Soil solarization for weed control in carrot.

Soil solarization is a technique used for weed and plant disease control in regions with high levels of solar radiation. The effect of solarization (0, 3, 6, and 9 weeks) upon weed populations,carrot (Daucus carota L. cv. Brasília) yield and nematode infestation in carrot roots was studied in São Luís (2o35' S; 44o10' W), MA, Brazil, using transparent polyethylene films (100 and 150 mm of thickness). The maximum temperature at 5 cm of depth was about 10oC warmer in solarized soil than in control plots. In the study 20 weed types were recorded. Solarization reduced weed biomass and density in about 50% of weed species, including Cyperus spp., Chamaecrista nictans var. paraguariensis(Chod & Hassl.) Irwin & Barneby,Marsypianthes chamaedrys (Vahl) O. Kuntze, Mitracarpus sp.,Mollugo verticillata L., Sebastiania corniculata M. Arg., and Spigelia anthelmia L. Approximately 40% of species in the weed flora were not affected by soil mulching. Furthermore, seed germination of Commelina benghalensis L. was increased by soil solarization. Marketable yield of carrots was greater in solarized soil than in the unsolarized one. It was concluded that solarization for nine weeks increases carrot yield and is effective for controlling more than half of the weed species recorded. Mulching was not effective for controlling root-knot nematodes in carrot

ÓLEO ESSENCIAL DE ERVA-CIDREIRA SOBRE FITOPATÓGENOS DE ESPÉCIES FLORESTAIS E AGRÍCOLAS

Belonging to Verbenaceae, Lippia alba (Mill) N. E. Brown family's used in folk medicine because its analgesic properties, calming and spasmolytic. In this work, we tried to evaluate the essential oil effect on the mycelial growth of Fusarium spp. obtained from Anacardium occidentale L. (cashew); Zea mays L. (corn); Capsicum annuum L. (pepper); Couratari oblongifolia Ducke & R. Knuth (tauari) and Rhizoctonia solani obtained of the species Glycine max L. (soy bean). In the bioassay, the previously filtered oil was added in PDA (Potato-Dextrose-Agar) medium, homogenized and poured into Petri dishes. Then, disks containing fungal structures were deposited, centrally, on the PDA plates and the oil at their respective concentrations. The control treatment consisted of plates with culture medium without the presence of oil. The data were obtained by measuring the diameter of the fungal colonies for five days. All concentrations reduced the mycelial growth of phytopathogens in relation to the control, presenting an average inhibition percentage of 88.5%. For the isolates of Fusarium spp. of cashew and pepper, as well as Rhizoctonia solani isolated from soy bean, the oil presented fungicidal effect; suggesting studies, in vivo, to verify it’s fungitoxic effect, and chemical analyzes for investigation and isolation of the active compounds of the species.KEYWORDS: Alternative control, Fungicidal effect, Reduced growth.Pertenencia a la familia Verbenaceae, Lippia alba (Mill) N. E. Brown es ampliamente utilizada en la medicina popular debido a sus propiedades analgésicas, calmantes y espasmolíticas. En este trabajo, se buscó evaluar el efecto aceite esencial de esa especie sobre el crecimiento micelial de los aislados de Fusarium spp. obtenidos de Anacardium occidentale L. (cajú); Zea mays L. (maíz); Capsicum annuum L. (chile); Couratari oblongifolia Ducke & R. Knuth (tauari) y Rhizoctonia solani obtenida de la especie Glycine max L. (soja). En el bioensayo, el aceite previamente filtrado fue agregado en medio BDA (Batata-Dextrosa-Agar), homogeneizado y vertido en placas de Petri. A continuación, los discos que contenían estructuras fúngicas se depositaron centralmente en las placas con BDA y el aceite en sus respectivas concentraciones. El tratamiento control consistió en placas con medio de cultivo sin la presencia del aceite. Los datos fueron obtenidos midiendo el diámetro de las colonias fúngicas, durante cinco días. Todas las concentraciones reducen el crecimiento del micelio de patógenos de plantas en comparación con el control, con un porcentaje de inhibición media de 88,5%. Para los aislados de Fusarium spp. del cajú y del chile, así como Rhizoctonia solani aislado de la soja, el aceite presentó efecto fungicida; sugiriendo estudios, in vivo, para constatacíon de su efecto fungitóxico, y análisis químicos para investigación y aislamiento de los compuestos activos de la especie.PALABRAS CLAVE: Control alternativo, Efecto fungicida, reducción del crecimiento.Pertencente à família Verbenaceae, Lippia alba (Mill) N. E. Brown é amplamente utilizada na medicina popular devido suas propriedades analgésicas, calmantes e espasmolíticas. Neste trabalho, buscou-se avaliar o efeito do óleo essencial dessa espécie sobre o crescimento micelial de isolados de Fusarium spp. obtidos de Anacardium occidentale L. (caju); Zea mays L. (milho); Capsicum annuum L. (pimentão); Couratari oblongifolia Ducke & R. Knuth (tauari) e Rhizoctonia solani obtido da espécie Glycine max L. (soja). No bioensaio, o óleo previamente filtrado foi adicionado em meio BDA (Batata-Dextrose-Ágar), homogeneizado e vertido em placas de Petri. Em seguida, discos contendo estruturas fúngicas foram depositados, centralmente, nas placas com BDA e o óleo em suas respectivas concentrações. O tratamento controle consistiu em placas com meio de cultura sem a presença do óleo. Os dados foram obtidos medindo o diâmetro das colônias fúngicas, durante cinco dias. Todas as concentrações reduziram o crescimento micelial dos fitopatógenos em relação à testemunha, apresentando um percentual de inibição médio de 88,5%. Para os isolados de Fusarium spp. do caju e do pimentão, bem como Rhizoctonia solani isolado da soja, o óleo apresentou efeito fungicida; sugerindo estudos, in vivo, para constatação de seu efeito fungitóxico, e análises químicas para investigação e isolamento dos compostos ativos da espécie.PALAVRAS-CHAVE: Controle alternativo, Efeito fungicida, Redução do crescimento

ANÁLISIS FITOQUÍMICO Y ACTIVIDAD ANTIFÚNGICA DEL EXTRACTO ETANÓLICO DEL RESIDUO DE HOJAS Y MADERA DE MACACAPORANGA

Os óleos e extratos vegetais têm se destacado como alternativa promissora para o controle de fitopatógenos e, os resíduos sólidos provenientes da hidrodestilação de óleos essenciais também podem ser testados visando a obtenção de moléculas bioativas para esse fim. Objetivou-se avaliar a atividade antifúngica do extrato etanólico residual das folhas e madeira de Aniba parviflora (Meins.) Mez (macacaporanga) sobre o fungo Alternaria sp. provenientes de folhas de eucalipto. Os extratos foram obtidos via Soxhlet, após a extração do óleo essencial, e realizada a triagem fitoquímica através de cromatografia em camada delgada (CCD). No ensaio biológico, os extratos foram testados nas concentrações de 10%, 20%, 30%, 40% e 50%, sendo solubilizados em água, adicionados em meio batata-dextrose-água (BDA) e vertidos para placas de Petri. Após solidificação do meio, depositou-se, centralmente, um disco de BDA contendo as estruturas do fungo. O tratamento controle consistiu da deposição de Alternaria em BDA, sem a presença dos extratos. Avaliou-se, diariamente, medindo-se o diâmetro médio das colônias, calculando-se a porcentagem de inibição do crescimento (PIC). O delineamento foi inteiramente casualizado, em esquema fatorial, com quatro repetições. Verificou-se a presença de terpenóides e flavonoides nos extratos das folhas e madeira. O extrato da madeira e das folhas proporcionaram PIC de 30,3% e de 21,4%, respectivamente. As concentrações de 40% e 50% ocasionaram as maiores reduções no crescimento do fungo. Ambos os extratos apresentaram efeito fungistático nas concentrações testadas, sendo o da madeira mais promissor na redução do crescimento micelial do fungo.PALAVRAS-CHAVE: Borra vegetal, Controle alternativo, Fungo.Plant oils and extracts have emerged as a promising alternative for the control of phytopathogens, and the solid residue from the hydrodistillation of essential oils can also be tested in order to obtain bioactive molecules for this purpose. The objective of the study was evaluate the antifungal activity of the residual ethanolic extract of leaves and macacaporanga wood on the fungus Alternaria sp. from eucalyptus leaves. The extracts were obtained by Soxhlet, after extraction of the essential oil, and the phytochemical screening was performed by thin layer chromatography. In the biological assay, the extracts were tested at the concentrations of 10%, 20%, 30%, 40% and 50%, being solubilized in water, added in potato-dextrose-water (PDA) medium and poured into Petri dishes. After solidification of the medium, a PDA disc containing the structures of the fungus was deposited centrally. The control treatment consisted of the deposition of Alternaria in PDA, without the presence of extracts. The mean diameter of the colonies was measured daily by calculating the percentage of growth inhibition. The design was completely randomized, in a factorial scheme, with four replications. The presence of terpenoids and flavonoids in leaves and wood extracts was verified. The extract of the wood and leaves provided ICPs of 30.3% and 21.4%, respectively. Concentrations of 40% and 50% caused the greatest reductions in fungus growth. Both extracts presented a fungistatic effect in the tested concentrations, being the one of the wood more promising in the reduction of the mycelial growth of the fungus.KEYWORDS: Alternative control, Fungus, Vegetable waste.Los aceites y extractos vegetales se han destacada como una alternativa prometedora para el control de fitopatógenos y los residuos sólidos provenientes de la hidrodestilación de aceites esenciales también pueden ser probados para la obtención de moléculas bioactivas para ese fin. Se objetivó evaluar la actividad antifúngica del extracto etanólico residual de las hojas y madera de Aniba parviflora (Meins.) Mez (macacaporanga) sobre el hongo Alternaria sp. provenientes de hojas de eucalipto. Los extractos fueron obtenidos vía Soxhlet, después de la extracción del aceite esencial, y realizada la clasificación fitoquímica a través de cromatografía en capa delgada (CCD). En el ensayo biológico, los extractos se probaron en las concentraciones del 10%, 20%, 30%, 40% y 50%, siendo solubilizados en agua, añadidos en medio patata-dextrosa-agua (PDA) y vertidos para placas de Petri. Después de la solidificación del medio, se depositó, centralmente, un disco de PDA conteniendo las estructuras del hongo. El tratamiento control consistió de la deposición de Alternaria en BDA, sin la presencia de los extractos. Se evaluó, diariamente, midiendo el diámetro medio de las colonias, calculándose el porcentaje de inhibición del crecimiento (PIC). El delineamiento fue completamente casualizado, en esquema factorial, con cuatro repeticiones. Se verificó la presencia de terpeloides y flavonoides en los extractos de las hojas y la madera. El extracto de la madera y de las hojas proporcionó PIC del 30,3% y del 21,4%, respectivamente. Las concentraciones de 40% y 50% ocasionaron las mayores reducciones en el crecimiento del hongo. Ambos extractos presentaron efecto fungistático en las concentraciones probadas, siendo el de la madera más prometedor en la reducción del crecimiento micelial del hongo.PALABRAS CLAVE: Control alternativo, Gomas vegetales, Hongo

QUALIDADE FISIOLÓGICA E SANITÁRIA DE SEMENTES DE PIMENTÃO COMERCIALIZADAS EM SANTARÉM, PARÁ

The physiological and sanitary quality of seeds is one of the most important aspects to achieve crop success. In this sense, the objective of this work was to evaluate the physiological and sanitary quality of seven cultivars of pepper (Capsicum annuum L.) commercialized in Santarém, Pará. The seeds were distributed equidistantly in gerbox® plastic boxes containing sterilized and moistened filter paper and maintained at ± 25 ° C for 14 days with 12h photoperiod. Germination, number of normal and abnormal seedlings at seven and 14 days, germination speed index (IVG) and fungi incidence on the seeds were evaluated. The experimental design was completely randomized, with four replicates, 50 seeds per replicate, making a total of 1400 seeds evaluated. All the lots of the evaluated pepper cultivars exhibited low vigor, considering the low percentage of normal seedlings resulting. The lots of the cultivars All Big, Yellow SF 134, Red Square and Ruby Giant presented germination within the standards informed by the manufacturers. In the seeds of Yellow SF 134 and Itapuã 501 100% of fungal incidence was observed, being identified the genera Aspergillus, Fusarium, Penicillium and Rhizopus. Itapuã 501 presented the worst physiological and sanitary performance among the lots of the evaluated cultivars. Considering the low percentage of normal seedlings resulting, the plots of the pepper cultivars evaluated in this work could compromise the initial planting stand.KEYWORDS: Capsicum annuum, Germination, Seed pathology, Vigor.La calidad fisiológica y sanitaria de las semillas es uno de los aspectos más importantes para alcanzar el éxito del cultivo. En ese sentido, el trabajo objetivó evaluar la calidad fisiológica y sanitaria de siete cultivares de pimiento (Capsicum annuum L.) comercializadas en Santarém, Pará. Las semillas fueron distribuidas equidistantemente en cajas plásticas del tipo gerbox® conteniendo papel filtro esterilizado y humedecido, y mantenidas a ± 25ºC durante 14 días con fotoperíodo de 12h. Se evaluaron la germinación, el número de plántulas normales y anormales a los siete y 14 días, índice de velocidad de germinación (IVG) e incidencia de hongos sobre las semillas. El delineamiento experimental fue completamente casualizado, con cuatro repeticiones, siendo 50 semillas por repetición, totalizando un total de 1400 semillas evaluadas. Todos los lotes de los cultivares de pimiento evaluados exhibieron bajo vigor, considerando el bajo porcentaje de plántulas normales resultantes. Los lotes de los cultivares All Big, Amarillo SF 134, Cuadrado Rojo y Rubí Gigante presentaron germinación dentro de los estándares informados por los fabricantes. En las semillas de Amarillo SF 134 e Itapuã 501 se observó un 100% de incidencia fúngica, siendo identificados los géneros Aspergillus, Fusarium, Penicillium y Rhizopus. Itapuã 501 presentó el peor desempeño fisiológico y sanitario entre los lotes de los cultivares evaluados. Se consideró el bajo porcentaje de plántulas normales resultantes, los lotes de los cultivares de pimiento evaluados en ese trabajo podrían comprometer el stand inicial de la siembra.PALABRAS CLAVE: Capsicum annuum, Germinación, Patología de semillas, Vigor.A qualidade das sementes é um dos aspectos mais importantes para se alcançar o sucesso da lavoura. Nesse sentindo, objetivou-se com este trabalho avaliar a qualidade fisiológica e sanitária de sete cultivares de pimentão (Capsicum annuum L.) comercializadas em Santarém, Pará. As sementes foram distribuídas, equidistantemente, em caixas plásticas do tipo gerbox® contendo papel filtro esterilizado e umedecido, e mantidas a ± 25ºC durante 14 dias com fotoperíodo de 12h. Foram avaliados a germinação, o número de plântulas normais e anormais aos sete e 14 dias, índice de velocidade de germinação (IVG) e incidência de fungos sobre as sementes. O delineamento experimental foi inteiramente casualizado, com quatro repetições, sendo 50 sementes por repetição, perfazendo um total de 1400 sementes avaliadas. Todos os lotes das cultivares de pimentão avaliados exibiram baixo vigor, considerando-se a baixa porcentagem de plântulas normais resultantes. Os lotes das cultivares All Big, Amarelo SF 134, Quadrado Vermelho e Rubi Gigante apresentaram germinação dentro dos padrões informados pelos fabricantes. Nas sementes de Amarelo SF 134 e Itapuã 501 observou-se 100% de incidência fúngica, sendo identificados os gêneros Aspergillus, Fusarium, Penicillium e Rhizopus. Itapuã 501 apresentou o pior desempenho fisiológico e sanitário dentre os lotes das cultivares avaliadas. Considerando-se a baixa porcentagem de plântulas normais resultantes, os lotes das cultivares de pimentão avaliados nesse trabalho poderiam comprometer o estande inicial do plantio. PALAVRAS-CHAVE: Capsicum annuum, Germinação, Patologia de sementes, Vigor

Bioactivity of Ethanolic Extracts of <i>Dipteryx punctata</i> on <i>Colletotrichum musae</i>

Bioactivity with antifungal properties has already been reported for some species of the genus Dipteryx. However, little is known about Dipteryx punctata. We evaluated the antifungal activity, in vitro and in vivo, of extracts of leaves, branches and fruits of D. punctata on Colletotrichum musae, the causal agent of anthracnose in bananas. The extracts and the coumarin standard were tested in vitro, at concentrations of 10%, 20%, 30%, 40%, and 50% (w/v), added in potato-dextrose-agar (PDA) medium. The experimental design was completely randomized, factorial design, with four replications. The average diameter of the fungal colonies was evaluated daily for eight days, and at the end, the percentage of inhibition and growth rates were calculated. For in vivo tests, the products were tested at concentrations of 40% and 50%, in preventive and curative applications. In these tests, three medium disks (5 mm) containing phytopathogen structures were deposited at opposite points of the fruits, and remained in a humid chamber for 48 h. Anthracnose lesions were measured at an interval of two days, up to eight days after fungus inoculation. In the in vitro essay, the extracts of the branches and residues of the fruits of D. punctata and the coumarin pattern caused the biggest reductions in the average diameter of the colonies of the phytopathogen. D. punctata and coumarin extracts were promising in terms of in vivo antifungal activity, especially in preventive applications, being an important source of investigation for the formulation of natural products as sustainable phytosanitary measures

Bioactivity of Ethanolic Extracts of Dipteryx punctata on Colletotrichum musae

Bioactivity with antifungal properties has already been reported for some species of the genus Dipteryx. However, little is known about Dipteryx punctata. We evaluated the antifungal activity, in vitro and in vivo, of extracts of leaves, branches and fruits of D. punctata on Colletotrichum&nbsp;musae, the causal agent of anthracnose in bananas. The extracts and the coumarin standard were tested in vitro, at concentrations of 10%, 20%, 30%, 40%, and 50% (w/v), added in potato-dextrose-agar (PDA) medium. The experimental design was completely randomized, factorial design, with four replications. The average diameter of the fungal colonies was evaluated daily for eight days, and at the end, the percentage of inhibition and growth rates were calculated. For in vivo tests, the products were tested at concentrations of 40% and 50%, in preventive and curative applications. In these tests, three medium disks (5 mm) containing phytopathogen structures were deposited at opposite points of the fruits, and remained in a humid chamber for 48 h. Anthracnose lesions were measured at an interval of two days, up to eight days after fungus inoculation. In the in vitro essay, the extracts of the branches and residues of the fruits of D. punctata and the coumarin pattern caused the biggest reductions in the average diameter of the colonies of the phytopathogen. D. punctata and coumarin extracts were promising in terms of in vivo antifungal activity, especially in preventive applications, being an important source of investigation for the formulation of natural products as sustainable phytosanitary measures