Xu Chuzhen, Zhang Jing, Zhou Jiangruihang, Zheng Yanyan, Huang Wei, Qin Dong, Huo Junwei, Li Yonggang
College of Plant Protection, Northeast Agricultural University, Harbin 150030, China.
National-Local Joint Engineering Research Center for Development and Utilization of Small Fruits in Cold Regions, Northeast Agricultural University, Harbin 150030, China.
J Appl Microbiol. 2023 Mar 1;134(3). doi: 10.1093/jambio/lxad025.
The aims of this study were to identify the pathogen causing blackcurrant leaf spot, assess the pathogenicity of different isolates, the host range, and the sensitivity to common fungicides, and test the effectiveness of field control for controlling A. alternata in blackcurrants in China, and potentially elsewhere.
In 2020 and 2021, an uncommon leaf spot on blackcurrants was observed in Harbin (125°42'-130°10'E, 44°04'-46°40'N), Heilongjiang Province, China. Based on morphological, molecular characteristics, and phylogenetic analyses, 10 fungal isolates, identified as Alternaria alternata, were obtained from infected blackcurrant leaves of 10 infected plants in this study. To our knowledge, this is the first description of A. alternata as a causal agent of leaf spot on blackcurrants in China. A. alternata has a wide host range and infects eight of the 10 crop and ornamental plants evaluated, namely Sorbus pohuashanensis, Malus pumila, Rosa davurica, Padus racemosa, Hippophae rhamnoides, Crataegus pinnatifida, Pyrus ussuriensis, and Sambucus williamsii, but not Viburnum trilobum and Prunus tomentosa. Moreover, ten blackcurrant cultivars were screened and found to have contrasting levels of resistance to A. alternata. One was moderately resistant, four were resistant, four were susceptible, and one was highly susceptible. The A. alternata isolate was most sensitive to propiconazole-azoxystrobin, with EC50 values of 0.0038 μg ml-1 and efficacy ranging between 83.34% and 84.13% at 317 μg ml-1 in the field.
The work reported that A. alternata is the pathogen that causes blackcurrant leaf spot in northern China. It can infect a variety of crops and ornamental plants. Considering the control cost and effect, propiconazole-azoxystrobin is more suitable for controlling leaf spot in the field.
本研究旨在鉴定引起黑加仑叶斑病的病原菌，评估不同分离株的致病性、寄主范围以及对常用杀菌剂的敏感性，并测试田间防治对中国乃至其他地区黑加仑中链格孢菌的防治效果。
2020年和2021年，在中国黑龙江省哈尔滨（东经125°42′ - 130°10′，北纬44°04′ - 46°40′）观察到黑加仑上出现一种不常见的叶斑病。基于形态学、分子特征和系统发育分析，从本研究中10株受感染的黑加仑植株的病叶中获得了10株真菌分离株，鉴定为链格孢菌。据我们所知，这是在中国首次将链格孢菌描述为黑加仑叶斑病的病原菌。链格孢菌寄主范围广泛，在所评估的10种作物和观赏植物中，它能感染其中8种，即花楸、苹果、刺玫蔷薇、毛山楂、沙棘、山楂、秋子梨和接骨木，但不感染三叶荚蒾和毛樱桃。此外，对10个黑加仑品种进行了筛选，发现它们对链格孢菌的抗性水平存在差异。其中1个品种中度抗病，4个品种抗病，4个品种感病，1个品种高度感病。链格孢菌分离株对丙环唑-嘧菌酯最为敏感，在田间浓度为317μg/ml时，其EC50值为0.0038μg/ml，防效在83.34%至84.13%之间。
该研究报道链格孢菌是中国北方引起黑加仑叶斑病的病原菌。它能感染多种作物和观赏植物。考虑到防治成本和效果，丙环唑-嘧菌酯更适合用于田间叶斑病的防治。
