Coffee Science
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3355
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Item Manganese and fluorine suppress bacterial blight on coffee seedlings grown in a nutrient solution(Editora UFLA, 2021) Velloso, Jeanny Alice; Pozza, Edson Ampelio; Pozza, Adelia Aziz Alexandre; Silva, Humberson Rocha; Pérez, Cristian David Plaza; Souza, José Otávio Gusmão deThe use of manganese (Mn) and fluorine (F) in the management of bacterial blight were evaluated in coffee seedlings grown in a nutrient solution. The experiment was carried out with the cultivar Catuaí Vermelho IAC 99. The treatments consisted of the combination of five doses of Mn with five of F, applied via leaf, using Mn sulfate and sodium fluoride, in a 5x5 factorial scheme. The plants were inoculated with bacterial suspension seven days after foliar application of F and Mn doses. The incidence and severity assessments were performed at an interval of 24 hours for 10 days. Photosynthetic activity was assessed using the infrared gas analyzer. Stomatal conductance, photosynthesis, transpiration, PAR radiation and internal CO2 were ana lyzed. The chlorophyll content was calculated indirectly. The leaf analysis was performed by digestion in HNO3 to determine the levels of Mn. Variables such as Area Under Incidence Disease Progress (AUIDP), Area Under Severity Disease Progress (AUSDP), chlorophyll a, b, and total concentrations and photosynthesis were submitted to the Shapiro-Wilk test. The treatment means were subjected to linear regression analysis. Data were analyzed using software R. There was a significant interaction (P <0.05) between the concentrations of Mn and F for the AUIDP and (AUSDP). Doses between 0.7 and 1.4 g L-1 of Mn combined with doses of 0.10 to 0.12 g L-1 of F were more effective in suppressing the bacterial blight, after analysis for both variables. The increase in Mn concentrations in leaves reduced liquid photosynthesis. The interaction between Mn and F suppressed the bacterial blight intensity of the coffee plants in nutrient solution.Item Nitrogênio e potássio na intensidade da mancha aureolada do cafeeiro em solução nutritiva(Editora UFLA, 2017-01) Pérez, Cristian David Plaza; Pozza, Edson Ampélio; Pozza, Adélia Aziz Alexandre; Freitas, Aurivan Soares; Silva, Marília Goulart daA nutrição equilibrada pode auxiliar no controle de doenças do cafeeiro. Assim, objetivou-se avaliar o efeito da adubação nitrogenada e potássica na intensidade da mancha aureolada do cafeeiro, em câmara de crescimento. Utilizou-se a cultivar Mundo Novo 376/4, suscetível à doença. Os tratamentos consistiram de cinco doses de N (3, 7, 11, 15 e 19 mmol L -1 ) combinadas com cinco doses de K (3, 5, 7, 9 e 11 mmol L -1 ), em esquema fatorial 5 x 5, totalizando 25 tratamentos e três repetições compostas por duas mudas em solução nutritiva. O delineamento experimental foi o inteiramente casualizado. Avaliou-se a incidência e a severidade da doença. A área abaixo da curva de progresso da incidência (AACPDI) e da severidade (AACPDS) foi calculada. Observou-se a maior incidência da doença (97,2%) na combinação das maiores doses de N e K. Houve diferença significativa apenas para o N na AACPDS, massa da planta seca e clorofilas a, b e total. A menor AACPDS (7,79) foi obtida com a dose 13,34 mmol L -1 de N. Houve correlação significativa e positiva para as clorofilas a, b e total com o N e a AACPS.