A Novel Molecular Identification Technique for Lasiodiplodia species Associated with Avocado Diseases in Taiwan

Yu-Ping Liang; Hui-Fang Ni

doi:10.6156/JTAR.202512_74(4).0006

A Novel Molecular Identification Technique for Lasiodiplodia species Associated with Avocado Diseases in Taiwan

Other Title

臺灣酪梨上之Lasiodiplodia屬病原菌之新穎分子鑑定技術

Journal

台灣農業研究

Journal Volume

74

Journal Issue

4

Start Page

459

End Page

484

ISSN

2790-086X

Date Issued

2025-12-06

Author(s)

Yu-Ping Liang

嘉義農業試驗分所

Hui-Fang Ni

嘉義農業試驗分所

DOI

10.6156/JTAR.202512_74(4).0006

URI

https://scholars.tari.gov.tw/handle/123456789/24943

Abstract

Lasiodiplodia theobromae and L. pseudotheobromae are widely distributed plant pathogens in tropical and subtropical regions, causing numerous diseases, but they are not easily identified and distinguished by traditional morphological techniques. In this study, we developed two species-specific primer pairs (Lt-F2/Lt-R1 and Lp-F/Lp-R2) based on sequence differences in translational elongation factor 1-α (TEF1-α) among Lasiodiplodia species. Polymerase chain reaction (PCR) amplification from genomic DNA verified that Lt-F2/Lt-R1 and Lp-F/Lp-R2 were specific for L. theobromae and L. pseudotheobromae, respectively; no amplification was observed from nontarget species. Using these primers to amplify DNA from 54 Lasiodiplodia isolates from avocado (Persea americana) in Taiwan, we successfully identified isolates of L. theobromae and L. pseudotheobromae. Meanwhile, we also detected the presence of other unknown Lasiodiplodia spp. Phylogenetic analyses using the DNA sequences of TEF1-α, β-tubulin 2 (TUB2), and RNA polymerase subunit II (RPB2) from these unknown species showed that L. thailandica, L. hormozganensis, and other unidentified Lasiodiplodia species also occurred on diseased avocado fruits, branches, or pedicels in Taiwan; their pathogenicity to avocado was confirmed on fruits. L. thailandica was reported as a pathogen of avocado for the first time, and the specific primers designed in this study provide a valuable tool for identifying the two Lasiodiplodia species.

Lasiodiplodia theobromae 與 L. pseudotheobromae 為廣泛分布於熱帶與亞熱帶之植物病原菌，造成許多作物病害，但兩者不易透過傳統型態學方法鑑定與區分。本研究根據 Lasiodiplodia 屬物種間之轉譯延長因子 1-α (translational elongation factor 1-α; TEF1-α) 序列之差異性，開發了 2 對物種專一性引子對 (Lt-F2/Lt-R1 與 Lp-F/Lp-R2)。以基因體 DNA 進行聚合酶連鎖反應，結果顯示 Lt-F2/Lt-R1 與 Lp-F/Lp-R2 分別對 L. theobromae 與 L. pseudotheobromae 具有專一性，對於非標的物種則均無擴增反應。使用此二引子增幅分離自臺灣酪梨 (Persea americana) 的 54 株 Lasiodiplodia 菌株之 DNA，成功自其中鑑定出屬於 L. theobromae 與 L. pseudotheobromae的菌株，然有些菌株則無法被以上二對引子增幅，顯示臺灣酪梨上存在其他未知的 Lasiodiplodia spp. 病原。進一步以 TEF1-α、β 微管蛋白 2 (β-tubulin 2; TUB2) 及 RNA 聚合酶 II (RNA polymerase subunit II; RPB2) 之基因序列進行以上未知菌株之親緣分析，結果顯示另有 L. thailandica、L. hormozganensis 及目前尚無法以此親緣關係鑑定的 Lasiodiplodia 物種存在於臺灣之罹病酪梨果實、枝條及果梗，經病原性試驗後顯示以上三者對酪梨果實均有病原性。本研究首次報導 L. thailandica 為酪梨之病原菌，且本研究開發之專一性引子將可於未來作為鑑別常見病原 L. theobromae 與 L. pseudotheobromae 的有效工具，有助於研擬正確防治策略。

Subjects

Lasiodiplodia hormozganensis

Lasiodiplodia thailandica

Lasiodiplodia theobromae

Lasiodiplodia pseudotheobromae

Species-specific primers

專一性引子

Publisher

農業部農業試驗所

Type

journal article

File(s)

Name

74-4-6.pdf

Size

11.19 MB

Format

Adobe PDF

Checksum

(MD5):7e0ec6027bcaeed84d8367b27379c28c