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Particular importance is given to the leafhoppers belonging to the sub-family Typhlocybinae- because they are the most numerous within the family Cicadellidae, and many of them are potential vectors of serious phytoplasmatic diseases. The presence of yellowish blotches and numerous micro-leafhopper on soursop (Annona muricata L.) leaves led to the conduction of this work to identify the leafhoppers occurring on soursop in the municipality Diez de Octubre, province of Havana. Leafhoppers on plants growing into private yards were sampled from April to June 2015. The collected insects were cleared, mounted on slides and observed under a stereomicroscope Stemi 4 and a microscope Axiolab. A1 with the monitor and camera attached using the lenses of 10X, 20X and 40X magnification. The characterization based on morphologic data and the dichotomous keys used allowed identifying the typhlocybino found as Empoasca insularis Oman, which constitutes the first report in Cuba. [ABSTRACT FROM AUTHOR]

The objective of the present work was the determination of the spatial and temporal pattern distribution of Empoasca spp. and its relationship with weather variables of interest in a 26 ha black bean field (variety Cuba Cueto 25-11) in the municipality of Güines, Mayabeque, Cuba. In the first trimester of 2015, 90 plants were sampled each seven days. The spatial pattern distribution was calculated using Taylor´s power law (LPT): s2 = amb. The population curves were determined from the population density per sampling, and a principal component analysis was used to determine the relationship of the populations with the climate factor. The spatial distribution of the leafhopper population tended to the aggregation, and the nymph and adult population curves had a similar behaviour with a population peak in the second sampling. The sampling of twenty plants instead of thirty was determined to be enough. Humidity, temperature, and wind velocity were the variables with the greatest impact on the behavior of the leafhopper population. [ABSTRACT FROM AUTHOR]

The objectives of this study were the identification of the species of leafhoppers present in a production field of bean (Phaseolus vulgaris L.) (Cuba Cueto range 25-11) in Güines, Mayabeque, Cuba, and the observation of their relationships with disease symptoms on the plants. For this, 30 plants from three plots were sampled every seven days from January to March 2015. The collected insects were cleared and mounted on slides to be identified using taxonomic keys. A cladogram was constructed to analyze the relationships between disease symptoms on the plants and the insects. The leafhoppers identified were Empoasca kraemeri Ross and Moore, Empoasca fabae Harris, and Empoasca papayae Oman. The plants showed symptoms representative of hopperburn, phytoplasma and virus diseases, which were related to vectors. [ABSTRACT FROM AUTHOR]

With the aim of identifying the presence of phytoplasmas in insects and leaves, forty leafhopper adults and 50 leaves of three plants with symptoms associated with phytoplasmas, were collected at the municipality of10 de Octubre, Havana, from February to April 2015. For leafhopper taxonomical identification by using dichotomic keys, they were mounted on flat slides under a Stemi DV4 stereo microscope and observed under an AxioLab. A1 microscope with a monitor and camera attached. Phytoplasmas were detected by extracting the DNA by the 2% CTAB method and using universal primers for the generic amplification of the region ADNr 16S (R16mF2/R16mR1, R16F2n\R16R2). For the first amplification, the combination R16mF2 and R16mR1 was used, and R16F2n/ R16R2 for the nested reaction. The products of amplification were analyzed by electrophoresis on agarose gel (1%). The profiles obtained were compared with phytoplasma positive controls from Catharanthus roseus (L.) G. Don. plants. The leafhoppers identified were Empoasca canavalia DeLong and Empoasca papayae Oman, and the presence of phytoplasma was found in leaves with symptoms as well as in the insects. The presence of these two leafhopper species and phytoplasmas in chaya and insects are the first reports in Cuba. [ABSTRACT FROM AUTHOR]

The aim of this work was to identify the mite fauna on plants of chaya (Cnidoscolus chayamansa (Miller) IM Johnst.) growing in the municipalities of Diez de Octubre and La Habana del Este, Cuba. Thirty leaves collected from the plants with symptoms from February to April 2015 were examined under a Stemi DV4 stereomicroscope; the individual adult specimens were cleared, mounted on microscope slides, observed under an Axioscope microscope with a 40x lense, and identified using the corresponding dichotomous keys. The phytophagous mites Polyphagotarsonemus latus (Banks), Eutetranychus banksi (McGregor), and an unidentified species of the Eriophyidae family were found, as well as the predator Neoseiulus longispinosus (Evans). These mites are reported on chaya for the first time in Cuba. [ABSTRACT FROM AUTHOR]

Generally, the densities of phytophagous insects decrease in the field after an intense rain. For evaluating this assumption and demonstrating the coexistence of pests in the bean crop, the insect pests present in the common bean variety BAT 306 were sampled from December 2015 to March 2016. The samples were always taken the day after a rainy day. A five fixed quadrant design was used. Population density was monitored from the day 32 after planting by counting the leafhoppers, thrips, and whiteflies on five random plants in each quadrant. Taylor’s power law was used to determine the spatial pattern distribution of the insects with the highest incidence; population dispersion per sampling was graphed. Inter-specific competition was evaluated using mathematical models, and an analysis of principal components was made to determine the relationships between the populations and some climatic factors. The average density of whiteflies was less than 0.28 individuals by sample. The leafhopper was identified as Empoasca kraemeri and the thrips as Thrips palmi. These two species populations were shown to coexist with an aggregate pattern distribution and an intrinsic rate (rm) of 0.11 and 0.09, respectively, once the crop reached the reproductive stage. Despite the inverse relationship between the accumulated precipitations and the population levels, rainfall values over 60 millimeters did not achieve density zero. Wind speed, deficit of saturation, and sunshine were directly related to the densities of these vector insects. [ABSTRACT FROM AUTHOR]

The bean thrips Megalurothrips usitatus Bagnall (Thripidae: Thysanoptera) recently became an important pest for legume crops in Cuba. The objective of the work was to determine the influence of the climate and crop phenology on the population density of M. usitatus. From September to December 2020, the common bean cv. Triunfo 70 was sampled weekly in a 0,70 ha area belonging to the National Center for Animal and Plant Health (CENSA), San José de las Lajas, Mayabeque province. The collected specimens were preserved in 70 % alcohol for later identification at the Entomology-Acarology laboratory; in addition, the thrips were counted per plant and recorded. With the data obtained and the climatic variable records, a correlation was made to know the influence of the climate on the insect populations. Thrips populations were present from the appearance of the first trifoliate leaves until the end of the crop cycle, with a population peak in the pod filling stage. This peak coincided with the lowest relative humidity values and the decrease of wind speed. Megalurothrips usitatus resulted the species of thrips with the highest presence in the common bean crop during the period studied. [ABSTRACT FROM AUTHOR]

The population fluctuation of Diaphorina citri Kuwayama and its parasitoid Tamarixia radiata Waterston was determined in urban areas of the municipality of Playa, Havana City, Cuba. The study was carried out from February 15, 2007, to April 15, 2009. The populations of both insects on plants of Murraya paniculata L. (Jack) and Citrus spp. growing in private and public gardens were evaluated every ten days. In order to understand the interactions between the target pest and its parasitoid, logistic regressions,working with a nonlinear model, were used, and the generalized relationship between the samplings were used to determine the density in which a control treatment was necessary. The population of both insects on M. paniculata plants was higher in 2009; in the case of the natural enemy, the population doubled that observed in 2007. The lowest percentages of parasitoidism were found in the citrus plants. The maximum increase rate (K) of D. citri was 147, which exceeded the rate found during the samplings, with a mean population (ì) of 110.9 individuals and a net instantaneous growth rd = 0.06 ; for the parasitoid (K) was 98.25 individuals, a value higher than that observed for the samples, with a population mean (ì) of 53.4 individuals. With these results, it was estimated that, when a total of 49 individuals was present per each five sampled buds, it would be necessary the application of some measure to avoid the quick increment of D. citri. [ABSTRACT FROM AUTHOR]

Los cítricos están entre los cultivos de mayor importancia económica a nivel mundial. Como muchos otros, están plagados de numerosas enfermedades causadas por diferentes agentes etiológicos. De todas las enfermedades de los cítricos descritas hasta ahora, Huanglongbing se considera como la más destructiva y letal; la bacteria candidatus Liberibacter spp. es quien la causa y la transmite Diaphorina citri Kuwayama (Hemiptera: Liviidae). El método más usado para el control del vector es la aplicación de productos químicos, lo cual ha traído como consecuencia el desequilibrio ecológico, la resistencia de insectos a plaguicidas, la aparición de plagas secundarias y la disminución de los enemigos naturales. Ante esta problemática, actualmente se busca establecer un control biológico sobre esta plaga mediante el uso de depredadores o parasitoides; alternativa que ha producido resultados promisorios mediante el uso de Tamarixia radiata (Waterston), parasitoide específico del vector, con efectividades entre 30-97%. En el presente trabajo se establecieron las potencialidades de T. radiata como control biológico de D. citri mediante el estudio de las características biológicas y poblacionales, tanto de la plaga como del parasitoide. Se destaca el corto ciclo de desarrollo del parasitoide, su alta capacidad de crecimiento poblacional con respecto al hospedante, su respuesta funcional de tipo, su alta eficiencia de búsqueda y los altos porcentajes de parasitoidismo. Se desarrolló además, por primera vez, un modelo matemático que incluye la dinámica del cultivo y describe las interacciones de D. citri con su enemigo natural, que puede predecir el incremento y la disminución de las poblaciones como base para decidir momentos de liberación. Estos resultados, unidos a la capacidad de actuar a bajas densidades y su especificidad, constituyeron los principales elementos para la elección de T. radiata como un Agente de Control Biológico promisorio para la regulación de las poblaciones de D. citri. [ABSTRACT FROM AUTHOR]

El control biológico ocupa un lugar preferencial en la regulación de las plagas en cultivos de importancia económica porque constituye una de las principales tácticas empleadas dentro del manejo integrado. Desde el año 2000, el Laboratorio de Entomología-Acarología de la dirección de Sanidad Vegetal del CENSA, trabaja especialmente en el desarrollo de nuevos artrópodos benéficos como agentes de control biológico, sobre la base de estudios ecológicos bajo nuestras condiciones, que permitan sustentar su selección; entre ellos se encuentran los parasitoides Diaeretiella rapae, Tamarixia radiata y los depredadores Amblyseius largoensis, Cryptolaemus mountrouzieri, Nesidioscoris tenuis y Engytatus varians contra plagas presentes en los sistemas de producción de hortalizas y cítricos, o plagas de interés cuarentenario. Se expone el desarrollo de un sistema de cría a campo abierto del parasitoide Diaeretiella rapae como caso de estudio, cuya implementación permitió alcanzar un nivel de parasitoidismo por encima del 90%. Este sistema mostró ser una opción económicamente viable, efectiva y sostenible al no permitir que las poblaciones del áfido Lipaphis erysimi se elevaran, principalmente, cuando el sistema se implantó al inicio de la infestación. El parasitoidismo mantuvo regulado las poblaciones de L. erysimi y los rendimientos alcanzados fueron superiores a 2,5 kg/m², establecido para la variedad de col KKcross. Este sistema puede ser empleado por los productores de la agricultura urbana y suburbana, donde las crucíferas tienen una importante contribución en la producción de hortalizas, así como en programas de manejo, ya que constituye una contribución a la diversificación en el uso de agentes de control biológico, a través de la introducción de nuevos artrópodos benéficos para regular áfidos plagas en el país. [ABSTRACT FROM AUTHOR]