主。本研究於 2020 年由埔里採集到葉片出現嵌紋徵狀且果實木質化之毛西番蓮，經由間接式-酵素連結免疫吸附反應 (indirect enzymelinked immunosorbent assay, indirect ELISA)、反轉錄-聚合酶鏈鎖反應 (RT-PCR) 檢測和病毒鞘蛋白核酸定序結果，鑑定其乃屬 East Asian passiflora virus-AO 系統之病毒分離株。進一步於溫室接種試驗中，毛西番蓮之罹病組織液可成功接種於奎黎產生單斑，單斑組織回接健康的毛西番蓮以及黃百香果苗株，均能引起葉片嵌紋徵狀，確認由毛西番蓮上所分離而得之 EAPV-AO分離株 (代號 PL)，具有對原寄主以及百香果之感染力。本研究另取田間罹染 EAPV-AO 之毛西番蓮木質化果實之種子，播種後之實生苗均未檢出病毒，顯示 EAPV-AO 並未有種子傳播之現象；本研究另由員林地區採集所得之毛西番蓮罹染病毒病材料，經檢測鑑定均屬 EAPV-AO 所感染引起，進一步分析不同地理位置來源之百香果或毛西番蓮 EAPV-AO 分離株之鞘蛋白胺基酸序列之類緣關係，發現由員林所採集之毛西番蓮分離株自成一分群，而由埔里所分離之毛西番蓮分離株則與臺灣大坪頂的百香果分離株有較近的類緣關係，經田間觀察 PL 分離株來源之毛西番蓮周遭為百香果田區，有其百香果病毒來源之地緣關係。本研究另將不同百香果 potyviruses (包括 EAPV-IB 和 Telosma mosaic virus (TeMV)) 接種於健康毛西番蓮苗株，均能引起黃化嵌紋病徵，除印證毛西番蓮為百香果EAPV 病毒之寄主外，並首次證明其為 TeMV 之潛力寄主，可作為田間防治百香果病毒野生寄主之參考用。

 

林易賢、陳宗祺、陳煜焜。2021。玫瑰感染李屬壞疽輪斑病毒(Prunus necrotic ringspot virus, PNRSV)的發生。中華民國植物病理學會109年度年會論文摘要。植物醫學 63 (4): 49。 https://doi.org/10.6716/JPM.202112_63(4).0005

          玫瑰為薔薇科 (Rosaceae) 的作物，為世界上重要之園藝作物。有多種植物病毒，例如 Prunus necrotic ringspot virus (PNRSV)、apple mosaic virus (ApMV)、arabis mosaic virus (ArMV)、strawberry latent ringspot virus (SLRSV)、tobacco streak virus (TSV) 等，會在葉部引起多樣的病徵，包括嵌紋 (mosaic)、輪斑 (ringspot)、條斑 (line pattern)、斑駁 (mottle)、矮化 (stunt)、叢狀 (rossete)、變形 (distortion)。2020 年於嘉義番路鄉之有機玫瑰農園上發現在葉片帶有嵌紋及輪斑病徵的玫瑰，疑似由 PNRSV 所感染。將罹病葉片組織磨碎，機械接種於指示植物奎藜 (Chenopodium quinoa) 進行單斑分離，並未獲的單斑病毒株。由原始病葉進行總量RNA之萃取，使用 Malinowski and Komorowska (1998) 開發之 PNRSV 外鞘蛋白 (CP) 基因之專一性引子對 (PNRSV-CPF1: 5'-atggtttgccgaatttgcaatcat 和 PNRSV-CPR1: 5'-gagtgtgcttatctcactctag)，進行RT-PCR 檢測。預期之 cDNA 片段大小約為大小為 700 bp。由三次採集的總數 43 份標本中，可自 16 個樣本中增幅出預期大小的 cDNA 片段，檢出率 43%。選殖 RT-PCR 所增幅的cDNA 片段於 pCR Ⅱ Topo 載體，並送中興大學生科中心進行序列解析。解序結果顯示所選殖的片段全長 699 bp，涵蓋PNRSV CP ORF。經 NCBI 比對解序比對結果，顯示與 NCBI登錄的 PNRSV 病毒株的 CP 核苷酸和胺基酸序列相似度分別為98-99.23% 和 96.77-98.39%，最近似於 PNRSV isolate 143 coat protein (accession number DQ983498)，核苷酸和胺基酸序列相似度分別達 99.23% 和 97.49%，罹病率達 43%。在解序的同時也將罹病葉片組織磨碎，罹病組織粗汁液機械接種於奎藜、胡瓜及日日春，均未產生病徵，RT-PCR 檢測亦未自接種的供試植株檢出預期的 PNRSV 感染。以細菌表現載體 (pET-28b) 表現 PNRSV CP，將表現蛋白免疫注射於紐西蘭白兔以製備PNRSV 專一性抗血清，目前進行中。PNRSV 為 Bromviridae 科 Ilavirus 屬的病毒，於本國尚無發現之紀錄，但在國外的薔薇科重要果樹和花卉如蘋果、梨、桃、李、杏、櫻桃、玫瑰等是常見且重要的病毒。本次報告為 PNRSV 在臺灣的首次記錄。

 

劉亭君、蔡依真、謝佳珉、洪挺軒。2021。花蓮地區龍鬚菜病毒病田間發生與種類調查。中華民國植物病理學會109年度年會論文摘要。 植物醫學 63 (4): 49 - 50。 https://doi.org/10.6716/JPM.202112_63(4).0005

         龍鬚菜 (Sechium edule (Jacq.) Swartz.) 為花蓮吉安鄉特色作物，為全台主要產區，近年來病毒病之發生日益嚴重，逐漸受到農民重視。由於龍鬚菜之採收大多為連續摘取嫩芽，考量此採收方式有利病毒之機械傳播，本研究於吉安鄉採集帶有病毒病徵之葉片，針對瓜類常見之機械傳播病毒：胡瓜綠斑嵌紋病毒 (Cucumber green mottle mosaic virus, CGMMV)，矮南瓜黃化嵌紋病毒 (Zucchini yellow mosaic virus, ZYMV)，胡瓜嵌紋病毒 (Cucumber mosaic virus, CMV) 進行檢測，目前尚未發現上述病毒感染情況。經分子檢測田間多為南瓜捲葉菲律賓病毒 (Squash leaf curl Philippines virus, SLCPHV)，文獻上SLCPHV 為粉蝨傳播，另偵測田間粉蝨也可發現帶毒情形。於吉安鄉龍鬚菜田區設置黃色黏板偵測粉蝨族群，109 年 8 月族群數達到高峰，同年 11 月族群數開始明顯降低，至 110 年 1月數量最低。調查田間病毒罹病率，於 10 處龍鬚菜田區，每處隨機選取 200 棵植株觀察病徵有無，可見 109 年 5 月田間罹病率達到最高 (24.9%)，而後開始下降，至 110 年 2 月罹病率最低 (6.8%)，109 年 8 月田間罹病之龍鬚菜可見全株葉片均出現斑駁病徵，同年 10 月調查則部分新葉轉為正常無病徵，12月罹病株多數轉為正常，僅剩少數下位葉有病徵，此現象造成農民認為罹病株痊癒，但經 PCR 檢測，89%新葉仍能偵測到病毒，且一年生新植田之罹病率遠低於二年以上舊田，如何在考量成本效益下，有效防治 SLCPHV 於田間傳播將是未來重要課題。

 

          Welsh onion (Allium fistulosum L.) is one of the main vegetable crops in Taiwan. Comparing to other crop growers, Welsh onion planters are concern more on leaf diseases. Leaves of Welsh onion are subject to various fungal diseases such as anthracnose; purple blotch; rust and Stemphylium leaf blight (SLB). Purple blotch was considered the most prevalent foliar disease of Welsh onion in Taiwan. However, during 2018–2020, leaf blight symptoms somewhat similar to those described for purple blotch caused by A. porri were observed throughout Welsh onion fields in Sanxing, Taiwan. The severity of the disease varied among cultivars, causing up to 10% yield losses in most conventional and organic Welsh onion commercial fields. The initial symptoms consisted of either small, yellowish-brown to tan water-soaked lesions or whitish lesions with purple centres, which are very similar to purple blotch. When the disease was severe, the leaf spots merged and the leaves turned prematurely chlorotic and senescent, ultimately drying up and resulting in leaf dieback. For the past few decades, continuous application of fungicides recommended by Taiwan Agricultural Chemicals and Toxic Substances Research Institute (TACTRI) such as chlorothalonil, difenoconazole and iprodione was carried out to manage the foliar disease of Welsh onion fields in Sanxing, Taiwan. Moreover, in our recent field practice, we observed that these recommended fungicides and their commercial doses do not control the disease. However, correct species identification, epidemiology and control of leaf blight of Welsh onion is not well established, therefore, the main objective of this study was to investigate the causal agents of Welsh onion leaf blight in Sanxing and determine their pathogenicity. In this study, we surveyed the 27 Welsh onion fields located in seven villages commercial in Sanxing, Yilan. In total 769 diseased leaves were collected and among them, 394 lesions caused by Stemphylium sp. (51%), and 359 lesions caused by Colletotrichum sp. (47%). In the present study, 82 fungal isolates were obtained and preserved. During the field observation, two major types of lesions were observed, of which S. vesicarium caused limited oval leaf spots in light to dark brown, with a darker spot core producing spores, and Colletotrichum species caused light to dark brown leaf spot without a certain size and usually covering the whole leaf. Remarkably, we did not obtain Alternaria porri which was used to be the major pathogen causing leaf blight in Taiwan onion felids in our survey. The morph ological identification was based on features such as fungal colony, sexual or asexual spores and reproducing structures. Moreover, the molecular-based identifications were carried out via multi-locus sequence analysis, and the isolates were differentiated up to species level via polyphasic approaches. DNA alignments of multi-gene data set consists of ITS, gapdh, cal, and ITS, tub2, gapdh, were used to developed phylogenetic trees for Stemphylium and Colletotrichum, respectively. The isolates frequently obtained from fields were identified as Stemphylium vesicarium, Colletotrichum spaethianum (C. spaethianum species complex), and C. circinans (C. dematium species complex). To determine and compare the pathogenicity of each species, the inoculation of fungal isolates on the cultivar ‘Siao-Lyu’ was performed by spraying spore suspension onto the leaf surface. In this study, the Welsh onion plants were susceptible to all three species. Based on the results of disease incidence, we observed that Welsh onion plants were more susceptible to C. spaethianum compared to the other two species. Further, the mature leaves were more prone for leaf blight compared to younger leaves. Fungal strains used in the pathogenicity assay were re-isolated from infected leaves to determine their identity in order to confirm Koch's postulates and pathogenicity of S. vesicarium, C. spaethianum and C. circinans. In the present study, we carried out a comprehensive investigation and revealed the pathogenic association towards the Welsh onion foliar disease at fields in Sanxing, Yilan, Taiwan. This progress builds the key reference to developing accurate strategies for disease management.

 

          Twig dieback or branch canker of tea is a serious problem in tea gardens in Taiwan. Previous studies indicated that the twig dieback or branch canker are major caused by Macrophoma theicola Petch. However, other fungi, such as Fusarium or Phomopsis, are also reported to be pathogens that could cause dieback or canker in tea tree. According to the List of Plant Diseases in Taiwan, the tea dieback or canker could be caused by Cryptomyces theae, Macrophoma theicola, Nectria diversispora and Phomopsis sp. However, all of information might not enough to support the new situation in tea garden in Taiwan. Thus, reinvestigation and reidentification is necessary to carry out the major fungal pathogens causing tea dieback and their diversities in Taiwan. The samples were collected from January to November in 2020, including TTES No.12, TTES No.13, TTES No.18, TTES No.20, Sijichun, Chin-Shin-Oolong and Chin-Shin-Dapan locate in Nantou, Chiayi, Pingtung, Miaoli and Taoyuan. A total of 234 fungal isolates were obtained from the tea tissues showing dieback or canker symptom. The investigation showed that the percentage of tea dieback and canker is 0.67% ~30%. Based on morphology and molecular analyses, these fungal isolates could be identified as 10 genera in 7 familiae and the major genera are Diaporthe (36.8%), Cophinforma (22.2%) and Colletotrichum (11.5%). For pathogenicity test, the genera of Diaporthe, Cophinforma, Lasiodiplodia, Neofusicoccum,

Botryosphaeria, Pestalotiopsis, Colletotrichum and Fusarium could infect and cause twig blight symptom on one-year-old tea tree seedling (cv. Chin-Shin-Oolong) based on wound inoculation at 25℃ under 12 hr of light after 3 weeks of inoculation. Among these fungal genera, the Diaporthe spp. isolates are the main pathogens to cause dieback symptom (44%) on tea seedlings. For clarifying relationship of the Diaporthe isolates in our study, phylogenetic trees were constructed using sequences of internal transcribed spacers (ITS), translation elongation factor 1-alpha (EF1) and beta-tubulin (TUB). Results showed that Diaporthe isolates could be divided into 4 major clades. The non-pathogenic isolates were grouped as single clade with high bootstrap value (100%) and formed same clade with D. ueckera and D. miriciae. On the other hand, among pathogenic isolates clades, one of clade is closely related with D. tulliensis supported by a high bootstrap value (100%). The primary results indicated that the fungal isolates causing tea dieback or canker are high diversity in Taiwan.

 

          The genus Cephaleuros was named by Kunze in 1827 and accommodated in Trentepohliaceae. Species of Cephaleuros commonly occurs on leaves, stems and fruits of diverse trees and ornamental plants. It was considered as a plant disease pathogen causing red rust disease. Cephaleuros significantly reduces yields of tea and fruit trees, but there are few researches on these diseases. Cephaleuros virescens, the type species, has been recorded on at least 100 plant families in Taiwan. However, recent studies indicated that classification of Cephaleuros needs to be reassessed and found that morphological species of Cephaleuros are a polyphyletic species based on molecular phylogenetic analysis. A previous research found that Japanese C. virescens could be divided into 5 species, suggesting that C. virescens is a species complex. Thus, we planned to re-examine Cephaleuros spp. collected from Taiwan by molecular analysis, and to compare characteristics between clades. With phylogenetic analysis of sequences of SSU, ITS and LSU, we revealed that Cephaleuros in Taiwan can be separated into 11 clades. Besides, 13 new hosts were recorded with algal spots. Isolates phylogenetically closed to reference strains of C. parasiticus, C. karstenii and C. expansus were also found. Furthermore, since subcuticular and intercellular colonization of hosts are important characters to identify morphological Cephaleuros species, we will assess the correlation of the two colonization types with phylogenetic clades. Cephaleuros isolates with distinct colonization types were selected to compare biological characteristics related to pathogenicity and to elucidate the interactions of Cephaleuross and plants.

 

Dong, Z. -X. , Chen, Y. -K. , Chou, C. -C. , and Chen, T. -C. 2021. Diagnosis of a new emerging cucurbit virus using a Nanopore sequencing platform. Abstract of the 2021 Annual Meeting of Taiwan Phytopathological Society. Journal of Plant Medicine 63 (4): 70 - 71.   https://doi.org/10.6716/JPM.202112_63(4).0005

          Cucumber is a valuable economic crop in Taiwan. The planting area of cucumber in Taiwan was about 1893 ha with an annual yield of 48968 tons in 2019. In June 2020, an unknown virus, designated CX-2, was obtained from a diseased sample of greenhouse grown cucumber in Xizhou Township, Changhua County by standard single lesion isolation on Chenopodium quinoa leaves. Double-stranded (ds) RNA isolated from CX-2-infected C. quinoa leaves was used as the template to create a random primer-primed complementary DNA (cDNA) library, the Invitrogen SuperScript IV reverse transcriptase was use for cDNA synthesis and the Klenow fragment was used to synthesize the complementary strand of cDNAs. The synthesized dsDNAs were purified and ligated with sequencing adaptor using the Nanopore SQK-LSK109 ligation sequencing kit. The Nanopore MinIon device was used for sequencing, running for 8 hr. The sequenced reads were analyzed by the EPI2ME WIMP workflow. A total of 7408 reads were obtained from the sequencing, of which 13 reads were classified as cucumber Bulgarian latent virus (CBLV), a Tombusvirus species. The full-length genome sequence of the original CBLV isolate (GenBank accession number: AY163842) was used as a reference to align with the classified reads by the basic local alignment search tool (BLAST). The BLAST results showed that the reads shared a high nucleotide identity of 81.89-93.5% with the reference sequence, with a genome coverage of 68.4%. Our result suggests that CX-2 should be CBLV. The full-length genome sequence of CX-2 will be completed in the future.  

 

          2018年3月於彰化縣田尾鄉之宮粉仙丹葉片上，發現中央褐色壞疽且周圍具黃色暈環之葉斑型病徵，切取罹病葉片組織，置於光學顯微鏡下可觀察到細菌菌流，經分離純化獲得14株病原細菌。所得菌株於NA平板培養基上呈黃色黏稠狀菌落，為革蘭氏陰性、好氧性細菌，可於菸草葉片誘導產生過敏性反應，以105 CFU•ml-1細菌懸浮液噴霧接種於宮粉仙丹，可呈現與田間相同之病徵。利用生理生化特性測試及gyrase B序列分析鑑定為Xanthomonas axonopodis pv. maculifoliigardeniae。本病害在臺灣尚無推薦藥劑，以田間栽培常用藥劑進行測試，顯示以12.5%鏈黴素溶液及10%鏈四環黴素水溶性粉劑等抗生素類藥劑之抑制能力最佳。

 

草莓為一具有高經濟價值之作物，平均每分地產值約新台幣30 萬元。近幾年來主要栽種品種由桃園1 號（豐香）逐漸轉變為香水品種，雖然降低了炭疽病可能造成的危害，但亦促使新興病害 ”葉枯病”發生。葉枯病可危害草莓葉片、走蔓、根冠與果實，嚴重時造成30% 植株死亡。因此本研究利用葉枯病菌之ITS (internal transcribed spacer region)、β-tubulin 2 (TUB2 )、translation elongation factor 1 alpha (TEF-1α ) 與LSU (large subunit of the nrRNA region) 序列於NCBI 資料庫進行比對，顯示皆與Neopestalotiopsis rosae CBS101057 具有100% 之相同度。進一步，藉由個別基因與Neopestalotiopsis 屬之真菌進行類緣分析，顯示TEF 與TUB2 之單基因類緣樹圖譜具較高之解析度。在測試病原菌對藥劑敏感度方面，多種用於防治草莓炭疽病之殺菌劑皆具有較佳抑制葉枯病菌之菌絲生長效果，但部份strobilurin 類之殺菌劑則效果較差。於草莓品種之抗病性檢測方面，顯示桃園1 號（豐香）與苗栗1 號（戀香）為抗葉枯病之品種，而目前主要種植的香水草莓為感病之品種。據此，未來除了使用對葉枯病菌具抑制力之殺菌劑來防治本病之外，加速培育具有抗性之品種亦為一經濟有效之方法。

 

高雄區農業專訊117期: 12 - 14。 https://doi.org/10.29573/YYWYLL

        洋蔥植株蔥球肥大前，葉鞘捲曲及彎曲，逐漸萎凋，應屬炭疽病菌(Colletotrichum spp.)危害。

 

Phalaenopsis orchid (Phalaenopsis spp.) is an economically important ornamental crop in Taiwan. Collar rot caused by Athelia rolfsii (Curzi) CC Tu & Kimbr.(anamorph Sclerotium rolfsii Sacc.) is an important disease of orchid but not much is known in Taiwan. Severe …

 

Asparagus bean [Vigna unguiculata subsp. sesquipedalis (L.) Verdc.], belonging to Leguminosae family, is an important grain legume in many countries. In Taiwan, the cultivation is around 1,000 ha and it plays a critical role in vegetable production systems. During April 2020, a powdery mildew was observed on asparagus bean (about 100 plants) in a farm in Dacun, Changhua, Taiwan. The incidence on the leaves was 15–30% and the symptoms appeared as irregular colonies and white patches on both leaf surfaces. Under …

 

… In April 2020, a powdery mildew was observed on garden nasturtium in central Taiwan. Symptoms included angular chlorotic lesions which later became brown and necrotic on both leaf surfaces. The fungus was identified as Leveillulataurica s. str. based on the morphology and the molecular analysis of ITS sequence. The powdery mildew was found on both T. majus and sweet pepper in the meantime. …

 

…In total, six Diaporthe species, including one new species, Diaporthe hsinchuensis, were identified as linked with leaf spot of C. sinensis in Taiwan based on both phenotypic characters and phylogeny. … Diaporthe tulliensis, D. passiflorae, and D. perseae were isolated from C. sinensis for the first time. Furthermore, pathogenicity tests revealed that, with wound inoculation, only D. hongkongensis was pathogenic on tea leaves. …

(¹臺灣大學;  ²BiK-F, Germany;  ³Goethe University, Germany;  ⁴Chiang Mai University, Thailand; ⁵茶葉改良場;  ⁶King Saud University, Saudi Arabia)

 

          …The study revealed seven well-classified taxa and seven tentative clades in three genera: Pestalotiopsis, Pseudopestalotiopsis, and Neopestalotiopsis. One novel species, Pseudopestalotiopsis annellata, was introduced. Five new records, Pseudopestalotiopsis chinensis, Pseudopestalotiopsis camelliae-sinensis, Pestalotiopsis camelliae, Pestalotiopsis yanglingensis, and Pestalotiopsis trachicarpicola, were introduced for the first time in Taiwan. ….

 

…This is the first report of N. rosae causing leaf blight and crown rot in strawberry in Taiwan. N. rosae and N. clavispora have been reported as new threats to strawberry in several other countries (Gilardi et al. 2019; Rebollar-Alviter et al. 2020). Clarification of the pathogen provides a basis for developing strategies to control the emerging disease …

 

…the leaf disease of passion fruit in Taiwan was caused by S. passifloricola. This disease has been reported in Africa, India, Australia, New Zealand, the Caribbean, and South America (Cline 2006; Ploetz et al. 2003). If appropriate control actions are not taken, the disease may become a major leaf disease in nurseries in Taiwan.

 

Tang, W. Q., Chang, C. Y., Lee, Y. J., & Chu, C. C. 2021. First report of  Pectobacterium  aroidearum  causing bacterial soft rot of carrot in Taiwan.  Plant Disease 105 (3): 695.

…Occurrences of carrot soft rot in Taiwan have only been attributed to Dickeya spp. (Erwinia chrysanthemi) in previous studies (Hsu and Tzeng 1981). The present study is the first report of P. aroidearum infecting carrots in Taiwan. The findings may add to our understanding of the diversity of soft rot pathogens affecting carrot production in Taiwan.

 

Lin, S. R., Yu, S. Y., Chang, T. D., Lin, Y. J., Wen, C. J., & Lin, Y. H. 2021. First report of anthracnose caused by  Colletotrichum  fructicola  on tea in Taiwan.  Plant Disease 105 (3): 710.
https://doi.org/10.1094/PDIS-06-20-1288-PDN

…The fungus was reisolated from the diseased plants and identified as C. fructicola by resequencing of the four genes. To the best of our knowledge, this is the first report of anthracnose caused by C. fructicola on tea in Taiwan, although the pathogen has been present in China and Indonesia (Farr and Rossman 2020; Shi et al. 2018; Wang et al. 2016).

 

…This study confirmed P. xanthii as a causal agent of powdery mildew in Taiwan, and the awareness of the disease may benefit the floral industry. To our knowledge, this is the first confirmed report of P. xanthii on Z. elegans in Taiwan.

 

Wu, H. Y., Lai, Q. J., Wu, Y. M., Chung, C. L., Chung, P. C., & Lin, N. C. 2021. First report of  Xanthomonas  fragariae  causing angular leaf spot on strawberry (Fragaria × ananassa) in Taiwan. Plant Disease 105 (4): 1187.
https://doi.org/10.1094/PDIS-07-20-1631-PDN

… To our knowledge, this is the first report of X. fragariae causing angular leaf spot on strawberry in Taiwan. Currently, the disease only occurs severely in certain regions, but establishment of effective management strategies will be needed to prevent spreading of this disease and potential economic loss in the future.

 

Sheu, Z. M., Chiu, M. H., and Kenyon, L. 2021. First report of  Podosphaera xanthii  causing powdery mildew on mungbean ( Vigna  radiata ) in Taiwan.  Plant Disease 105 (6): 1856.
https://doi.org/10.1094/PDIS-09-20-2092-PDN

…The morphological characteristics were consistent with Podosphaera  xanthii (Castagne) U. Braun & Shishkoff  …To our knowledge, this is the first report of P. xanthii causing disease on mungbean in Taiwan. …Although both P. xanthii and E. polygoni have now been reported as causing powdery mildew on mungbean in Taiwan, which species predominates or is more important remains unclear. …

 

…Further analysis by BLAST revealed that SAP11 and phyllogen identified in symptomatic qing pi dou are identical with those of PnWB phytoplasma. To the best of our knowledge, this report is the first to describe phytoplasma-associated soybean (G. max) witches’ broom disease in green manure soybean in Taiwan.

 

…In Taiwan, species of family Cucurbitaceae such as loofah, bitter gourd, and pumpkin are commonly infected by 16SrVIII phytoplasma (Davis et al. 2017). In this study, we report for the first time that snake gourd, a species of family Cucurbitaceae, was infected by 16SrII-V PnWB phytoplasma in Taiwan.

 

          …based on morphology, molecular data, and phylogenetic relationship analysis the nematodes from the longan orchard were determined to be H. litchi. …This is the first report of H. litchi as a parasite of longan tree in Taiwan.

(中興大學)

 

…16SrII-V phytoplasma, a widely distributed phytoplasma associated with peanut witches’ broom disease in Taiwan, has also infected mungbean. This is not only the first instance of mungbean phyllody disease found in Taiwan but also the first instance of mungbean phyllody disease caused by 16SrII-V subgroup phytoplasma.

 

… the morphological and molecular characterizations supported the causal pathogen of Boston ivy leaf spot as D. tulliensis. …the emergence of D. tulliensis should be noted to avoid potential damage to economic crops.

 

          …To our knowledge, this is the first report of a 16SrII-V phytoplasma infecting sweet William in Taiwan. Since 16SrII-V phytoplasmas have also been found infecting mungbean and peanut in Taiwan (Liu et al. 2015), the findings here suggest that by serving as a natural host in the field, sweet William may potentially contribute to the spread of 16SrII-V phytoplasmas to food crops.

 

          … This is the first report of root and stem rot of wishbone flower caused by binucleate Rhizoctonia AG-L in Taiwan and in the world. Although this is the second case, since Wang and Hsieh (1993), for binucleate Rhizoctonia AG-L to be pathogenic, this study shows that this fungus has the potential to cause damage and is worth further investigation.

 

Lu, P. K., Liu, H. H., and Chang, H. X. 2021. First report of  Corynespora  cassiicola  causing target spot on soybean in Taiwan. Plant Disease 105 (11): 3753.  https://doi.org/10.1094/PDIS-02-21-0277-PDN

          …Based on the morphology, pathogenicity, and sequence results, this study becomes the first report of C. cassiicola causing target spot on soybean in Taiwan. C. cassiicola is known to infect a broad host range (Lopez et al. 2018), and it has been found to infect tomato, cucumber, papaya, and Salvia miltiorrhiza in Taiwan (Lu et al. 2019; Tsai et al. 2015). Therefore, the emergence of soybean target spot should be noted to avoid potential damage to soybean production in Taiwan.

 

Wang, C. H.¹, Tsai, Y. C. ², Tsai, I. ^1,3,4, Chung, C. L. ¹, Lin, Y. C. ¹, Hung, T. H. ¹, Suwannarach, N.⁵, Cheewangkoon, R. ⁵, Elgorban, A. M.⁶, and Ariyawansa, H. A. ¹ 2021.  Stemphylium leaf blight of Welsh onion ( Allium  fistulosum ): An emerging disease in Sanxing, Taiwan. Plant Disease 105 (12): 4121-4131.

          …This study discusses the emergence of SLB caused by S. vesicarium in the foliar disease complex affecting Welsh onion and the management of the disease using fungicides with different modes of action in Taiwan. The research will support the sustainable management of SLB in Sanxing, Taiwan; however, further field assessments of the fungicides are warranted.

 

……Cuphea carthagenensis, Cuphea hyssopifolia, Erigeron bellioides, Mazus pumilus, Phyllanthus tenellus, Salvia farinacea, and Sphagneticola trilobata were new hosts worldwide, whereas Bidens pilosa, Eclipta prostrata, Pouzolzia zeylanica, and Torenia fournieri were new hosts in Taiwan. …

 

        Erwinia chrysanthemi S3-1 is a bacterial soft rot pathogen of the white-flowered calla lily. The complete genome sequence of the strain was determined and used to reclassify the strain as Dickeya dadantii subsp. dieffenbachiae. …

 

          …this is the first report of crown gall disease caused by A. tumefaciens on H. sabdariffa in Taiwan. This disease may potentially damage the roselle industry if no action is taken to stop its spreading. …

(臺灣大學; 台東區農改場)

 

Lin, Y. C., Tseng, M. N., and Chang, H. X. (2022). First report of soybean seedling disease caused by  Rhizoctonia  solani  AG-7 in Taiwan. Plant Disease 106 (1): 314.  https://doi.org/10.1094/PDIS-01-21-0036-PDN

          …the molecular and morphological characterizations confirmed the causal pathogen as R. solani AG-7. R. solani AG-7 was first reported on radishes in Japan, first found on carnation in Taiwan, and has been found in field soils of various crops, but not soybean. … Rhizoctonia diseases of soybean may be present in Taiwan, … the importance of AG-7 as an endemic pathogen of soybean in Taiwan should be recognized and its prevalence determined as a first step to managing this disease.

 

Lin, C. P., Dai, Y. L., Huang, J. H., and Tsai, J. N. (2022). First report of tomato powdery mildew caused by  Leveillula  taurica  in Taiwan. Plant Disease, (ja).

Published Online:18 Jun 2021.  https://doi.org/10.1094/PDIS-02-21-0366-PDN

          …this is the first report of tomato powdery mildew caused by L. taurica. Typical lesions appeared in the beginning of the disease progress in the field. Through inoculation, the same pathogen could infect sweet peppers (Capsicum annuum L.), which has been also reported as a host of L. taurica (Tzen et al. 2019), suggesting these two crops could be alternate hosts of L. taurica in the field. Cross-species infection should be taken into consideration while managing the disease.

 

Duan, C. H., and Chen, G. Y. (2022). First report of  Colletotrichum  viniferum causing ripe rot of grape berry in Taiwan. Plant Disease, (ja).

Published Online:31 Aug 2021.

          … this is the first report of C. viniferum causing grape ripe rot in Taiwan.

 

Wang, Y. C., Liu, J. H., Huang, C. C., and Hong, C. F. (2022). First report of dragon fruit ( Hylocereus  undatus ) stem rot caused by  Diaporthe  ueckerae  in Taiwan. Plant Disease, (ja).

Published Online: 9 Nov 2021.

          …this is the first report of stem rot caused by D. ueckerae in Taiwan. Since the field symptoms may be easily confused with those caused by N. dimidiatum, the potential threat of Diaporthe species complex on dragon fruit should be aware and may warrant further study.

 

Liang, C. C., and Chen, P. J. (2022). First report of root-knot nematode  Meloidogyne  enterolobii  on poinsettia  ‘Luv U Pink’  in Taiwan.  Plant Disease, (ja).  

Published Online:24 Nov 2021.

          …this is the first report of M. enterolobii infecting E. pulcherrima ‘Luv U Pink’.

 

Duan, C. H., and Chen, G. Y. (2022). First report of  Colletotrichum  tropicale  causing anthracnose on common fig in Taiwan. Plant disease, (ja).

Published Online: 29 Nov 2021.  

          …… this is the first report of C. tropicale causing anthracnose on common fig fruit in Taiwan.

 

Ho, J. T., Liang, C. C., & Chen, P. J. (2021). First report of root-knot nematode  Meloidogyne  enterolobii  on cockscomb ( Celosia  argentea  var.  cristata )  in Taiwan.  Plant Disease, (ja).

Published Online: 2 Dec 2021.  https://doi.org/10.1094/PDIS-10-21-2126-PDN

          …cockscomb is the new host of M. enterolobii. To the best of our knowledge, this is the first report of M. enterolobii on Celosia argentea var. cristata in Taiwan.

 

Lin, C. C., Dong, Z. X., Tasi, Y. C., and Chen, T. C. 2021. Identification of a recombinant begomovirus infecting wax gourd ( Benincasa  hispida ). (董姿萱、林千琪、蔡依真、陳宗祺。花蓮地區葫蘆科作物之病毒病害調查)中華植物保護學會民國110年年會暨論文宣讀摘要集VD-4  2021年11月19日出版

Taiwan is located in subtropical and tropical regions, suitable for planting cucurbitaceous crops. Hualien is one of the main producing areas of cucurbitaceous crops, especially watermelon. A field survey for virus diseases of cucurbitaceous crops in Hualien area was conducted during two growing seasons from April to August 2021. Symptomatic bottle gourd, cucumber, sponge gourd, squash, watermelon and wax gourd samples were collected for virus detection, and a total of 100 samples were tested. Indirect enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) were performed to detect the prevalent cucurbit-infecting viruses in Taiwan, including cucumber mosaic virus (CMV), papaya ringspot virus watermelon type (PRSV-W), zucchini yellow mosaic virus (ZYMV), watermelon silver mottle virus (WSMoV), melon yellow spot virus (MYSV), squash leaf curl Philippines virus (SqLCPhV) and cucurbit chlorotic yellows virus (CCYV). Watermelon had the highest detection rate of WSMoV, as high as 41%, followed by MYSV, SqLCPhV, ZYMV and PRSV-W, each with a detection rate of 2%. In addition, SqLCPhV could be detected in bottle gourd, squash and wax gourd, with the detection rates of 67%, 71% and 100%, respectively. CMV and CCYV were not detected in all samples. Our result showed that SqLCPhV transmitted by silver leaf whitefly and WSMoV transmitted by Thrips palmi are the most prevalent cucurbit viruses in Hualien. SqLCPhV has a very wide host range and can infect a variety of cucurbitaceous crops, while WSMoV prefers watermelon.

 

Lin, Y. C., Lin, C. C., Chen, Y. K., and Chen, T. C. 2021. Detection of rose-infecting viruses via high throughput sequencing. (林鈺婕、林千琪、陳煜焜、陳宗祺。利用高通量定序技術檢測玫瑰病毒) 中華植物保護學會民國110年年會暨論文宣讀摘要集VD-5  2021年11月19日出版

Rose (Rosa spp.) is an important ornamental crop with multidisciplinary purposes. It can be used as cut flowers and potted flowers, as well as raw materials for cooking and essential oils. The annual output value of rose is around 25 million US dollars in Taiwan, and Nantou and Taichung are the major planting areas on this island. Rose mosaic disease (RMD) is a common rose disease caused by complex infection of several viruses including apple mosaic virus (AMV), apple necrotic mosaic virus, arabis mosaic virus (ArMV), prunus necrotic ringspot virus (PNRSV), strawberry latent ringspot virus (SLRSV), and tobacco streak virus (TSV). The infected plants show several severe symptoms such as mosaic, line patterns and ringspots on leaves. According to the official documents, the acreage of rose plantation in Taiwan has been decreasing due to serious pests and diseases. However, in the past few decades, no virus diseases have been reported in roses in Taiwan. In February 2021, rose plants with symptoms of mosaic, wrinkled leaves, leaf spots and chlorosis were observed at an organic rose farm in Chiayi. A total of 12 symptomatic rose samples were collected. Total RNA was extracted from rose leaf tissue as a template, and RNA-seq was performed by using the Illumina NovaSeq 6000 sequencing system for virus detection and diagnosis. The obtained reads were de novo assembled to generate 294 contigs for annotation. Ten species of 7 groups of viruses were detected, including three ilarviruses, two partitiviruses, and one each for capillovirus, carlavirus, closterovirus, luteovirus, and ourmiavirus. Virus-specific primer pairs were used to verify the presence of the viruses by reverse transcription-polymerase chain reaction. As a result, five viruses, i.e. AMV, PNRSV, rose partitivirus (RoPV), apple stem grooving virus (ASGV), and rose spring dwarf-associated virus (RSDaV) have been confirmed. A new ilarvirus closely related to tomato necrotic streak virus was also detected. This is the first report regarding virus infections on rose in Taiwan.

 

林玫珠、趙君皓、鄭櫻慧、蔡佳欣、陳金枝、林筑蘋。2021。感染葡萄之雙生病毒的分子鑑定與發生。中華植物保護學會民國110年年會暨論文宣讀摘要集VD-6  2021年11月19日出版 https://reurl.cc/l5mlkl

葡萄為台灣地區重要經濟果樹，主要以扦插進行無性繁殖，病毒易藉此苗木進行傳播。台灣已報導之葡萄病毒病害有葡萄扇葉病毒(Grapevine fanleaf virus, GFLV)、葡萄捲葉病毒(Grapevine leafroll–associated virus, GLRV)-品系1與葡萄A病毒(Grapevine virus A, GVA) ，媒介昆蟲分別為線蟲及介殼蟲，亦可經機械及嫁接進行傳播。2021 年 4 月，由台中外埔地區一有機葡萄園發現釀酒葡萄黑后品種之葉片呈現褪綠黃化、斑駁及捲曲之病徵，以 GFLV、GLRV 及 GVA 之專一性引子對進行分析，皆無病毒被檢測出。純化病葉之 RNA 以高通量定序進行 small RNA 之分析，序列經組裝後獲得一 2905 bp 之核酸片段，經資料庫分析比對後，證實為葡萄雙生病毒 A (Grapevine Geminivirus A，GGVA)，為 Geminiviridae 科Maldovirus 屬之植物病毒，其病毒顆粒為球型，具有一條環狀單股 DNA 基因體片段，同時複合感染一 Fabavirus。其中 GGVA 全基因組片段核酸序列與中國病毒株 2017YM1 (MT344703)、2019YM4 (MT344714)及 2019PD8 (MT344708)之相似度高達 99.9%，其次為日本病毒株 Pione (KX570616)，相似度為 99.6%。為了解 GGVA 在台灣之發生，調查主要產區台中后里、新社、外埔、南投信義、埔里及彰化大村、溪湖共計 14 個田區，169 個植株，以 GGVA 專一性引子對 GGVA C1F/R 進行分析及部分定序確認，其中共 141 個植株測得感染 GGVA，但多數植株並無病徵顯現。為釐清 GGVA 對葡萄之影響，由台中購買葡萄苗木欲進行嫁接，購得 30 株苗木，其中多感染 GGVA，且無病徵顯現，研判葡萄單獨感染GGVA 對其生長影響不大。而自埔里田區內雜草霍香薊亦觀察到病毒病徵，經核酸分析證實 GGVA 可以在雜草上繁殖，成為中間寄主。未來將研究 GGVA 與其他病毒複合感染對葡萄造成之影響。

 

Chen, J. H. , Tseng, Y. W. , Tu, C. K. , and Jan, F. J., 2021. Identification and occurrence of maize yellow mosaic virus (MaYMV) in Taiwan. (陳竟翰、曾意雯、杜紀寬、詹富智。臺灣玉米黃化嵌紋病毒之鑑定與發生)中華植物保護學會民國110年年會暨論文宣讀摘要集VD-8  2021年11月19日出版

In July 2020, maize (Zea mays) plants with leaf yellowing and mosaic symptoms were found in Daya District, Taichung City, Taiwan. Twelve symptomatic and one asymptomatic samples were collected from the field. Four viruses, including maize chlorotic mottle virus (MCMV, Machlomovirus), sugarcane mosaic virus (SCMV, Potyvirus), maize dwarf mosaic (MDMV, Potyvirus), and maize stripe virus (MSpV, Tenuivirus) have been reported to infect maize in Taiwan. Furthermore, a new polerovirus, maize yellow mosaic virus (MaYMV), was recently reported in East Asia. Reverse transcription-polymerase chain reactions (RT-PCR) with degenerate primer pairs for potyviruses and poleroviruses and specific primer pairs for MSpV and MCMV were performed to detect maize viruses. Results showed that all the 12 symptomatic samples were infected by MCMV, and one of them was also positive with the degenerate primer pairs for poleroviruses. All primers failed to amplify any products from the asymptomatic sample. A 1096-bp fragment amplified from partial RNA-dependent RNA polymerase (RdRp) of poleroviruses was cloned and sequenced. Sequence search in NCBI indicated that sequence of the new maizeinfecting virus in Taiwan shared 98.9%-99% nucleotide identities to those of MaYMV isolates. Specific primer pairs FJJ2020-127/ FJJ2020-128, which could amplify the full-length coat protein (CP) and movement protein (MP) of MaYMV were designed and used to confirm the presence of MaYMV. A 798-bp amplicon was amplified, cloned, and sequenced, revealing that sequence shares 99.7-100% nucleotide and 100% amino acid identities to CP of MaYMV and 99.7-100% nucleotide and 99-100% amino acid identities to MP of MaYMV isolates. Sequence analysis indicated that the virus infecting maize is an isolate of MaYMV. In the field survey, twenty-one symptomatic and fifteen asymptomatic samples were collected in Taichung City, Taiwan. RT-PCR with primers were used to detect potyviruses, MSpV, MCMV and MaYMV. Results showed that, of 21 symptomatic samples, four were infected with MaYMV, 10 by MCMV, four co-infected with MaYMV and MCMV, and three co-infected by MCMV and MSpV. A 798-bp fragment amplified from four different samples infected with MaYMV only was independently cloned and sequenced. Results showed that four sequences shared 99.1-99.5% nucleotide identities to each other and shared 99.2%-99.9% to MaYMV isolates available in GenBank. To our knowledge, this is the first report of maize infected by MaYMV in Taiwan.

 

林易賢、陳煜焜。2021。鳥尾花輪斑嵌紋病之病因探討。中華植物保護學會民國110年年會暨論文宣讀摘要集VD-9  2021年11月19日出版

鳥尾花(firecracker flower, crossandra) 為爵床科(Acanthaceae)鳥尾花屬(Crossandra)植物，為常見之園藝景觀花卉。2021 年 1 月於苗栗卓蘭花露農場發現具黃化輪斑和嵌紋等疑似病毒感染病徵之鳥尾花病株。初步鏡檢可觀察到病組織粗汁液含有數量眾多形似菸嵌病毒屬(genus Tobamovirus)之長桿狀病毒顆粒。使用 tobamovirus 簡併式引子對 Tob uni1/uni2進行 RT-PCR 偵測，可增幅出一段長 680 bp 的 cDNA 條帶。經序列解析後，發現該 cDNA序列涵括 Tobamovirus 屬之油菜嵌紋病毒(youcai mosaic virus, YoMV) (accession number: AY318866) 移動蛋白及外鞘蛋白之部分序列，且序列相似度達 98.38%，初步判斷該病害與YoMV 有關。病毒以奎藜(Chenopodium quinoa)進行單斑分離後，病毒分離株機械接種於鳥尾花(Crossandra sp.)和供試植物進行柯霍氏法則與寄主範圍測定。病毒接種於鳥尾花後約10 天，可在新葉觀察到黃化輪斑和嵌紋病徵；也可在多種茄科與十字花科植物，包括番茄、番椒、菸草、蘿蔔、青花菜、甘藍菜、油菜等經濟作物，引起系統性感染；而在木瓜、紫羅蘭等植物則引起局部感染。以 NCBI GenBank 已登錄的 YoMV 全長度基因體序列為模版，設計簡併式引子對進行全長度序列解析。結果顯示感染鳥尾花的 tobamovirus 基因體全長為 6304 個核苷酸，具有小複製酶(RNA replicase component) (nt 69 - 3380)、大複製酶(RNA replicase read-through component) (nt 69 – 4862)、移動蛋白(MP)(nt 4874 – 5671)和外鞘蛋白(CP)(nt 5595 – 6068)等 4 個開放讀框(ORF)，與 tobamoviruses 的基因體結構相符。比對鳥尾花病毒與 tobamoviruses 之基因體全長及各基因之核苷酸與胺基酸之相似度，結果顯示自鳥尾花分離的病毒與其他已知之 YoMV 分離株之全長基因體和各 ORF 核苷酸或胺基酸序列相似度均達 89%以上，其中全長度基因體核苷酸序列相似度 91.18-98.96%、小複製酶核苷酸/胺基酸序列相似度 89.25 - 98.88% / 95.01 - 98.91%、大複製酶核苷酸/胺基酸序列相似度 90.32 - 99.04% / 95.99 - 99.06%、移動蛋白核苷酸/胺基酸序列相似度 92.23 - 99.00% / 93.58 - 98.11%；外鞘蛋白核苷酸/胺基酸序列相似度 94.88 - 99.58% / 95.54 - 99.36%。病原性測定和序列分析的結果顯示鳥尾花輪斑嵌紋病是由 Tobamovirus 屬的 YoMV 所引起。在此之前，感染鳥尾花的病毒紀錄僅知有 tobacco streak virus (TSV, Ilarvirus)、alternenthera mosaic virus(AltMV, Potexvirus) 和 tomato leaf curl New Dehli virus (TLCNDV, Begomovirus)三種。我國有關 tobamovirus 的相關紀錄亦未及於 YoMV，故知 YoMV 是我國的新病毒紀錄，由 YoMV 感染鳥尾花所引起的輪斑嵌紋病是一新興病害。

 

蔡志濃、蔡惠玲、林筑蘋、安寶貞。 2021。兩種腐霉病菌引起之草莓幼苗萎凋病。 中華植物保護學會民國110年年會暨論文宣讀摘要集FD-6  2021年11月19日出版

大部分的腐霉病菌可寄生於植物種子、幼苗及老化階段的植株，使寄主植物產生猝倒 (damping-off disease)。腐霉病菌欲成功危害植物成為病原菌，主要取決所在環境中其接種 源密度、土壤溫濕度及與其他土壤微生物競爭能力的強弱。依據歷年田間草莓病害採集調 查，感染腐霉病菌之地下部根系稀少，甚而完全腐爛；地上部之莖基組織出現不規則褐變、 腐敗，葉片黃化、萎凋或枯萎，嚴重時全株死亡。將田間採集到的罹病樣本，先以自來水 沖洗其根系與莖基部表面，於病健部交界的病組織切成小塊 (7x7 mm² )，以 0.5% (v/v) 次 氯酸鈉 (NaClO) 水溶液進行表面消毒 10-30 秒，利用廚房紙巾吸乾組織表面的水份，該 消毒過的組織塊置於分離疫病菌常用之 5% CVA (Clarified V-8 juice agar) 半選擇性培養基 上進行培養。經由人工接種試驗完成柯霍氏病害鑑定結果顯示，有兩種腐霉菌 (Phytopythium helicoides and Pythium cucurbitacearum) 可以造成草莓幼苗植株萎凋。P. helicoides 在 5%V-8 培養基上的菌落為白色，無形成特殊花紋，具氣生菌絲。該菌生長快 速，生長溫度為 12-42℃，最適溫 32℃，直線生長速率為每日 3.37 cm。孢囊球形或橢圓 形，大小 15-35 × 20-35 μm。釋放游走子之孢囊可再生內生孢囊，約三次之多。P. cucurbitacearum 在 5%V-8 培養基上的菌落形成直線放射狀花紋，菌絲平鋪於培養基上， 氣生菌絲較少。生長溫度為 12-37℃，最適溫 28-32℃，直線生長速率為每日 1.64 cm。孢 囊球形或卵球形，大小為 7.5-12.5 × 5.5-10 μm。兩種腐霉病菌在單獨培養時均會形成卵孢 子，為同絲型。每一藏卵器約有 1-3 個藏精器附著，卵孢子非充實性。為了確認之病原性， 分別蒐集 P. helicoides 及 P. cucurbitacearum 之游走子懸浮液，以莖基部澆灌方法接種於 草莓 (豐香)之根系或莖基部，14-20 天後可以誘發病害，出現與田間相同之萎凋病徵；相同 病菌亦可從罹病組織回分得到。P. helicoides 及 P. cucurbitacearum 之 ITS1/5.8S/ITS2 基因 序列長度分別為 790 bp 及 841 bp，與 NCBI GenBank 資訊庫中腐霉病菌之的相同度分別 高達 99.88-100 %，顯示基因序列的比對結果與形態鑑定結果具一致性。

 

梁鈺平、林冠妤、賴素玉、倪蕙芳。台農 20 號鳳梨小果腐敗病之病徵及其真菌相之研究。兩種腐霉病菌引起之草莓幼苗萎凋病。 中華植物保護學會民國110年年會暨論文宣讀摘要集FD-7  2021年11月19日出版

鳳梨小果腐敗病 (fruitlet core rot) (或稱黑目病) 普遍發生於世界上許多鳳梨產區，於 台灣目前主要栽培品種中，以台農 20 號發生最為嚴重，造成嚴重損失。本研究於 2018 至 2021 年間調查台灣各地鳳梨小果腐敗病之病原菌種類，發現以 Talaromyces amestolkiae、T. stollii、T. funiculosus 及 Fusarium ananatum 為主。此些病原菌不同菌株間之菌落外觀多樣 化，且常複合出現於同一病斑，因此本研究設計此 4 種真菌之專一性引子，成功提高鑑定 之效率。此外，於台農 20 號鳳梨上，發病果目病徵有「乾腐」及「濕腐」兩種。為了解此 二種病徵是否係不同種類病原菌感染所造成，本研究於 2021 年 7 月至 9 月調查嘉義民雄 及大林地區共 3 批次之台農 20 號鳳梨乾腐、濕腐及健康果目，以及果實花腔內之真菌種 類，結果顯示 80%以上之健康果目無分離到真菌，而乾腐及濕腐病斑之真菌種類組成於各 批次比例有所不同，但 T. amestolkiae、T. stollii、T. funiculosus 及 F. ananatum 於兩種病徵 之果目均可分離到，因此病徵差異之原因還須更進一步研究。此外，花腔內真菌種類各批 次均以 T. amestolkiae 為主，F. ananatum 則極少。為進一步了解病原菌於田間之分佈是否有 所差異，本研究調查民雄同一田區共 8 個小區之鳳梨小果腐敗病斑上之真菌組成，發現 Talaromyces spp.及 F. ananatum 之比例於各小區間差異明顯，顯示病原菌於田間可能非均勻 分布。