目前台灣地區梨黑星病菌之鑑定與其對藥劑的感受性

Identification and Fungicidal Sensitivity of the Fungus Venturia sp. the Causal Agent of Pear Scab in Taiwan

吳舒雅(S. Y. Wu) ； 鍾文全(W. C. Chung) ； 黃振文(J. W. Huang) ； 石井英夫(Ishii H) ； 鍾文鑫(W. H. Chung)

《植物病理學會刊》 18卷3期 (2009/09) Pp. 135-143

https://doi.org/10.6649/PPB.200909_18(3).0002

摘要

爲釐清台灣梨黑星病菌之種類，本研究自新竹新埔、台中新社及梨山共蒐集78株梨黑星病茵株，經孢子形態的觀察，顯示台灣梨黑是病菌與Venturia nashicola之形態類似。另將核糖體核酸(rDNA)內轉錄間隔區(ITS1/ITS2)與5.8S核酸片斷定序後，以maximum parsimony (MP)與neighbor-joining (NJ)法分析，證實所供試39株台灣梨黑星病菌與GenBank中之V. nashicola同屬一個分子群，而與V. pirina分屬不同的分子群。此外於馬鈴薯葡萄糖瓊脂培養基(potato dextrose agar, PDA)中測試梨黑星病菌對5種不同殺菌劑之抗感性，得知克熱淨(iminoctadine)與撲克拉錳(prochlorate manganese)對所有供試菌株菌絲生長抑制之EC50值小於10μg/ml有效濃度；免賴得(benonyl)對所有供試菌株菌絲生長抑制之EC50值小於100μg/ml有效濃度。雖然克收欣(kresoxim-methyl)與三氟敏(trifloxystrobin)於對96%以上之洪試菌株菌絲生長抑制之EC50值小於l00μg/ml有效濃度，但仍有3株供試菌株之EC50值大於100或500μg/ml有效濃度，表現低感受性。

關鍵字

梨黑星病 ； 抗感性 ； 殺菌劑 ； ITS1/ITS2

並列摘要

To identify the species of pear scab caused by Venturia sp.. we examined the morphological and molecular characteristics of the fungus Venturia sp. collected from Sinpu, Hsinchu County. Shishe, Taichung County and Lisan, Taichung County. Morphological results showed that the fungus belongs to V. nashicola. In the genetic analysis, the internal transcribed spacer (ITS1/ITS2) and 5.8 S regions of ribosomal DNA also conformed to the results of the morphological examinations of V. nashicola based on maximum parsimony (MP) and neighbor-joining (NJ) analysis with 94% and 88% bootstrap support. A total of seventy eight isolates of Venturia sp. from three places in Taiwan were examined for their sensitivities to iminoctadine, prochlorate manganese, benomyl, kresoxim-methyl and trifloxystrobin in PDA medium. Iminoctadine and prochlorate manganese inhibited mycelial growth of all V. nashicola isolates with EC50 values ＜ 10μg/ml. whereas benomyl inhibited mycelial growth of all V. nashicola isolates with EC50 values ＜ 100μg/ml. Although kresoxim-methyl and trifloxystrobin inhibited more than 96% V. nashicola isolates with EC50 values ＜ 100μg/ml, three isolates of V. nashicola showed low sensitivities in 100 or 500μg/ml.

並列關鍵字

pear scab ； sensitive/resistant ； fungicides ； ITS1/ITS2