First report of the fungus Fomitiporia maxonii Murrill causing citrus wood rot in commercial orange and grapefruit groves in Cuba R.I. Carbera a, * , C. Decock b , S. Herrera c , J. Ferrer a , I. Ortega d , S.A. Lopes e , V. Zamora a a Instituto de Investigaciones en Fruticultura Tropical, La Habana, Cuba b Mycothèque de l’Université catholique de Louvain, Earth and Life Institute e Microbiology (ELIM), Université catholique de Louvain, Belgium c Instituto de Ecología y Sistemática, CITMA, Cuba d Empresa Cítricos Ceiba, La Habana, Cuba e Fundecitrus, São Paulo, Brazil article info Article history: Received 20 May 2013 Received in revised form 15 January 2014 Accepted 17 January 2014 Keywords: Fomitiporia maxonii Incidence Citrus Wood rot abstract Cuban citriculture has recently been affected by important pests and diseases including black citrus aphid Toxoptera citricida Kirkaldy, citrus leafminer Phyllocnistis citrella Stainton, Asiatic citrus psyllid Diaphorina citri Kuwayama, Citrus tristeza disease, and huanglongbing. This complex of ‘invasive species’ is thought to be contributing to the increasing decline of commercial citrus groves. During several sur- veys carried out in commercial citrus areas of several provinces in Cuba, symptoms of dieback, charac- terized by the presence of abundant dry branches and wood rot were detected on Criolla Valencia orange, Marsh grapefruit trees on sour orange, and Cleopatra mandarin rootstocks. Samples of branches and trunk wood were processed and a fungus was isolated from all samples. Morphological, physiological and molecular characterization demonstrated that the isolated agent is Fomitiporia maxonii Murrill. The incidence of affected trees was high in most surveyed groves, reaching 100% in old groves. Symptoms similar to the ones found in naturally infected trees were reproduced on trees inoculated with pure cultures of the fungus, and the fungus was recovered in culture from inoculated trees, thus fulfilling Koch’s postulates. This is the first report of an association of F. maxonii with citrus wood rot in Cuba. Ó 2014 Elsevier Ltd. All rights reserved. 1. Introduction Since 1993, Cuban citriculture has increasingly been affected by important diseases and pests, including Citrus tristeza virus and its vector, the black citrus aphid Toxoptera citricida Kirkaldy (Batista et al., 1995), citrus leaf miner Phyllocnistis citrella Stainton, and more recently by huanglongbing and its most widespread vector, the Asiatic citrus psyllid Diaphorina citri Kuwayama (González, 2004). Multiple sprouting has been an additional important prob- lem caused by the broad mite Polyphagotarsonemus latus Banks (Cabrera et al., 2006). A recently detected disorder affecting trunks of young and old trees in commercial citrus groves in several provinces seems to have accelerated the decline of the trees already seriously affected by huanglongbing. The symptoms of this disease are characterized by a white inner rot with apparent lignin degradation that results in dry cracking. The margins of the lesions exhibit a dark stratum that circumscribes necrotic clear areas of variable outlines similar to those described by González et al. (2007) for symptoms associated with citrus infections by the basidiomycete fungus Fomitiporia punctata (Pilát) Murrill (cited as Phellinus punctatus Fr. ex Karst. Pilát) in Spain. The symptoms are also very similar to those described in citrus in Spain and Italy (Ippólito et al., 1998; Tuset et al., 2004; González et al., 2006) for diseases associated with another species of Fomitiporia, mainly Fomitiporia mediterranea M. Fisch., within the “Fomitiporia punctata” species complex (see Decock et al. 2007). F. mediterranea is a species considered to be restricted to the European continent. However, in Cuba and in the Caribbean, another species of this genus, Fomitiporia maxonii, was reported in Jamaican grapefruit (Citrus paradisi Macf.) under the synonym of Fomitiporia jamaicensis Murrill (Murrill, 1907, 1910). In Cuba, F. maxonii has been reported as Phellinus punctatus (Herrera Figueroa and Bondartseva, 1985), Fomitiporia punctata (P. Karst.) Murrill (Kotlaba and Pouzar, 2003) and, more recently, F. maxonii Murrill (Decock et al., 2007). However, no reference has been made so far on the symptomatology and damage associated with this organism in citrus groves under Cuban conditions. * Corresponding author. E-mail addresses: entomopatogeno@iift.cu (R.I. Carbera), cony.decock@ uclouvain.be (C. Decock), herrerafigueroa@ecologia.cu (S. Herrera), chino@ citricosceiba.cu (I. Ortega), slopes@fundecitrus.com.br (S.A. Lopes). Contents lists available at ScienceDirect Crop Protection journal homepage: www.elsevier.com/locate/cropro 0261-2194/$ e see front matter Ó 2014 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.cropro.2014.01.006 Crop Protection 58 (2014) 67e72