The forest species are frequent targets of diseases. In this context, the plant-parasitic algae comprise a separate group in this process, including the algae genus Cephaleuros, which attacks mahogany cultivars. The objective of this work was to accomplish the molecular and morphological characterization of the causal agent of algae spots occurring in Brazilian mahogany (Swietenia macrophylla). Somatic and reproductive algae structures contained in lesions on the leaves had the DNA extracted and amplified by primers 18SHf and 18SLr of the rRNA nuclear gene 18S. Then, the amplicons were purified and sequenced. The algae structures too were characterized under light microscope. In addition, a total of 12 injured leaves located in the lower third of each attacked tree were randomly extracted for lesion characterization according to its size and number. After algae structures measurements, sporangiophores and sporangia had 260.2 x 12.9 μm and 25 x 18.8 μm. These measurements, combined with the molecular identification, indicated that the algae found in Brazilian mahogany leaves is C. virescens. Attacked leaves showed an average of 33 lesions, 60% of which were smaller than 2 mm in diameter, which shows great capacity of the pathogen to reach different parts of the foliar limb. These measurements, combined with molecular identification, confirmed the algae found in Brazilian mahogany leaves to be C. virescens.

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Objetivou-se identificar o melhor tipo de recipiente e ambiente para crescimento e produção de mudas de Acacia mangium Willd. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 2 x 3 em dois ambientes de cultivo (coberto com plástico filme e com tela Sombrite® 50%) e três tipos de recipientes (tubetes de 120, 290 e 820 cm³), com 21 repetições cada. Avaliou-se: primeira contagem de emergência, emergência total, índice de velocidade de emergência, altura de plantas, diâmetro do caule das plantas, matéria fresca e seca da parte aérea e raiz, índice de qualidade de Dickson e índice relativo de clorofila. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Para as análises estatísticas utilizou-se o programa R Core Team. As mudas produzidas em ambiente coberto com plástico filme e no tubete de 820 cm3 apresentaram os melhores resultados.

Diseases are considered one of the main factors that limit the productivity of the Eucalyptus sp. Thus, the objective was to carry out a scientometric analysis of the articles, focusing on the eleven main pathogens that affect the eucalyptus culture. For the development of this study, specialized searches were carried out on the “Web of Science” database using the scientific names of pathogens and eucalyptus as key words. In the general search, a result of 123 articles published between 2000 and 2020 was obtained, with Mycosphaerella spp., Ceratocystis fimbriata, Botryosphaeria ribis and Cylindrocladium spp., The pathogens with the highest number of published works and also citations. Regarding the citations / article, Botryosphaeria ribis (average of 68.80 citations / article), Mycosphaerella spp. (average of 34.57 citations / article) and Cylindrocladium spp. (average of 27.12 citations / article). Regarding the journals, a total of 38 journals were responsible for the published works, with nine of them concentrating 60% of the total of published articles.

O uso incorreto de agrotóxicos no Brasil e no mundo tem trazido sérias consequências, tanto para o meio ambiente quanto para a saúde do trabalhador rural. O presente trabalho teve como objetivo avaliar a percepção dos produtores de banana-maçã da região de Itaguaru-GO através de questionários relacionado ao conhecimento deles acerca da utilização dos agrotóxicos, uso de EPI’s, armazenamento e assistência técnica agronômica. Os resultados apontam o pouco conhecimento dos trabalhadores rurais quanto ao tema, a maioria deles encontra dificuldade para ler as bulas dos vasilhames dos produtos químicos e ainda o pouco conhecimento ao se tratar do uso de EPI’s e da importância da assistência técnica agronômica.