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Recent reports of plant diseases that result in yield reduction and increasing demand for dragon fruits raise concerns of fruit supply shortage. Emerging plant diseases may play an important role in increasing yield losses and reducing the availability of stem cuttings (source of planting materials). Understanding the aetiology of current and new diseases of dragon fruit is important to address production issues and to formulate effective disease control measures. This study reports Epicoccum sorghinum as a potential emerging pathogen of dragon fruit. Epicoccum sorghinum MBDF0024a was isolated from dragon fruit stems (Hylocereus monacanthus) showing brown spot symptoms. DNA sequence of the internal transcribed spacer (ITS‐rDNA), beta tubulin and actin gene regions of fungal isolate MBDF0024a had high similarities to E. sorghinum stains. Epicoccum sorghinum MBDF0024a was pathogenic to three cultivated dragon fruit species (Hylocereus undatus, H. monacanthus and H. megalanthus) in repeated laboratory and glasshouse trials. Large brown lesions developed on 3‐week‐old inoculated rooted stem cuttings 3 days postinoculation (dpi). Yellowing of the lesion (advance part) started at five dpi, and at seven dpi, yellowing was observed in the stem. As there are no reported control measures for diseases caused by E. sorghinum, this study screened chemicals with antifungal properties. A biopesticide containing B. subtilis (2 ml/400 ml), and chemicals isoprothiolane (2.25 ml/400 ml), mancozeb (2 g/400 ml) and pyraclostrobin (1 ml/400 ml) (chemical control) completely inhibited the in vitro growth of E. sorghinum MBDF0024a. The results establish E. sorghinum as a new and emerging pathogen of dragon fruit that could be a major yield‐limiting disease if left uncontrolled. The biopesticide can be considered a fairly safe option for disease management, but glasshouse and field studies are needed for validation.

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Diseases are among the major problems that negatively affect dragon fruit profitability worldwide. Diseases of dragon fruit in the Philippines are yet to be identified and reported. This study elucidates the causal agent of a disease infecting stems of dragon fruit grown in Los Baños, Laguna, Philippines. The fungus was isolated and identified as Nigrospora sp. based on morphological and cultural characteristics in potato dextrose agar medium. Using the DNA sequence of the internal transcribed spacer (ITS) gene region, isolate MBDF0016b was identified as Nigrospora sphaerica. The Philippines strain was closely related to the Malaysian strain, which also causes reddish-brown spot in dragon fruit (H. polyrhizus), and to other N. sphaerica isolates from other host-plant species. Nigrospora sphaerica MBDF0016b was pathogenic to H. megalanthus, H. undatus, and H. polyrhizus in detached stem and glasshouse assays. The same fungus was re-isolated from the inoculated stems and thus, establishing Koch’s postulate. This paper is the first confirmed scientific record of a dragon fruit disease in the Philippines and the first report of N. sphaerica as a dragon fruit pathogen causing reddishbrown spot disease in H. megalanthus.

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Dragon fruit (Selenicereus spp.) is a high‐value crop in the Philippines. It is commonly propagated using stem cuttings, which quality is essential for fruit production. Several pathogens have been reported to cause various diseases in dragon fruit worldwide. These diseases affect stem and fruit quality in the field, but the consequences during storage are unknown. This study aims to determine the effect of three pathogens (Neoscytalidium dimidiatum, Epicoccum sorghinum, and Nigrospora sphaerica) on Selenicereus stem cuttings in controlled storage conditions. Three weeks after inoculation, only N. dimidiatum significantly reduced Selenicereus stem weight in both cooler (air‐conditioned storage area/19‐25°C) and warmer (room temperature/28‐30°C) temperatures. Nonetheless, all pathogens induced symptoms on stems, which caused a loss in product quality. Neoscytalidium dimidiatum caused significantly more severe symptoms under controlled conditions. In general, symptoms were more severe on the stems kept in the air‐conditioned storage area. This study highlights the importance of disease‐free planting materials and adequate temperature in the storage area in the preparation and dissemination of high‐quality dragon fruit stem cuttings.

The commercially known persimmon fruit came from the genus Diospyros in the family Ebenaceae. Four species of persimmon, namely D. oleifera, D. virginiana, D. lotus and D. kaki (Kitagawa & Glucina, 1984), dominate the current commercial production.Persimmons have high nutritional content, such as sugars, vitamin C, carotenoids and polyphenol, that plays a major role in the human diet (Giordani et al., 2011). The Philippines does not cultivate persimmon, so fruits are imported from countries like Korea, China, Hong Kong, New Zealand and Spain (UN Comtrade Database, 2021). In 2020, the country imported 1,207 metric tons of persimmon fruits (valued at 2,192,687 USD), with Korea being the dominant supplier accounting for 83% of the total imports (UN Comtrade Database, 2021). From 2015 to 2019, the production of persimmons worldwide had a minor drop from 4.3 million tonnes to 4.2 million tonnes (FAOSTAT, 2019).Anthracnose is a plant disease in which most cases are attributed to the genus Colletotrichum. The disease is characterized by dark, sunken, necrotic lesions observed on young and mature plant parts (Freeman et al., 1998). The disease can be observed at any stage of plant growth and may wipe out an entire orchard and result in reduced fruit harvest. Moreover, anthracnose symptoms can also be seen in postharvest conditions that cause major reductions in fruit yield and quality. In persimmon, different Colletotrichum species in the acutatum, boninense, gigasporum and gloeosporioides species complexes that cause anthracnose worldwide have been reported

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