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Artificial intelligence techniques are now widely used in various agricultural applications, including the detection of devastating diseases such as late blight (Phytophthora infestans) and early blight (Alternaria solani) affecting potato (Solanum tuberorsum L.) crops. In this paper, we present a mobile application for detecting potato crop diseases based on deep neural networks. The images were taken from the PlantVillage dataset with a batch of 1000 images for each of the three identified classes (healthy, early blight-diseased, late blight-diseased). An exploratory analysis of the architectures used for early and late blight diagnosis in potatoes was performed, achieving an accuracy of 98.7%, with MobileNetv2. Based on the results obtained, an offline mobile application was developed, supported on devices with Android 4.1 or later, also featuring an information section on the 27 diseases affecting potato crops and a gallery of symptoms. For future work, segmentation techniques will be used to highlight the damaged region in the potato leaf by evaluating its extent and possibly identifying different types of diseases affecting the same plant. [ABSTRACT FROM AUTHOR]

In order to detect potato crop pests from symptom images, a web platform was developed to facilitate the diagnosis of early and late blight from images of affected leaves. The Python programming language, the Flask framework, Bootstrap for platform styling, the necessary libraries, and Pycharm as development environment were used. Image recognition and artificial intelligence software tools, specifically artificial neural networks, were used to implement the diagnostic module. The system also includes the field monitoring record with the incidences of pests, allows incorporating new data, and provides information on management in correspondence with climate variability. For the diagnosis validation, images of symptoms confirmed by experts were taken. The neural network model used was 94.6 % accurate. Future work will include the detection of viruses, bacteria and other fungi from images. The tool is a useful and novel application at the service of agri-food safety, serving as a coordinated platform for plant protection technicians and farmers involved in potato cultivation. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza (HPAI) is a major global animal health problem with public health implications. The aim of this study was to estimate the magnitude of the consequences of HPAI virus incursion in Cuba and the effectiveness of the main control measures. A spatial stochastic model was used to represent biological, environmental and human interaction processes involved in transmission. NAADSM (v.3.3.2) tool was used for parameterization and simulation of the outbreak, and R (v. 3.5) tool for statistical analysis of outbreaks. Four hundred sixty-seven poultry farms in 216 scenarios were processed by evaluating 20 parameters associated with probability functions or linear models to represent the epidemic process of Susceptible-Infectious-Removed (SIR) model in the population studied. Simulation showed depopulation was able to stop the outbreak in all scenarios; however, the greatest animal losses were evident in scenarios with poor biosecurity, slow detection speed and reduced movement restriction. Adjacent farms within a 5 km radius had a significantly higher risk of spreading the virus to a greater extent. The model suggests that it is possible to contain the spread of HPAI virus if detection is reached within three days post-infection, and depopulation is completed within six days. [ABSTRACT FROM AUTHOR]

With the objective of providing information for monitoring the bean flower thrip (Megalurothrips usitatus (Bagnall), a study of their spatial pattern was carried out using geo-statistical techniques. Nine samples were taken weekly from a 0,75 ha plot in San José de las Lajas, Mayabeque province, Cuba, during the October-December 2020 campaign. The population of nymphs and adults of thrips was counted in 25 sampling points placed equidistant 0,6 meters on each diagonal. To determine the spatial distribution, semivariograms were performed by sampling and extrapolating by kriging. Predictive maps were made to identify foci with the largest population and the best time to take control measures. The structural analysis showed that the spherical model offered the best fit and the spatial dependence of the points was high in almost all samples. The insect showed an aggregated distribution pattern and the population foci, identified as key points to carry out the application of natural control or other management measures, were concentrated in the center of the field. [ABSTRACT FROM AUTHOR]

In Cuba, there is little information on the foot pathologies affecting cattle, and these constitute a problem of animal welfare under production conditions. In the present study, 384 dairy Siboney de Cuba cows were examined, which represented 100 % of milking cows from six dairy farms in Artemisa province. The prevalence of lesions was calculated and the logistic regression analysis was performed to determine the risk factors associated with these pathologies. Fifty-six cows were detected with foot lesions (14.58 %), of which 53.57 % presented first degree of lameness. The most affected members were the hind legs (66.26 %) and, of these, the side hooves with the highest number of lesions. The main pathologies diagnosed were: pathological deformations of the hoofs, ulceration of the sole and white line disease. It is concluded that poor drainage and sleeves in poor condition were the main risk factors for the presentation of foot lesions in the cows studied. [ABSTRACT FROM AUTHOR]

In order to know the fauna of arthropods present in tomato (Solanum lycopersicum L.) and bell pepper (Capsicum annuum L.), periodic sampling was carried out on these crops between November 2017 and November 2018 in the suburban farm "Las Piedras", located in the municipality of Guanabacoa, Havana, Cuba. One thousand eight hundred and fifteen insects belonging to seven orders (Hemiptera, Thysanoptera, Lepidoptera, Coleoptera, Diptera, Hymenoptera, and Neuroptera) were collected in the surveys. The order Hemiptera was the most represented in both crops. It was found that Bemisia tabaci Gennadius Biotype B was the most abundant insect in the farm, followed by Liriomyza trifolii Burgess and Aphis gossipii Glover. The thrips Frankliniella schultzei Trybom, Frankliniella williamsi Hood, Thrips tabaci (Lindeman), and Frankliniella fusca Hinds showed low abundance. Several species of natural enemies were also identified, including the myrid Nesidiocoris tenuis Reuter, the parasitoid Diaeretiella rapae McIntosh and some Coccinellidae species. It was possible to appreciate that, in spite of having natural enemies reported as efficient; the natural regulation of harmful organisms was low. The results showed the need to enhance the presence of beneficial arthropods that reduce the populations of insect vectors in the farm. [ABSTRACT FROM AUTHOR]

The response of 19 foreign genotypes and 21 national genotypes to the African cassava mosaic virus (ACMV) was evaluated, and the disease incidence and severity were analyzed. The total number of the plants planted by genotypes at the Namibe Agricultural Experiment Station, Angola, was sampled in February 2017, June 2017, and February 2018. The whitefly adult density per genotype was averaged to calculate the density index on each date, which was compared using a simple analysis of variance and the Duncan's multiple range test for a confidence level of 95 %. The cluster analysis showed that the genotypes were grouped according to the disease severity. Some genotypes were detected with high severity indexes (0.8-1); however, TMS-84004, TMS-0276, TMS-300027, TMS-40142, TMS-800098, TMS-3021, TMS-300027, TMS-42025, Mz-3, Kassakala, and Canfufu, showed severity indexes of 0.2, the lowest index obtained. This result allowed suggesting genotypes that under high vector density conditions showed lower rates of disease severity, which can be used under adequate pest management conditions. [ABSTRACT FROM AUTHOR]

The objective of this work was to determine the probable occurrence of the mixed infection phytoplasma - BGYMV in Phaselous vulgaris L. and the symptoms associated. This probability was calculated using classical probability and a smoothed adjustment of the series of not centered moving median was used to estimate the presence of a mixed infection in two close points. The conditional probabilities of a mixed infection knowing the a priori probabilities of phytoplasma and begomovirus were calculated using the classical formula of probability. The influence of present symptoms in the agricultural ecosystem on the probability of this mixed infection to increase and its association with the vector presence were evaluated using principal component analysis and canonical discriminate test. The occurence of a mixed infection was more probable when it was known a priori that the phytoplasma was present than when it was the begomovirus. Symptoms in the bean crop associated with the mixed infection were wrinkled leaves, mosaic, and reduced size of the leaves. Even in the presence of the vector, leaf chlorosis and deformation were associated with a low probability of mixed infection, which suggested the presence of a unique virus or another disease. We suggest that this association can be used in the prediction of mixed diseases as an initial prognosis leading to a rapid diagnosis with reduced costs due to a better selection of samples. [ABSTRACT FROM AUTHOR]

This article is a review of the selection of mathematical models for population dynamics and the computer systems used for their simulation. Some examples of models that simulate pest dynamics and the advantages and disadvantages of statistical tools used for modeling are shown. It was evidenced that, despite the advances in Information and Communication Technology in Cuba and the rest of the world, there are no computer systems of easy access and use for the simulation of the processes in the mathematical modeling for pest control. Therefore, it is highlighted the importance of implementing an effective and friendly computer tool that allows the simulation of mathematical models to interpret the relationships established between the pests and their natural enemies in the ecosystems and the making of decisions for their management. The review includes the steps to follow in the simulation of population dynamics and shows some of the advances in this matter achieved in Cuba. [ABSTRACT FROM AUTHOR]

Copyright of Revista Didasc@lia: Didáctica y Educación is the property of Universitaria de Las Tunas, Centro de Estudios de Didactica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fitosanidad is the property of Instituto de Investigaciones de Sanidad Vegetal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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 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]

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]

The structure of the mite communities were compared in San José de las Lajas municipality, Mayabeque province, Cuba, before and after the introduction of Raoiella indica Hirst to establish its ecological impact on the mite fauna present on selected species of the families Arecaceae and Musaceae . The selected botanical species were Cocos nucifera L., Adonidia merrillii (Becc.) Becc., Dypsis lutescens (H. Wendl.) Beentje & J. Dransf., Roystonea regia O.F. Cook, and Musa spp. The abundance of the mites detected by functional group was calculated and different ecological indices were applied. The introduction of R. indica into San José de las Lajas municipality caused a reduction of the associated-mite richness in the evaluated plant species, which was particularly marked in coconut and garden palm due to the reduction of predatory mites. A significant increase in the family Tenuipalpidae was observed, due to the high populations of R. indica recorded on C. nucifera, A. merrillii and Musa spp., to the detriment of representatives of the families Tetranychidae and Eriophyidae, which were majorities in the first sampling period. The existence of a rearrangement of the mite species and their abundance was demonstrated, being evidenced by the reduction of species diversity and the increase of dominance, in response to population increases of the invasive exotic mite, which could cause imbalances and affect biodiversity over time. [ABSTRACT FROM AUTHOR]

The objective of the research was to determine the effect of biochar enriched with worm humus and arbuscular mycorrhizal fungi (AMF) on growth and galling of yam plants and M. incognita reproduction. The study was developed under semi-controlled conditions in a biological isolator of the Instituto de Investigaciones de Viandas Tropicales (INIVIT), Santo Domingo, Villa Clara Province, Cuba, in 2022. A completely randomized design with seven replicates was used. The treatments consisted of different combinations of soil, biofertilizers, and biochar, with and without inoculation of a pure population of M. incognita established at the institute. The best development of yam plants was obtained in the treatment where, in the absence of M. incognita, the plants were grown in a substrate containing a mixture of biochar + humus and mycorrhizae as inoculant. It was evident that M. inognita parasitism affected the development of the cultivar 'INIVIT Ñ-2008' because of the decreases produced in plant stem length and fresh and dry matter of the foliar part. The potentialities of incorporating AMF, humus, and biochar in the production technology of D. alata were evidenced by the positive effects on plant growth and development and reduction of M. inognita galling index and reproduction on this cultivar, which was cataloged as a good host and susceptible to this nematode; results which will be corroborated in subsequent field studies. [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 experiment was conducted under semi-controlled conditions from January to March 2017 with the objective of determining the duration of the life cycle of Meloidogyne incognita (Kofoid y White) Chitwood and the egg production per adult females on plants of the common beans (Phaseolus vulgaris L.) cultivars 'BAT-306' and 'Triunfo- 70'. The pots with the plants inoculated with 2000 J2 from a pure population of M. incognita were maintained at 28°C in isolators at CENSA and irrigated every other day. For the analysis of the life cycle, the roots were washed with tap water, examined externally, and the swollen areas or with well-defined galls were opened to count the different larval stages and mature states. Once the first mature females appeared, the evaluation was continued until 96 hours after the appearance of females with eggs. From the samples of plants with roots that contained eggs, 20 females with their eggs were taken at random daily, and the number of eggs x female-1 was counted. The presence of J2 on the plants of both cultivars started being detected 24 hours after inoculation. 'BAT-306' resulted a susceptible cultivar, and M. incognita cycle was completed in 28-29 days, while the cultivar 'Triunfo-70' was resistant and the nematode did not complete its biological cycle. [ABSTRACT FROM AUTHOR]

In order to determine the diversity of phytophagous and predators mites in agroecosystems of the farms "El Caimito" and "Dos Rosas", Cotorro municipality, Havana, Cuba, periodic samplings were carried out from February 2018 to March 2019. In all the samplings, 100 simple leaves per plant were selected, which were reviewed under a stereoscopic microscope (Carl ZeissTM, StemiTM DV4 model). The collected adult mites were clarified and mounted on slides. For their identification, they were observed with a Carl ZeissTM microscope, model AxioSkope.A1 and the corresponding taxonomic keys were used. The relative abundance and frequency of each species were calculated, the species accumulation curve was made and the ecological indices were determined by type of ecosystem. As a result of the inventory, eleven families of mites were detected. The phytophagous mites were represented by three families (Tarsonemidae, Tetranychidae and Tenuipalpidae) and six morphospecies, five families of predatory mites (Bdellidae, Cunaxidae, Stigmaeidae, Eupodidae and Phytoseiidae) with 17 morphospecies and four families of mites with varied eating habits (Acaridae, Tarsonemidae, Tydeidae, and Oppidae). The no disturbed ecosystem, represented by plant species in natural habitats, was the most diverse. Agroecosystem management practices were shown to influence the relative abundance and frequency of species, impacting the diversity of ecosystems. [ABSTRACT FROM AUTHOR]

In order to determine the diversity of mites in the farm "Las Piedras", Guanabacoa municipality, Havana Province, Cuba, periodic sampling was carried out between June 2018 and April 2019. In each sampling, 100 simple leaves per plant species were selected, which were examined under a stereoscopic microscope (Carl ZeissTM, StemiTM DV4 model), and the adult mites were clarified and mounted on slides. The corresponding taxonomic keys were used for their identification. The relative abundance and frequency of each species were calculated, the species accumulation curve was made by the Clench equation and the ecological indices by types of ecosystem were calculated. As a result of the inventory, nine families of mites were detected; two of them were phytophagous mites (Tarsonemidae and Tetranychidae), four of predatory mites (Bdellidae, Cunaxidae, Stigmaeidae and Phytoseiidae) and three of mites with varied feeding habits (Acaridae, Tydeidae and Oppidae). The parameters and values estimated by the Clench species accumulation model indicated that the inventory results were reliable. A differential behavior was observed in the relative abundance and frequency of the phytoseid mite species as a function of the management of the ecosystems. The species I. quadripilis were very abundant and very frequent in the undisturbed ecosystem, while E. hibisci and Agistemus sp., were very abundant and frequent in the little disturbed ecosystem. The little disturbed ecosystem, represented by the fruit species, was the most diverse. Among the detected species, I. quadripilis and E. hisbisci stood out for presenting the greatest possibilities of use as biological control agents of harmful organisms in the farm "Las Piedras". This knowledge will make possible to establish the most favorable agroecosystem management practices for the conservation of these important natural enemies. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate in vitro antagonism of 13 Cuban Trichoderma asperellum Samuels, Lieckfeldt & Nirenberg (Ta.) strains against Alternaria solani Sorauer. The modes of action of T. asperellum strains against A. solani in dual culture were determined. The results showed differences between the antagonist strains. The strains Ta. 90, Ta. 78, Ta. 75, and Ta. 85 were highlighted by their antibiotic effect. In the space competition, only Ta. 85 colonized 100 % of the pathogen (Bell et al. scale Grade 1.), while Ta. 17, Ta. 3, Ta. 90, Ta. 78, and Ta. 28 had more than 80 % growth over A. solani (Grade 2 of the scale). However, Ta. 75, Ta. 78, Ta. 79, and Ta. 85 strains proved to be good space competitors against the pathogen, with more than 50 % inhibition of radial growth of the pathogen. The strains Ta. 13, Ta. 56 and Ta. 85 had four hyphal interactions with A. solani; the most observed were vacuolization, penetration and granulation. The strains Ta. 1, Ta. 3, Ta. 12, Ta. 13, Ta. 25, Ta. 28, Ta. 56 and Ta. 85 caused significant reduction of the area occupied by the pathogen at 400 h, relative to the size at 96 h. The strains Ta. 85, Ta. 1 and Ta. 12 were highlighted in this action; the strain Ta. 85 was selected as the most promising; however, Ta. 28, Ta. 56 and Ta. 13 showed good qualities for evaluation in field conditions. [ABSTRACT FROM AUTHOR]

To determine the reproduction and pathogenicity of nematode Meloidogyne incognita (Kofoid and White) Chitwood on chickpea cultivar 'Nacional-29' were the objectives of this work conducting in semi-controlled conditions. Using 1 kg capacity pots, four treatments were establishing in correspondence with the following initial nematode population levels (Pi) with 0 (control); 1,5; 2,5 and 5 eggs and second stage juveniles per gram of substrate. The experiment was conducted during 35 days and, at the end of this period, the stem/leaves and roots fresh biomass, number of galls in roots, Root galling index, final population and the Reproduction Factor were determined. The data were analyzed through Simple Variance Analysis and the relationship between Pi and the stem/leaves fresh biomass was determined by regression analysis. The chickpea 'Nacional-29' cultivar was good host and susceptible to M. incognita, with variable values and superior than 1. The root biomass showed statistic differences between treatments and stem/leaves fresh biomass decrees with the increment of initial population levels of M. incognita. The negative impact of increased initial population of M. incognita in 'Nacional 29' chickpea cultivar, aspect that the farmers must take in consideration. [ABSTRACT FROM AUTHOR]

With the aim of determining the prevalence of Ancylostoma caninum in dogs from eight municipalities of Havana province, a coproparasitoscopic analysis and a haematological study (total leukocytes and blood differential test) were carried out in 299 dogs. Data related to age, sex and previous treatment with antiparasitics were obtained. The results of the blood differential test and the eosinophil count were compared according to sex, age group (adults and puppies) and place of origin (municipalities). In the blood differential test, the eosinophil count showed a significant difference (p.0.05) between the place of origin (municipalities) and the age of the animals. The coprological results showed 49.2% prevalence of Ancylostoma caninum, without showing significant difference (p.0.05) when comparing the municipality of origin, age and sex. There was a concordance of 93.3% and Kappa index of 0.87 was found between the presence of eosinophilia and positive cases of Ancylostoma caninum by coprology. [ABSTRACT FROM AUTHOR]

El tomate es uno de los cultivos de mayor interés para los agricultores de la provincia Namibe; se desarrolla en sistema convencional y los niveles de producción que se alcanzan son bajos, debido al ataque severo de plagas, principalmente de Heliothis armiguera. Por tal motivo, el presente trabajo estuvo encaminado a evaluar la afectación por esta plaga en cuatro sistemas de manejo. Durante la campaña mayo-octubre 2014, se realizó el muestreo de H. armiguera en las variedades IPA y Río Grande, en cuatro plantaciones de la Estación Experimental Agrícola de Namibe (Manejo agroecológico y riego por goteo, manejo agroecológico y riego por gravedad, manejo convencional y riego por gravedad, sin empleo de productos y riego por gravedad). Se efectuaron tratamientos fitosanitarios de acuerdo al sistema de manejo y solo se realizaron podas y deshije en el manejo agroecológico, sistema que incluyó el uso de trampas de colores, barreras vivas y asociación con maíz, Fitomas, Aceite de nim, Bt, azufre y Maconzan. En cada plantación se monitorearon 0,125 ha. A partir de 30 días después del trasplante, y con frecuencia decenal, se realizaron muestreos del tipo secuencial, de 10 plantas por parcela de cada variedad en cada sistema. Se determinó el número y el peso de frutos totales, frutos comerciales y frutos no comerciales (afectados por H. armiguera). Los altos niveles poblacionales de la plaga incidieron en la obtención de bajos rendimientos. En la plantación testigo se obtuvo, aproximadamente, 8 frutos por planta, de lo cual solo resultó comerciable menos del cinco por ciento. Tanto en la plantación que se dejó como testigo como en la que se aplicó manejo convencional, la variedad IPA fue la más afectada (91,8 y 83,4% de frutos no comerciales, respectivamente), la variedad Río Grande, aunque en menor grado, también presentó altos niveles poblacionales de H. armiguera. Sin embargo, en ambas variedades con manejo agroecológico, independientemente del tipo de riego, se presentó bajo nivel poblacional de la plaga y la afectación en rendimiento fue menor (entre 70 y 77% de frutos no comerciales). Se recomienda aplicar el manejo agroecológico y evaluar otros factores que inciden en la obtención de los bajos rendimientos. [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]

To determine the resistant/ susceptibility behavior of the soybean (Glycine max L.) cuban cultivar INCASoy-36 to M. incognita and the damage that different population levels may cause. The inoculum was preparing using NaOCl and four treatments were established: control (whiteout nematodes) and three population levels (1.5; 2.5 and 5 eggs-juveniles per gram of soil-1), with complete random design and 7 replicas. The Root Galling Index (IA), Reproduction Factor (FR), and with these data, the categories as host or not and Resistant / susceptible were establish at 35 days. The parameters plant high;leaf, flowers and legume numbers were determined; beside steam diameter and fresh weigh. The data were analyzed by Simple Variance Analysis and the media were compere (p<0.05). For determine the relation between nematode population levels and some develop parameters the regression analysis PROC GLM, using SAS (Version 9.0 SAS) were used. INCASoy-36 do not was host for M. incognita race 2, with reproduction factors between 0.1 and 0.9, showing it resistant behavior because the nematode can't reproduce; nevertheless, the high (R2 = 0.751) and fresh weigh (R2 =0.859) were significantly affected; beside the leaf, flowers and legumes number. According to the results, the cultivar is classified as resistant and intolerant to M. incognita. [ABSTRACT FROM AUTHOR]

The objective was to determine the multiplication rate (FR) of Meloidogyne incognita (Kofoid and White) Chitwood and its effect on plant height, stem diameter, number of leaves, flowers and beans (legume) of the common bean cultivar 'Cuba Cueto 25-9'(Phaseolus vulgaris L.). The studies were carried out under semi-controlled conditions for 35 days. Three different inoculum rates (1.5, 2.5, and 5 of second stage juveniles (J2) and eggs per gram of substrate) were used by means of Initial population (Pi). The reproduction Factor (FR), Root Galling Index (IA), and the plant development parameters above mentioned were determined. The data were statistically analyzed and compared (ANOVA, Duncan (p<0.05)). The relationship between plant high, and Pi was determined by regression, using Statistic Package SAS, Version 9.0. The nematode parasite and reproduce in common bean 'CC-25-9' with values of FR=1.6, 6.1 and 6.2. The IA=3, 3.6 and 3.8 in the treatments with Pi=1.5, 2.5 and 5 (J2) and eggs x gram of substrate-1, respectively. The initial population levels (Pi) reduced plant height (R²=0.70) significantly. There were no substantial differences among the treatments; however, a tendency of the plant stem diameter and the numbers of leaves, flowers and beans to be reduced by the nematode was observed when they were compared with healthy plants. We discuss the practical importance of the use of plants belonging to the same species to evaluate the resistance/susceptibility of a cultivar to Meloidogyne spp. [ABSTRACT FROM AUTHOR]

Within the techniques of conservation biological control, the use of alternative host plants is very common at present, mainly for biological control of aphids by using their parasitoids. The aim of this study was to establish a proposal of an alternative tritrophic system for the rearing of parasitoids. The biological and population attributes of the green corn aphid (Rophalosiphum maidis (Fitch) (Hemiptera: Aphididae) were evaluated on sorghum [(Sorghum bicolor (L.) Moench)] under laboratory conditions (25.55 ± 1 ° C temperature and 68.25 ± 10% relative humidity). One hundred newly emerged nymphs were individually placed in Petri dishes containing sorghum leaf disks water agar (1 %). Daily observations were made to determine the duration of the nymphal, pre-reproductive, reproductive, and post-reproductive periods. With these data, the values of fertility, longevity, and duration of the development and life cycles were calculated. R. maidis reached the adult stage in 7.89 days with a life cycle of 12.01 days on sorghum, reaching high population levels and population increases of about 12 % daily. These biological studies of R. maidis on sorghum are the first carried out in Cuba, and they ratify the reproduction potential of this aphid on the crop. [ABSTRACT FROM AUTHOR]

The genetic variability among 32 maize (Zea mays L.) accessions collected in different regions of Pinar del Río and Guantánamo, Cuba, and 5 commercial varieties was analyzed by using RAPD markers. The dendrogram resulting from using Ward's method and Jaccard's distance showed the formation of four groups that are related to the origin of the accessions and the phenotypic characteristics of the grain which was corroborated with a factorial correspondence analysis. This result allowed knowing the genetic variability in the maize crop among the places studied, which is an advantage for breeding programs, the conservation of the germplasm bank, and the management of pests and diseases. [ABSTRACT FROM AUTHOR]

Mulberry (Morus alba L.) is a multipurpose plant with potentialities that have been exploited in the pharmaceutical, textile, and agricultural branches. In order to determine the diversity of the entomofauna associated with this crop, an inventory was carried out for the first time in areas of the "Los Mangos" farm in the municipality of Playa, Havana. From February 2018 to February 2019, 12 samplings were carried out. A total of 75 plants were taken per sampling, which started 30 days after the crop had been cut up to 90 days. . The sampled plants were examined from the base to the apex, and the collected specimens were mounted and identified following the corresponding taxonomic keys. With the data obtained, species accumulation curves were constructed, tritrophic relationships were established, as well as abundance, relative frequency, and diversity indices were calculated. A total of six insect orders, 16 families, five genera, and eight species were identified. The best represented order was Coleoptera. Bemisia tabaci, Diabrotica balteata, Empoasca sp, and Pachnaeus litus are new hosts in the crop. The exponential model provided the best estimate of the real number of accumulated families. Five tritrophic relationships were established. The most frequent families were Pseudococcidae, Cicadellidae, Pyralidae, and Actiidae, with phytophagous species, and Coccinellidae and Crysopidae, with natural enemy species . The most abundant family was Pseudococcidae. The indices showed the locality had low diversity with predominance of high dominance. These results facilitate the establishment of practices for the conservation and increase of natural enemies of harmful organisms present in the crop. [ABSTRACT FROM AUTHOR]

To determine the spatial disposition pattern of Myzus persicae Sulze and predict the evolution of its dispersal in a potato crop (Solanum tuberosum L.), an area of 0.5 ha of the variety 'Gazelle' was monitored in the experimental fields of the National Institute of Agricultural Sciences (INCA), Mayabeque, Cuba. Weekly samplings were carried out during the vegetative growth of the crop. In each sampling, 40 geo-referenced fixed plants were examined and the aphids present on each plant were counted, and samples were collected for identification. The aphid population density per sampling was calculated, and the exploratory analysis of this variable was carried out. The spatial disposition of aphids was determined according to indices for sampling units that were not necessarily contiguous. The geostatistical data analysis was carried out by elaborating population density maps using the ordinary Kriging technique. M. persicae proved to be the predominant aphid in the crop. The disposition indices used indicate an aggregated population distribution on most of the sampling dates. Field location, size and density of M. persicae aggregates in the potato crop were highly variable. Kriging predicts the existence of areas of unstable aphid density, and it is estimated that the population will invade a large part of the field. Due to the conditions of this agro-ecosystem, this aphid species in potato follows a trend in which aggregates emerge at the edges and move toward the central zone of the crop. [ABSTRACT FROM AUTHOR]

The objective of this research was to determine the susceptibility / resistance behavior of the cultivars BAT-306 and Triunfo-70 of common bean (Phaseolus vulgaris L.) to Meloidogyne incognita (Kofoid and White) Chitwood under semi-controlled conditions. Pots with 1kg of substrate were used, and the plants were inoculated with a 6 initial population (Pi) geometric series of nematodes (0.125; 0. 25; 1; 4; 16 and 64 eggs and second stage juveniles (J2) per substrate gram-1) population initially isolated from common bean growing in Mayabeque province, Cuba. The nematode final population (Pf) was determined at 60 days, and the Reproduction Factor (RF)= Pf/Pi was determined. The cultivar Triunfo-70 was resistant when Pi was lower than 64 eggs and second stage juveniles (J2) per substrate gram-1, with an RF between 0.23 and 0.9; nevertheless, BAT-306 freely allowed the nematode reproduction, with an RF between 6.1 and 8. The genotypes BAT-306 and Triunfo-70 could be used as susceptible and resistant controls, respectively, in common bean behavior studies in the presence of Cuban populations of M. incognita. [ABSTRACT FROM AUTHOR]

The objective of this work was to determine efficient extraction methods to study the soil nematode communitiy present in ferralitic soils. Soil samples were taken following a stratified random design from onehectare areas chosen in Guines and San Jose de las Lajas (Mayabeque Province, Cuba) The samples were placed in polyethylene bags and taken to the Plant Nematology Lab. of the National Center for Plant and Animal Health (CENSA). The extraction methods examined were the Baermann Funnel technique, the modified Whitehead traywith gauze and milk filter, the two bottle method, and the centrifugation-floatation technique. The quantities of soil processed were 5, 25, 50, 100, 150, 250, and 350 g. The data were analyzed by Principal Component Analysis. The highest quantities of nematodes were obtained by the Whitehead tray technique with both filters and 100g of soil and the centrifugation-floatation technique with 350g of soil. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the preference of the parasitoid Lysiphlebus testaceipes on the aphids Aphis gossypii and Rophalosiphum maidis. Plants of sorghum (Sorghum bicolor L) and egg plant (Solanum melongena L.) were infested with nymphs of the 2nd and 3rd instars of A. gossypii and R.maidis, respectively, and then a newly fertilized female of L. testaceipes was released. From the 3rd day, the parasitoidism percentage and development time of the parasitoid were evaluated. Under the study conditions, L. testaceipes showed a higher preference for R. maidis than A. gossypii, with 54.85% and 38.20% of parasitism in each case. The life cycle was 10.85 days in A. gossypii and about 12.65 days in R. maidis. The results showed that the aphid R. maidis could be used as an alternative host for the reproduction of the parasitoid L. testaceipes on sorghum, a plant used as a barrier in agro-ecosystems. [ABSTRACT FROM AUTHOR]

The biological and population attributes of Aphis gossypii (Glover) (Hemiptera: Aphididae) were evaluated on eggplant and pepper under laboratory conditions. One hundred newly hatched nymphs were individualized in Petri plates containing leaf discs of eggplant and peppers on 1% agar water. Daily observations were made to determine the changes of moults, and the duration of the different instars to reach adulthood and mortality of nymphs was recorded. A. gossypii had a development cycle of 5.97 days on egg plant and 5.29 days on pepper, with a life cycle of 11.91 and 9.97 days, respectively. On eggplant and pepper, respectively, the rm for this species was 0.089 and 0.05, the generation time of 20.72 and 24.57,and the Ro of 6.33 and 3.73 female daughters per mother. The biological parameters of A. gossypii on pepper and eggplant showed that on eggplant the life cycle is lengthened, the generation time is shortened, and the progeny increases. [ABSTRACT FROM AUTHOR]

The effect of four essential oils and eleven selected components on the infective juveniles (IJ) of the entomopathogenic nematode Heterorhabditis amazonensis Andaló et al. strain HC1 was studied under laboratory conditions. Susceptibility of this strain to seven organic solvents and surfactants was determined. The lethal and sublethal toxic effects on IJ exposed directly to the essential oils and components were evaluated in 24 well plates for 24 h. Data of lethal toxic effects were subjected to ANOVA and the means compared by Duncan's multirange test at 0,05 %, whereas data of sublethal toxic effects were analyzed by the multiple comparison of proportions (Wald's Method, confidence level of 0,05). Toxicity of Triton X-100 at 0,5 % on H. amazonensis strain HC1 was low and could be used in bioassays of chemical product compatibility with this nematode strain. The essential oils of Melaleuca quinquenervia (Cav) S.T. Blake and Citrus sinensis (L.) Osbeck caused no significant lethal toxic effect on IJ of H. amazonensis (strain HC1), while those of Piper aduncum subsp. ossanum (C. DC.) Saralegui and Piper auritum Kunth produced moderate mortality. No sublethal effects were caused by these four oils on the infectivity of IJ of H. amazonensis strain HC1. The essential oil components camphene, p-cymene and piperitone did not affect IJ of H. amazonensis strain HC1; 1,8-cineole, limonene, camphor, and methyl chavicol showed moderate toxicity, and carvacrol, eugenol, linalool, and thymol were highly toxic. According to the parameters evaluated, the essential oils from M. quinquenervia and C. sinensis and the components camphene, p-cymene, and piperitone were compatible with H. amazonensis strain HC1. [ABSTRACT FROM AUTHOR]

The aim of the work was to evaluate the development of Podosphaera xanthii (Castagne) U. Braun & Shishkoff in pumpkin crop during the years 2018 - 2019. The crop (Cucurbita pepo L.) (hybrid pumpkin material, Gray Zucchini) was established on a surface of 1 500 m2 where 25 plants were randomly selected, and three leaves per plant were labeled, in which incidence and severity were evaluated weekly using a degree scale. Weather variables were recorded. These results indicate that P. xanthii is present at 14 days after transplantation in the sowing from February to April; while from May to July, it is present after seven days, coinciding with the rainy season, conditions that indirectly favor the increase of relative humidity (23-63 %), causing the progress of the disease. The development of the disease was similar in both years (2018-2019), but not between the two sowing dates, with the first symptoms appearing seven days earlier, and with a severity of 0-9 %, at the second sowing time (May-July). The comparison of major components showed a relationship of temperature with the incidence and severity of the pathogen, but not with rainfall, since this factor does not condition the emergence of the disease. As an important result for Tehuacán region, it is suggested the month of February as the most appropriate date for planting the crop, with a low incidence and severity of the disease. [ABSTRACT FROM AUTHOR]

Predatory mites of the family Phytoseiidae are important in agroecosystems, given their significant role in the regulation of pest mites and small insects. The present work aimed at to determining the diversity of phytoseid predatory mites in Jaruco municipality. For this purpose, an inventory of predatory mites was carried out in selected agroecosystems of the municipality, the mites present were quantified and their taxonomic identification was performed. With the information obtained, species richness, relative abundance, and frequency, as well as derived ecological indices, were calculated. As a result of the inventory, five families of predatory mites were detected. The family Phytoseiidae represented 69.23 % of the detected species and 93.40 % of the inventoried individuals. The 13 species of predatory mites detected were considered new reports for the locality. The species A. largoensis was abundant and frequent, while the remaining species were infrequent and not abundant, except I. quadripilis that was abundant and Tetranychus sp. that was frequent. The ecological indices calculated demonstrated that the locality presented a high diversity. This was demonstrated by the 21 species of mites found, as well as by the values of the Margalef (MDg= 3.76) and Shannon-Wiever (H'= 2.40) indices. Among the predatory mite species found, A. largoensis, A. aerialis, I. quadripilis, N. longispinosus T. subtropical, and E. hibisci stood out with the greatest potential as biological control agents for phytophagous mites. This knowledge will make possible to establish the most favorable agroecosystem management practices for the conservation of these important natural enemies. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the influence of selected abiotic factors on the viability and pathogenicity of H. amazonensis strain HC1, as initial studies to obtain a commercial formulation. Three trials were developed, where infective juveniles (IJ) were maintained under the effect of each factor for several weeks. In the first test, it was evaluated the effect of different types of water (tap water, boiled, distilled and deionized) on JI at the concentrations of 5x104 and 105 IJ per plate (15 cm diameter). The data related to the viability of IJ were processed through the two-factor analysis of variance and the Duncan's multiple range test (95% significance level). Using the water type selected in the first test, three solutions at pH 5, 7, and 9 were prepared and evaluated at the temperatures of 22±1°C, 25±2°C, and 27°C. The values were processed by Wald's test by correction, and CompaProWin 2.0 software was used. The viability and infectivity of IJ in the temperature and pH tests were determined by using the one-in-one test with larvae of Galleria mellonella L. The highest survival values of IJ were obtained with distilled and boiled water, pH 5 and 7, and at temperatures of 22±1° C. [ABSTRACT FROM AUTHOR]

Researches on the detection of mycoplasmas in horses are relatively scarce. However, there are reports about their association to the respiratory-reproductive complex. In Cuba, the presence of these microorganisms in horses is unknown, so the objective of this work was to detect the presence of microorganisms of the class Mollicutes associated to the respiratory-reproductive complex in horses from Mayabeque, Cuba complex in horses from San José de las Lajas, Mayabeque. For this purpose, 97 animals from four localities of this municipality were analyzed. One hundred and thirty-one exudates (97 nasal and 34 preputial) were collected for diagnosis by microbiological culture and PCR. The presence of Mollicutes was detected in 37.11 % of the samples; of these 88.8 % corresponded to nasal exudates and 11.2 % to preputial exudates. The presence of Mollicutes was detected in all localities. Locality "D" and animals older than two years old had the highest number of positive results. An isolate was obtained from preputial exudate, which was identified as Acholeplasma spp. by biochemical tests. Studies related to the presence of Mollicutes in horses are being carried out for the first time in Cuba, so it is necessary to continue studies related to the epidemiology of these pathogens, as part of the control of the respiratory-reproductive complex in this species. [ABSTRACT FROM AUTHOR]

The objective of the study was to establish the behavior of four defense-related enzymes in the common bean cultivars (Phaseolus vulgaris L.) BAT-306 and Triunfo-70 parasitized by Meloidogyne incognita (Kofoid and White) Chitwood. The activity of the enzymatic systems peroxidase (PO), phenylalanine ammonia lyase (PAL), chitinase, and glucanase, as well as the PO isoenzymes were determined. The seeds of both cultivars were sown in a mixture of soil and organic matter in a 3:1 ratio and inoculated with 2000 juveniles (J2) 7 days after germination. For all the analyzes, samples were taken at 1, 3, 5, and 7 days after the inoculation, and the results were compared by an analysis of variance and Duncan's multiple range test, using the InfoStat program. All the systems studied showed induction in both cultivars. In the cultivar Triunfo-70, resistant to the nematode, considerable increases in the activity levels of all the enzymatic systems were induced, and in some of them, these activity increases were more sustained in time, of greater magnitude, or occurred earlier than in the susceptible cultivar BAT-306. [ABSTRACT FROM AUTHOR]

Phytoplasmas are associated with two papaya diseases in Cuba, Papaya Bunchy Top (PBT) and Bunchy Top Symptoms (BTS), which decrease fruit production. Assessment of the 16S ribosomal DNA by nested PCR, conventional RFLP, sequencing and in silico RFLP analyses allowed the identification of a new phytoplasma subgroup designated BTSp-16SrI-Z associated with BTS disease in the eastern region of the country. BTSp-16SrI-Z subgroup was detected in 60.42 % of the surveyed plants with crown leaf chlorosis and necrosis of the young leaves. Results confirmed that this phytoplasma strain was consistently associated with the observed BTS symptoms, implying new epidemiological constraints for the disease management. [ABSTRACT FROM AUTHOR]

Raoiella indica is recognized as a severe coconut pest in different regions of the world because of the damage it causes. Its presence in the largest production pole of the crop in Cuba has motivated the interest in studying the population dynamics of this mite in coconut plantations in the municipality of Baracoa, Guantánamo. For three years, 30 leaflets were sampled at ten-year intervals. Under a stereoscope, eggs, immature stages, adults of R. indica, and predators were counted in three regions of the foliole (base, middle and apex). This allowed graphing the population movements of mite and its natural enemies with the climatic variables and an analysis of principal components was applied. In the first year, the greatest population was reached in the summer months due to the low rainfall and the rise in temperature. In the second year, the lowest average density was observed with only 3.79 mites.foliole-1, caused by the volume of rain accumulated in that period (462 mm). The third year, a period with scarce rainfall and high temperatures, showed the highest average level of mites per leaflet with 123.5. Eleven species of predatory mites were identified and Amblyseius largoensis Muma was the most frequent and abundant. In the analysis of principal components, with a cophenetic correlation value of 0.976, the rainfall and maximum relative humidity were shown to have the highest correlation with the pest in a negative way, while temperature favored the increase of populations. [ABSTRACT FROM AUTHOR]

To determine the capacity of Nesidiocoris tenuis Reuter to regulate populations of Bemisia tabaci Gennadius biotype B, the consumption and functional response of the predator to eggs and nymphs of the pest were evaluated on tomato plants as a substrate under laboratory conditions. This predator showed a higher preference for nymphs (α = 0.6) than for eggs. The average of whitefly eggs and nymphs consumed by the mirid in one day was 100 and 192, respectively. The functional response of N. tenuis females to nymphs described a sigmoid curve, which could be classified as type III. The females of N. tenuis were voracious predators for the immature stages of B. tabaci, which makes this natural enemy a viable alternative for the current biological control methods in tomato in Cuba. [ABSTRACT FROM AUTHOR]

Microsatellite markers and the mitochondrial sequence of mtCOI gene were used for the molecular characterization of the MEAM1 species of Bemisia tabaci (Gennadius) (Hemiptera, Aleyrodidae) in Cuba. Whitefly specimens collected from cucumber (Cucumis sativa L.), sugar beet (Beta vulgaris L.), tomato (Solanum lycopersicum L.), squash (Cucurbita pepo L), fruits of economic interest like papaya (Carica papaya L.), and two species of Bemisia weed hosts like American black nightshade (Solanum americanum Mill) and sage (Salvia officinalis L) were selected in non-productive ecosystems The results made evidente the presence of MEAM1 population with low molecular divergence in all hosts examined. DNA sequencing revealed the coexistence of MEAM1 with the New World (NW) species in S. officinalis L in natural habitat. [ABSTRACT FROM AUTHOR]