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Fungi belonging to the genus Cladosporium are cosmopolitan occurring in various substrate or hosts. Cladosporium spp. are responsible for economic losses in numerous agricultural crops, causing leaf spots, scab, postharvest rots and other disease symptoms. The etiology of many diseases associated with these symptoms is still uncertain. The aim of this research was to determine the identity of Cladosporium isolates associated with passionfruit scab and some postharvest rots on different crops in Brazil, based on phylogenetic and morphological analyses. The phylogenetic analyses indicated that all samples belong to the C. cladosporioides complex. Three previously described Cladosporium species were identified: Cladosporium pseudocladosporioides (on kiwi, passionfruit and taro), C. subuliforme (on passionfruit) and C. tenuissimum (on cashew fruit, papaya and passionfruit). In addition, four putative new species were found: Cladosporium passiflorae sp. nov., C. passifloricola sp. nov., Cladosporium sp. 1 and Cladosporium sp. 2, all occurring on passionfruit. This study is the first report of the presence of seven different species of Cladosporium associated with diseased passionfruit. Moreover, this paper represents the first report of C. pseudocladosporioides associated with postharvest rot on kiwi and taro and C. tenuissimum on cashew fruit in Brazil. This study contributes with several taxonomic novelties for the knowledge about the diversity of Cladosporium cladosporioides complex, especially those associated with plant diseases.

At poor conditions of nitrogen (N) in the soil, potato plants may accumulate starch in leaves and be indicative of N nutritional stress. The objective of this work was to determine the effects of N rates (0, 50, 100, 200 and 300 kg ha-1 of N) on the concentrations of carbohydrates (total soluble sugars-TSS, reducing sugars-RS, non-reducing sugars-NRS and starch) in the fourth leaf (FL) of two potato cultivars (Asterix and Atlantic) and their critical levels (CL) associated to the N fertilization rate necessary to obtain the maximum physical (MPE) and economic (MEE) efficiency of tubers. A randomized block design with four replications was used in both experiments. On day 21 after plant emergence, four FL were collected from four plants. Potatoes plants fertilized with low rates of N accumulated less TSS in leaves than those properly fertilized. The opposite occurred with content of starch. The cultivars showed similar responses to five doses of N in relation to contents of starch and TSS. However, the response to the increase in doses of N for RS, NRS and Starch/NRS is cultivar-specific. The correlations between contents of RS, NRS and Starch/NRS with the starch and TSS were dependent on the potato cultivar.

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