First Report of Lasiodiplodia theobromae Causing Needle Blight and Stem Canker Diseases on Araucaria heterophylla in Ethiopia

Abstract

Canker and needle blight of Araucaria heterophylla (Norfolk Island pine) trees were observed during the surveys conducted in Addis Ababa and Adama cities (Ethiopia) from November to December 2016. The main objective of this study was to investigate fungal pathogens that cause diseases on Araucaria heterophylla trees. Six localities with Araucaria heterophylla plantings were purposively surveyed for disease symptoms. Samples from symptomatic parts of trees were collected, surface sterilized, cultured on PDA and morphologically identified for genus and species. A total of 36 isolates of fungi were identified. Based on macro- and microscopic morphological features of the colonies, the fungal isolates were found to be the genus Diplodia and species Lasiodiplodia theobromae (Pat.) Griffon & Maubl (syn. Botryodiplodia theobromae), the anamorph of Botryosphaeria rhodina (Berk. & M.A. Curtis) Arx. The pathogenicity test showed that the isolates of Lasiodiplodia theobromae, caused stem canker and needle blight on Araucaria heterophylla. This finding is important in the study of management options for future prevention and control of diseases in the country.

Molecular Characterization and Disease Control of Stem Canker on Royal Poinciana (Delonix regia) Caused by Neoscytalidium dimidiatum in the United Arab Emirates

“…Although it is known for its ability to withstand severe conditions, diseases are major factors that affect the health of royal poinciana [3,4]. Many of the phytopathogens can cause diseases on host plants, including royal poinciana [5][6][7][8]. Therefore, careful attention should be attained to the causal agent of stem canker disease on royal poinciana, taking into account the frequency of disease incidence, the geographical distribution and the environmental conditions favorable to the disease occurrence.…”

“…In general, we noticed dieback, canker and gummosis, which ultimately led to complete dryness and death of royal poinciana trees (Figure 1). Although some studies have reported several fungi to cause cankers on plant species [5][6][7][8], others have recorded N. dimidiatum on almond, dragon fruit, eucalyptus, fig and plum, displaying disease symptoms of canker and dieback in different places of the world [13][14][15]28]. In general, environmental stress has negative impact on the severity of disease, depending on the level and duration of the stress, and the sensitivity and developmental stage of the plant species.…”

“…In general, cankers are destructive diseases which may cause damage to the whole or parts of trees such as branches, barks and woods. Fungi such as Nectria galligena, Leptosphaeria maculans, Lasiodiplodia theobromae and Teratospheria zuluensis are among those associated with canker diseases on sweet birch tree (Betula lenta), oilseed rape (Brassica napus), eucalypt and pine trees [5][6][7][8]. Neoscytalidium dimidiatum is another fungal pathogen that causes cankers and has a wide geographical and host range, including plum, almond (Prunus dulcis), mango (Mangifera indica), pitahaya (Hylocereus undatus), Citrus, Musa, Populus, and Ficus spp.…”

Antibacterial activity of endophytic fungi in Pometia pinnata against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus

“…This fungus is an oftenencountered endophyte and an opportunistic pathogen causing disease when its host is in unfavorable condition. L. theobromae can live in more than 500 species of tropical and subtropical plants (Darge 2017). L. theobromae isolated from the Piper hispidum Sw plant has antibacterial activity against some bacteria species (Orlandelli et al 2012).…”