Fungi in the Botryosphaeriaceae family cause dieback, fruit rots, and stem cankers in many tropical fruit trees. To identify which species of Botryosphaeriaceae were present in tropical fruit in Puerto Rico and the symptoms they cause in rambutan and longan, a disease survey was conducted throughout the island from 2008 to 2016. Diseased organs of rambutan, longan, mango, and tangerine were collected and 39 isolates belonging to the Botryosphaeriaceae family were isolated and identified. Phylogenetic analysis of three nuclear genes identified nine species: six Lasiodiplodia spp. and three Neofusicoccum spp. All 39 isolates were inoculated on healthy 1-year-old rambutan and longan seedlings to confirm their pathogenicity. Dieback on both rambutan and longan was observed at 14 days after inoculation (DAI). Fourteen isolates from seven Botryosphaeriaceae species (Lasiodiplodia brasiliensis, L. hormozganensis, L. iraniensis, L. pseudotheobromae, L. theobromae, Neofusicoccum batangarum, and N. parvum) caused dieback in rambutan. Five of these pathogenic isolates were collected from rambutan, four from longan, two from mango, and three from tangerine. Ten isolates of four Lasiodiplodia spp. caused dieback in longan: L. hormozganensis, L. iraniensis, L. pseudotheobromae and L. theobromae,. Of these, three were collected from rambutan, three from longan, one from mango, and three from tangerine. Abundant development of pycnidia on branches, called corky bark, were observed on both rambutan and longan 60 DAI. Cross-inoculations showed that pathogenicity is wide in spectrum, indicating that different planting alternatives should be considered for better crop management.

Fruit rots reduce coffee production worldwide. Eight Colletotrichum species have been reported to cause coffee fruit rots; the most important is C. kahawae, the cause of coffee berry disease (CBD) in Africa. It is unknown whether these fruit rot pathogens can be dispersed by the coffee berry borer (CBB, Hypothenemus hampei) or whether Beauveria bassiana (a natural enemy of CBB) might reduce coffee fruit rots. We identified pathogens causing coffee fruits rots in Puerto Rico and evaluated whether B. bassiana reduced fruit rot and whether CBB could disperse pathogens. A total of 2,333 coffee fruit with CBB damage were collected; of these, 1,197 had visible growth of B. bassiana. C. fructicola, C. siamense, C. theobromicola, and C. tropicale were isolated and identified from the fruit using morphological traits and phylogeny of three nuclear genes. All four species caused internal and external rot after inoculation of healthy green coffee fruit. Coffee fruit treated with B. bassiana had significantly less fruit rot than untreated fruit, suggesting B. bassiana can protect against fruit rot. To test whether B. bassiana had a protective effect, B. bassiana and Colletotrichum were coinoculated on coffee fruit. Fruit inoculated with both B. bassiana and Colletotrichum had significantly less rot than fruit inoculated with Colletotrichum alone. To test if CBBs dispersed the pathogens, CBBs were exposed to Colletotrichum conidia and placed on green fruit, which resulted in fruit rot. This study identifies new pathogens causing coffee fruit rot, shows that C. kahawae is not the only Colletotrichum that attacks green fruits, suggests a role for B. bassiana in disease management and demonstrates CBB can disperse the pathogens.

Species in the genus Gliocephalotrichum (= Leuconectria) (Hypocreales, Nectriaceae) are soilborne fungi, associated with post-harvest fruit spoilage of several important tropical fruit crops. Contemporary taxonomic studies of these fungi have relied on morphology and DNA sequence comparisons of the internal transcribed spacer region of the nuclear rDNA (ITS) and the β-tubulin gene regions. Employing DNA sequence data from four loci (β-tubulin, histone H3, ITS, and translation elongation factor 1-alpha) and morphological comparisons, the taxonomic status of the genus Gliocephalotrichum was re-evaluated. As a result five species are newly described, namely G. humicola (Taiwan, soil), G. mexicanum (rambutan fruit from Mexico), G. nephelii (rambutan fruit from Guatemala), G. queenslandicum (Australia, endophytic isolations) and G. simmonsii (rambutan fruit from Guatemala). Although species of Gliocephalotrichum are generally not regarded as important plant pathogens, their ability to cause post-harvest fruit rot could have an impact on fruit export and storage.

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