Effect of basil [Ocimuin Basilicum L.] essential oil on gray mold control and postharvest quality of strawberry [cv. Selva]

Essential oils are complex volatile compounds produced in different plant parts, which are known to have various functions in plants. The objective of the present study is investigation of the effect of Basil [L. Ocimum basilicum L.] essential oil on gray mold control and postharvest quality of strawberry. This experiment was carried out In vitro and In vivo conditions. In In vitro condition Basil essential oil was used at 250, 500, 750 and 1000 microL.L[-1] concentrations with "Paper Disk Method" and "Solution Method". In second stage Basil essential oil applied at 60, 250, 500 and 1000 microL.L[-1] concentrations with "Paper Disk Method" on strawberry fruits. Results of In vitro experiment showed that Basil essential oil at all applied concentrations inhibited Botrytis cinerea growth completely. The results of In vivo experiment showed that basil essential oil at applied concentrations inhibited B. cinerea growth on strawberry fruits completely in comparison to controls. Also basil essential oil at 60 and 250 microL.L[-1] concentrations showed positive effects on some fruit quality characteristics e.g. color, titrable acidity, total soluble solid, Vitamin C and firmness. Therefore treated fruits with basil essential oil at low concentration had higher TA, TSS, Vitamin C, firmness and color values compared to control fruits whilst high concentrations of basil essential oil [500 and 1000 microL.L[-1]] induced burning sepal and led to toxic signs on fruit surface. All applied concentrations of basil essential oil affected fruit flavor especially 1000microL.L[-1] reduced fruit firmness and Vitamin C content It can be concluded that basil essential oil due to higher antifungal properties, acts as an alternative to artificial fungicides in controlling of fungal diseases but more research is needed to identify the proper formulation

Escala diagramática para avaliação da severidade da mancha-de-micosferela em morangueiro / Diagramatic scale to evaluate the mycosphaerella blight severity in strawberry

Uma escala diagramática com cinco níveis: 0,11; 0,51; 2,4; 10,2 e 34,9 por cento foi desenvolvida e validada para quantificar a severidade da mancha-de-micosferela do morangueiro, causado por Mycosphaerella fragariae (Tul.) Lin. A escala considerou os limites de severidade mínima e máxima da doença observados no campo e os níveis intermediários seguiram incrementos logarítmicos, obedecendo-se à "Lei do estímulo de Weber-Fechner". Inicialmente, a estimativa da severidade foi feita sem auxílio da escala em 30 folíolos com diferentes níveis de severidade, por sete indivíduos, sem experiência na avaliação da mancha-de-micosferela do morangueiro . Em seguida, os mesmos avaliadores utilizaram a escala diagramática proposta. As avaliações com a escala diagramática foram mais precisas e acuradas nas estimativas de todos os avaliadores, não ocorrendo erro sistemático na superestimativa ou subestimativa da doença entre estes. A escala diagramática proposta foi considerada adequada para estimar a severidade de mancha-de-micosferela em morangueiro.

Detección mediante PCR-RFLP de Fusarium oxysporum f.sp. fragariae agente causal de fusariosis en frutilla / Detection by PCR-RFLP of Fusarium oxysporum f. sp. fragariae causal agent of fusariosis in strawberry

La frutilla es una de las frutas de importante crecimiento económico tanto en Chile como a nivel Mundial. Desde hace varios años su producción ha experimentado pérdidas económicas, principalmente a causa de las enfermedades producidas por Fusarium oxysporum f.sp. fragariae (Fof). Este patógeno, se ha propagado rápidamente por casi todo el mundo debido a su difícil diagnóstico y actualmente la única manera de detectarlo es mediante test de patogenicidad, técnica laboriosa que requiere de bastante tiempo y material, lo que dificulta su detección oportuna. Debido a que el diagnóstico genético y las técnicas moleculares son metodologías rápidas y altamente eficaces, el objetivo de este trabajo fue diseñar un método para detectar a Fof, con el fin de controlar y certificar el ingreso o salida del país de este patógeno. Para esto se amplificó el gen ®Factor de Elongación 1- α¼ (EF1- α), en 25 cepas de F. oxysporum aisladas desde diversas localidades de la VIII región y R. Metropolitana, 4 cepas otorgadas por el laboratorio Nacional del Servicio Agrícola y Ganadero (SAG), y 4 cepas patogénicas controles importadas desde ATCC, EE.UU. Posteriormente por digestión con endonucleasas MseI y MspI se logró diferenciar las cepas de Fusarium oxysporum f.sp. fragariae de las respectivas cepas no patogénicas de este hongo. Estos resultados fueron confirmados mediante electroforesis en geles de poliacrilamida denaturante, RFLP con dos endonucleasas y parcialmente mediante secuenciación del producto amplificado de Fof, revelándose de esta manera la eficacia de esta metodología.

The strawberry is one of the fruits with important economic growth both in Chile, as on a world-wide basis.For several years, the fruits production has suffered economic losses principally due to the causes of Fusarium oxysporum f.sp. fragariae (Fof) produced diseases.Thispathogen has widely propagated around the world, due to it is complex diagnosis.Actually, the only way to detect them is buy using a pathogenic test, which is a laborious technique that requires a long time and complex materials to effect, which makes an opportune detection difficult. Since genetic diagnosis and molecular techniques are fast and highly efficient methods, the aim of this workis to elaborate a method to detect Fof, with the aim of controlling and certifying the countries of import or exportof these pathogens. To carry this out, the genetic of Elongation Factor 1- á (EF1- á), in 25 strains of F. oxysporum was separated from diverse areas in the 8th Region and the Metropolitan Region. Plus 4 strains kindly donated by the National Laboratory of Agriculture and Livestock (SAG) and 4 pathogenic control strains imported from ATCC, USA.After digestion with endonucleases MseI y MspI it was possible to differentiate Fof and a strain of Fusarium oxysporum f.sp. lycopersicis from their respective strains of non pathogenic F. oxysporum.These results were confirmed by electrophoresis in denaturant poliacrylamide gels, RFLP with twoendonucleases and partially by secuentiation of the amplified product of the Fof revealing in this form the efficiency of the methodology employed.