番石榴枝枯病菌生物学特性及防治药剂筛选

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中图分类号：S482.2 文献标志码：A 文章编号：1001-411X（2026）03-0485-08

Biological characteristics of the guava twig blight pathogen and screening of its control fungicides

WU Caiyao'， YANG Wenli'，HE Gongwen’， YANG Guiqin'， ZHULili'， WEI Fengyue'，LI Minhui²， JIANG Dagang' （1 College ofLife Sciences， South China Agricultural University， Guangzhou ， China; 2 Collge of Plant Protection， South China Agricultural University， Guangzhou ， China）

Abstract： 【Objective】This study aims to clarify thebiological characteristics of Neopestalotiopsis egyptiaca， the causal agent of guava twig blight， and screen effective fungicides to provide a theoretical basis for disease control.【Method】 The effects of different culture conditions on fungal growth and conidial germination were determied through single-factor experiments.The inhibitory effects of six common chemical fungicides were evaluated using the mycelial growth rate method. 【Result】 The optimal mycelial growth was observed at 25°C，pH 5.0 ，and under 24h light exposure. In contrast， sporulation was significantly enhanced at 20°C ，pH 10.0， and under 12h light conditions. The optimal conidial germination occurred at 25∘C and pH 7.0 Furthermore， both mycelia and conidia exhibited certain salt tolerance. Among the six tested fungicides， thiophanate-methyl and pyraclostrobin showed the strongest inhibitory efects， with half maxmal effective concentration （EC50） of 0.6986 and 1.4054 μg⋅mL-1 ，respectively. Kasugamycin and mancozeb also demonstrated inhibitory activity， with EC50 of 244.4771 and 365.9905μg⋅mL-1 ， respectively. 【Conclusion】 N. egyptiaca exhibits strong adaptability， thriving across a wide range of temperatures and pH levels. In vitro toxicity tests indicate that thiophanate-methyl and pyraclostrobin are the most effective fungicides and should be prioritized for field control.

Keywords： Guava twig blight; Neopestalotiopsis egyptiaca; Biological characteristic; Fungicide screening

番石榴PsidiumguajavaLinn.，别名番桃、鸡矢果等，为桃金娘科Myrtaceae番石榴属Psidium热带果树，其原产地从墨西哥延伸到秘鲁，现广泛栽培于全球热带和亚热带地区[1-2]。（剩余8770字）