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O objetivo do trabalho foi avaliar o potencial de rizobactérias e Trichoderma spp. no controle biológico de Bursaphelenchus cocophilus. Foram avaliados 19 isolados de Pseudomonas spp. (P), 29 de Bacillus spp. (B) e 27 de Trichoderma spp. (T), obtidos de plantio comercial. Os isolados foram caracterizados quanto a produção de compostos bioquímicos. Foi avaliada a taxa de mortalidade de B. cocophilus in vitro e in vivo, neste último realizou-se também a quantificação das enzimas relacionadas à patogênese. Os isolados B14 e P41 proporcionaram 69% e 56% de taxa de mortalidade de nematoides, respectivamente e foram tanto proteolíticos como solubilizadores de fosfato. Os isolados T41 e T54 apresentaram 96% de mortalidade de B. cocophilus in vitro e foram produtores de quitinases, protease e sideróforos. No experimento in vivo, os isolados de rizobactérias B14, B23 e P23 promoveram maior taxa de mortalidade do B. cocophilus do que os demais tratamentos. As mudas de coqueiro inoculadas com o B. cocophilus apresentaram aumento nas atividades das enzimas peroxidases, quitinase e β-1,3-glucanases, quando comparadas com a testemunha (mudas não inoculadas). Os isolados B41, P14, T41 e T54 apresentaram-se como potenciais agentes de controle biológico do B. cocophilus.Palavras-chave: anel vermelho, antagonismo, nematoid. BIOLOGIC CONTROL OF Bursaphelenchus cocophilus WITH RHIZOBACTERIA AND Trichoderma isolates  ABSTRACT:The purpose of this study was to evaluate the potential of rhizobacteria Pseudomonas spp. and Bacillus spp. and Trichoderma spp. isolates on the biological control of the nematode Bursaphelenchus cocophilus. The potential biological control isolates (48 rhizobacteria and 27 Trichoderma spp.) were characterized biochemically. The biological control experiments were carried out "in vitro" and "in vivo", and in the later one, the mortality rate of the nematodes and the pathogenesis related enzymes were evaluated. Rhizobacterial isolates B14 and P41 provided a high nematode mortality rate (69% and 56%, respectively) and both were proteolytic and phosphate solubilizers. In the "in vivo" experiment, rhizobacterial isolates B14, B23 and P23 tested the highest mortality rates of B. cocophilus than the isolates of Trichoderma spp. and of the control as coconut saplings challenged with B. cocophilus showed indices higher in enzyme activities, peroxidases, chitinase and β-1,3-glucanases when compared to witness (seedling not inoculated). The isolates B41, P14, T41 and T54 were presented as potential biological control agents of B. cocophilus.Keywords: red ring, antagonism, nematode. DOI:

Energy and water dynamics are crucial for citrus development in the Eastern Amazon. This study aimed to determine the energy balance, water demand, and crop coefficient of acid lime in the northeast region of Pará. A micrometeorological tower was installed in the center of the experimental area to monitor meteorological variables between October 2020 and December 2021. The energy balance and water demand were obtained by the Bowen ratio method. Kc was determined by the ratio between crop and reference evapotranspiration. The results obtained indicate that 63% of the available energy was used by latent heat in the rainiest period, while 60% was used during the less rainy period. Sensible heat used 32% and 34% during the most and least rainy periods, respectively. Soil heat presented a low variation, with an average of 5% for the entire period. Water consumption of the acid lime during the experiment was 1599 mm, with a daily mean of 3.70 mm day−1, while the mean value of Kc was 1.4. These results allow for the design of adequate water supply protocols for the crop in the main citrus pole in the Amazon region.

IntroduçãoVárias espécies arbóreas têm sido utilizadas na recuperação de áreas degradadas, devido ao seu rápido crescimento e rusticidade (LIMA, 2004), principalmente aquelas de rápido crescimento, que são excelentes para plantios mistos e recomposição de áreas degradadas (LORENZI, 2002).Dentre estas, encontra-se o Jucá (Caesalpinia ferrea Mart. ex Tul. var. ferrea), espécie pertencente à família Fabaceae (Leguminosae), uma planta arbórea, de ampla dispersão e baixa densidade populacional, formando copa arredondada, fechada e densa (LORENZI, 2002). O jucá tem grande potencial medicinal e ornamental e sua madeira de alta densidade é utilizada na construção civil e na carpintaria (LORENZI, 2000; MAIA, 2004).Porém, esta espécie está sujeita ao ataque de vários fitopatógenos, dentre os quais os fungos são os mais ativos, apresentando maior habilidade em penetrar e se alojar mais facilmente nos tecidos vegetais (MACHADO, 1988), como é o caso do fungo Lasiodiplodia sp. (Pat.) Griffon Maublque, que é polífago, sendo capaz de infectar, isoladamente ou em associação com outros patógenos, mais de 500 espécies vegetais (FREIRE;CARDOSO, 2003).A qualidade e a intensidade de luz são fatores que podem afetar a germinação de conídios, a taxa de crescimento vegetativo e a indução de formação de estruturas reprodutivas. Para a maioria dos organismos, a luminosidade é um fator ambiental que regula o desenvolvimento e os processos de metabolismo (SOUZA et al., 2015). A temperatura é outro fator que exerce influência no crescimento, esporulação e germinação dos fungos (TEIXEIRA et al., 2001).Os meios de cultura tem função importante no crescimento micelial de fungos fitopatogênicos. Em geral, estes fungos utilizam para o seu crescimento e desenvolvimento várias

Fusariosis (Fusarium solani f.sp. piperis) is one of the most damaging diseases of black pepper crop in the Amazon zone and the application of organic materials to the soil may be an alternative to control this disease. Leaf residues of Piper aduncum were evaluated before and after the extraction of essential oil, as additives to the soil inoculated with Fusarium solani, in the survival and morphophysiological behavior of black pepper seedlings. The experiments were conducted at Embrapa Eastern Amazônia, Belém, PA. The effects of the by-products of the distillation of the essential oil of P. aduncum on the survival to fusariosis in black pepper seedlings and the effect of dry and crushed leaves of P. aduncum, preincubated in the soil, in the incidence of fusariosis and in the behavior of black pepper seedlings were evaluated. The addition of solid residues from P. aduncum oil extraction to the soil increased the survival of seedlings by 80% and in the presence of dry and crushed leaves of P. aduncum the survival was 83%. The net photosynthesis of the seedlings increased in the presence of residues of P. aduncum. The residues from the extraction of the essential oil of P. aduncum and its dry and crushed leaves, without oil extraction, have potential for use in the control of fusariosis in black pepper plants.