Eryngium amethystinum (amethyst sea holly) is a herbaceous plant commonly grown as an ornamental perennial in U.S.D.A. hardiness zones 3 to 8. The plant thrives in dry areas with infertile soils and the flowers are often used in dried floral arrangements. Canna spp. (Canna), soft perennials (U.S.D.A. zone 9 and above), are becoming popular flowering plants because of their bright flowers and spectacular foliage. There are a variety of species that fall under the heading Canna spp., of which the most popular are C. glauca, C. indica, C. edulis, and C. iridiflora. Hybrids of Aquilegia (garden columbine), a hardy perennial (U.S.D.A. zones 3 to 9), flower in late spring through early summer. The genus is made up of a wide variety of cultivars. E. amethystinum exhibiting severe mosaic, yellowing, and stunting, along with Canna plants exhibiting severe stunting, chlorotic and distorted foliage, and mosaic, and garden columbine plants exhibiting stunting, leaf curl, chlorosis, and mosaic, collected from commercial plantings throughout the central Ohio area, were analyzed for the presence of virus infection with viral-associated, double-stranded RNA (dsRNA) analysis. dsRNA analysis resulted in a banding profile typical of that seen with members of the cucumovirus family of plant viruses. Plants positive for cucumovurus-like dsRNA were tested with a direct antibody sandwich enzyme-linked immunosorbent assay (ELISA). ELISA results confirmed the presence of cucumber mosaic virus (CMV) in all symptomatic plants tested. No evidence of dsRNA or CMV was found in any of the asymptomatic plants tested. Because all of these hosts are common in the perennial garden, they could serve as a reservoir host of CMV for other plants in the garden. This is the first report of CMV in E. amethystinum, Canna spp., and Aquilegia hybrids in Ohio.

Double petunia plants expressing virus-like symptoms were collected in greenhouses and garden centers throughout Ohio in Spring 1997 and 1998 in an effort to determine the frequency and distribution of petunia viruses present in the state. Direct antibody-sandwich and indirect enzyme-linked immunosorbent assay (ELISA) were conducted with commercial antisera made against 13 viruses, a potyvirus kit capable of detecting 80 different potyviruses, and our antiserum raised against a tobamo-like virus inducing severe mosaic in double petunia. Viral-associated double-stranded ribonucleic acid (dsRNA) analysis and light microscopy for detection of inclusion bodies were also carried out. ELISA, dsRNA analysis, and light microscopy revealed the presence of tobacco mosaic tobamovirus, an unknown tobamo-like petunia virus, tomato ringspot nepovirus, tobacco streak ilarvirus, and tobacco ringspot nepovirus. Tomato aspermy cucumovirus, tomato spotted wilt tospovirus, impatiens necrotic spot tospovirus, alfalfa mosaic virus, cucumber mosaic cucumovirus, potato virus X potexvirus, and chrysanthemum B carlavirus were not detected. No potyviruses were identified. A number of plants with virus-like symptoms tested negative for all viruses.

Coffee rust is the most important disease of the crop, the severity of leaf damage caused by the pathogen causes leaf abscission and significantly affects the reduction of yields. This investigation was carried out with the objective of comparing the visual method with a digital one, in the quantification of the percentage of severity of the rust in different sizes of leaves. The quantifications of the disease were carried out at the University Clinic for Agricultural Diagnostics at Oriente University. To carry out the experiment, 360 leaves injured with rust were collected from Catuaí Rojo plantations and divided into three groups, categorized according to leaf area into large, medium and small, each group was represented by 120 leaves, initially evaluated by the visual method by two observers with the help of the diagrammatic scale and later with the digital method by analyzing images with the ImageJ® program. The randomized block design was used with a 2x3 factorial arrangement with ten repetitions per experimental unit. The data were processed by analysis of variance. It was found that the severity percentage did not present statistical differences for the digital methodology when the size of the sheets was changed; while, for the visual methodology, therewas an influence of the size of the leaves, observing that the estimated severity increased as the size of the leaves decreased. The digital method is a reliable alternative for the quantification of the severity of attack by coffee rust.

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Con el objetivo de identificar hongos asociados a semillas de moringa en el estado Monagas, Venezuela, se condujo esta investigación con material obtenido de cuatro localidades, Caicara de Maturín, municipio Cedeño y bancos de semilla de los sectores Las Avenidas, Brisas del Aeropuerto y Terrenos de Guarapiche, del municipio Maturín. Por procedencia, las semillas fueron caracterizadas en aspectos físicos e intrínsecos y seleccionadas aleatoriamente para diagnóstico 250 unidades; 125 sembradas directamente en cámaras húmedas, sin desinfección, en capsulas de Petri con papel absorbente, humedecido con agua destilada estéril y 125 desinfectadas en solución al 10 % v/v de hipoclorito de sodio 3.5 % durante dos minutos, ambos grupos de semillas, incubadas en cámaras bajo condiciones de laboratorio. Se empleó el diseño en bloques al azar con arreglo factorial 4 x 2, con cinco repeticiones y cinco cápsulas por unidad experimental. Se cuantificó la frecuencia de aparición de cada colonia fúngica y el porcentaje de germinación de las semillas, a los 5, 10 y 15 días luego de la siembra. Los resultados fueron analizados e interpretados por estadística no paramétrica. Se detectó Aspergillus sp., Rhizopus sp., Fusarium sp., Penicillium sp., Monilia sp. y Trichoderma sp., siendo Aspergillus sp., el aislamiento fúngico más frecuente. Semillas recién cosechadas presentaron con más frecuencia Fusarium; mientras que en semillas almacenadas se observó los géneros Aspergillus, Rhizopus y Penicillium. Aspergillus y Rhizopus causaron niveles de infestación del 100 % en semillas sin ningún poder germinativo. Trichoderma sp., solo se detectó en el tratamiento sin desinfección de las semillas, con bajo porcentaje de detección.