Identification, pathogenicity and distribution of the causal agents of dieback in avocado orchards in Spain

Spanish Journal of Agricultural Research

Carlos J. López-Herrera¹  Isabel Arjona-Girona²  David Ruano-Rosa³ 

[1] Finca Zamadueñas, 47071, Valladolid;CSIC, Instituto de Agricultura Sostenible, Dept. Protección de Cultivos, C/Alameda del Obispo s/n, 14004, Córdoba;Instituto Tecnológico Agrario de Castilla y León, Unidad de Cultivos Leñosos y Hortícolas, Ctra. De Burgos km 119

关键词: Botryosphaeriaceae;    Lasiodiplodia;    Neofusicoccum Colletotrichum Persea americana;   

DOI  :  10.5424/sjar/2019171-13561

学科分类：农业科学（综合）

来源: I N I A

【 摘 要 】

An increased incidence of dieback from branches in several avocado orchards in southern Spain was observed in 2014. Surveys were conducted from May to October 2014, sampling the affected branches to isolate the causal agents. A total of 68 fungal isolates, recovered from ten avocado orchards, were identified, by morphological characterisation and DNA sequencing, as belonging to the genera:Neofusicoccum parvum(50%),Colletotrichum gloeosporioides(17.6%),Neofusicoccum luteum(16.2%),Neofusicoccum australe(13.2%),Neofusicoccum mediterraneum(1.5%) andLasiodiplodia theobromae(1.5%). A decreasing level of virulence in artificial inoculations on avocado plants was observed inN. parvum, N. luteum, N. mediterraneum, N. australe, C. gloeosporioidesandL. theobromae , there were significant differences amongN. parvumand the rest of species of this genus, and significant differences were only observed betweenN. luteumandC. gloeosporioides . The geographical distribution ofN. parvumandN. Luteumcovers different areas, whileC. gloeosporioidesandN. australeare located only in the areas around Benamocarra and Vélez-Málaga (southern Spain), whileN. mediterraneumandL. theobromaeappear only occasionally. This is the first study of avocado branch cankers in Spain which identifies the causal agents and establishes their pathogenicity groups, withN. parvumas the most important causal agent of avocado dieback in this area.

【 授权许可】

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