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Jackfruit (Artocarpus heterophyllus) is an important fruit crop in Brazil, and it is commonly found in commercial plantations or spontaneous plants across the whole country. Anthracnose caused by Colletotrichumspp. is among the most important diseases of jackfruit. However, it is unclear which Colletotrichumspecies is responsible for this disease in Brazil. In 2018, in Goiás, Paraná and São Paulo states, and Distrito Federal (Brazil), jackfruit leaves presented necrotic foliar lesions with dark edges, light center, and chlorotic halo. Incidence of diseased leaves per plant was low (1 to 5%) and lesions were concentrated on the older leaves. Eight Colletotrichumisolates obtained from symptomatic leaves were assigned to the species C. siamensebased on phenotypical and molecular features. Their pathogenicity was confirmed by inoculation on jackfruit seedlings and reisolation of the pathogen from induced lesions. Also, the isolates were pathogenic to leaves of soursop, cashew, and mango, which indicates non-host specificity to the original host.

Fourteen Rhizoctoniaisolates obtained from coriander plants with symptoms of damping-off and web blight were collected in vegetable production areas between the years 2015 and 2017 in five geographical regions of Brazil. Identification was performed using phylogenetic analysis of the internal transcribed spacer region of ribosomal DNA, evaluation of morphological characteristics and pathogenicity test. Phylogenetic analysis revealed seven isolates belonging to the AG4-HGI group and two isolates to the AG2-2LP group; two isolates of the genus Rhizoctoniadid not group with any anastomosis group, representing a new lineage, and two Waiteasp. isolates and one binucleate isolate grouped with Ceratobasidium ramicola. Based on nuclear staining, thirteen isolates were multinucleated, while one isolate was binucleated. The isolates of Rhizoctoniaproduced irregularly shaped and brown sclerotia, while the Waiteaisolate produced orange sclerotia. In plants the formation of hymenia with the presence of unicellular basidiospores was observed. The basidiospore-producing fungus is represented by the new phylogenetic lineage of Rhizoctonia. All isolates were pathogenic in coriander seedlings, causing damping-off. This is the first report of Rhizoctonia solani(AG4-HGI and AG2-2LP), Waiteasp and C. ramicolain coriander in Brazil.

The knowledge about the array of host and non-host plant species of the cosmopolitan soil-borne pathogen Phytophthora capsiciis potentially useful in establishing efficient crop rotation systems. In the present work, pathogenicity bioassays were carried out aiming to re-examine the host range of P. capsiciusing 4 isolates obtained from taxonomically distinct species: snap bean, strawberry, bell-pepper and squash. Ninety-six plant accessions (72 species within 40 genera and 17 botanical families) were inoculated at seedling stage with zoospore suspensions. Reaction of fruits, pods, tubers, roots, or bulbs of 25 plant species was also determined. Twenty-two species were found to be susceptible to P. capsiciat the seedling stage, and 20 species displayed varying levels of fruit/pod/tuber/bulb susceptibility. We report one Cucurbitaceae (Sicana odorifera) and eight Solanaceae species: Physalis angulata, Solanum aethiopicumvar. gilo, S. betaceum(former Cyphomandra betaceae), S. chilense, S. paniculatum, S. torvum, Capsicum praetermissumand Nicotiana benthamianaas novel experimental hosts of P. capsiciat seedling stage. We also present the first formal report of Solenostemon autranii(Lamiaceae) as a new experimental host at seedling stage. Infection by at least one P. capsiciisolate was also reported for the first time in pods of cowpea (Vigna unguiculata) and in potato (S. tuberosum) tubers. Sechium edule(chayote) and Cucumis anguria(gherkin) were identified as novel cucurbitaceous hosts at the fruit stage, but these species were not infected by all isolates at seedling stage.An updated list of all currently reported hosts is provided.