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The soil mesofauna comprises a group of arthropods, whose body size ranges from 0.2 to 2.0 mm, and which are important in transforming soil organic matter, recycling nutrients, and improving physical properties of the ground. Within the faunal groups that inhabit the soil, oribatid mites and springtails stand out because of their number, diversity, abundance of species and activity; great aptitude for speciation, short life cycle and little dispersion of species adapted to edaphic life and to different types of soils. Due to these characteristics, these organisms are used as biogeographic-ecological indicators and indicators of the soil quality and health. The use of biochar (Biocarbón in Spanish), as a soil amendment, to improve fertility and mitigate climate change is becoming a common practice. Rice husk biochar was used in three concentrations. Four tomato seedlings (Solanum lycopersicun L.) cultivar L43 were placed in each experimental unit. A composite sample of each treatment was taken weekly and placed in Berlese-Tullgren funnels for seven days. Subsequently, the collected samples were examined under the stereomicroscope and the individuals were separated by morphospecies for their subsequent slide mounting and identification. Arthropods belonging to the groups Insecta (Hymenoptera, Hemiptera, Coleoptera, Lepidoptera), Acari, and Collembola were identified. An increase in the number of Collembola was observed in the treatment with 75% Biochar (rice husk) after 28 days. In the case of mites, the most represented orders were Oribatida (Cryptostigmata), Prostigmata, and Mesostigmata, with an increase in their populations in the containers with 25% Biochar after 28 days. A positive influence of biochar on soil arthropods was demonstrated, expressed by the increase in the number of springtails and soil mites with respect to the control, with an outstanding recovery of soil biological activity in the short term. [ABSTRACT FROM AUTHOR]

Bactericera cockerelli Sulc, the potato / tomato psyllid (Solanum tuberosum and S. lycopersicum), is recognized as a threat to the production of solanaceous crops because it is an efficient vector of the bacterium Candidatus Liberibacter solanacearum (CaLso) in the American continent, Europe, and New Zealand. The biological and genetic characteristics of the insect make its management difficult, and so do the high number of host, refuge. and feeding plants in which it can be found. Furthermore, the influence of climate change has caused psyllid populations to establish and colonize new areas and countries. At present, the psyllid vectors of microorganisms that cause diseases in plants are widely distributed, and studies are being carried out to understand the impact of their populations on intensive agricultural production systems. In the last decade, studies on the application of new biological control and management techniques have also increased aiming to count on fast and efficient alternatives for reducing the effects on crops and economy. A total of 74 scientific papers related to the host plants of these insect vectors, their biological and chemical control strategies, and the novel alternatives for their management were analysed. In order to maintain surveillance over the vector, the present status of the identification of these species in Cuba, the situation concerning the presence of the cultivation system. -psilid-CaLso in the world and the American and Caribbean regions, as well as the possible implications of the presence of these species for the Cuban agriculture were studied in depth. [ABSTRACT FROM AUTHOR]

Global food security could be threatened in the coming years by the emergence and spread of emerging pests in crops. Psyllids are considered as possible destructive pests due to their relationships with some important plant pathogens. Bactericera cockerelli Sulc (Hemiptera: Triozidae) is recognized as an efficient vector of the bacterium Candidatus Liberibacter solanacearum (CaLsol), an invasive pest according to the EPPO, which causes diseases in potatoes, tomatoes, peppers, and other solanaceous and some apiaceous crops. Known the vector-bacteria complex to be present in different countries of the world belonging to the American continent, Europe and New Zealand, 61 scientific papers related to this topic were reviewed. Changes in the climatic variables, the biological distribution of this insect-vector system, the high ecological plasticity that allows this insect to develop different biotypes, depending on the characteristics of the area where it develops, could complicate the control of the insect-pathogen system. These characteristics make necessary a maintained extreme surveillance in those countries where it is not yet present. So far, the bacterium and the vector are not present in Cuba; however, its proximity to countries where it is present, the existence of optimal climatic conditions host plants, and the increasing tourism and international trade, make necessary to offer updated information on this disease, the causal agents and their vectors as a contribution to the preparation of the scientific-technical-productive personnel and other decission makers. [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]

Biological characteristics, consumption, and prey preference of the predatory bug Macrolophus basicornis preying on Myzus persicae or Macrosiphum euphorbiae on tomato plants were studied. Incubation period of the predator's eggs was of 8 days and its nymphs presented five instars regardless of the prey consumed. All the nymphal stages showed a similar development time with the exception of the 2nd instar. There were no significant differences between the size and weight of M. basicornis nymphs feeding on M. persicae or on M. euphorbiae. The average rate of aphid consumption revealed significant differences between the 5th instar nymph and the females of the predator when they had no option to choose the prey. In addition, the fifth nymphal stage consumed significantly more aphids in 24 h than the other stages. The females had a high rate of predation comparable to the fifth nymphal stage. M. basicornis was shown to be capable of completing its cycle on preys like Myzus persicae or Macrosiphum euphorbiae. The biological characteristics and prey consumption by M. basicornis were strongly influenced by the prey species and size, the latter being able to influence the prey preference of the predator. [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 life cycle duration and the ecological parameters of the predator Nesidiocoris tenuis Reuter were determined under laboratory conditions at 26.7 ± 2 ° C, 66.39 ± 10% RH and photoperiod 10:14. For this purpose, tomato plants, Solanum lycopersicum L. var. L43, were used as substrate and eggs and nymphs of Bemisia tabaci Gennadius biotype B as food. The development time for eggs and nymphs of this predator were 11 and 27 days, respectively. The mortality of the immature stages was 28%, the longevity of females 13 days and the sex ratio 0, 56. Other parameters were: the net reproductive rate Ro = 23, the intrinsic rate of increase rm = 0.111 day- 1, the finite growth rate λ= 1.2, the average generation time T = 28.7 days and the population doubling time TD = 6.3 days [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 aim of this study was to evaluate the quality indicators for the mass rearing of Tamarixia radiate Waterston under laboratory conditions. From established quality indicators, the behaviour of the routine parameters for the quality control of Tamarixia radiate on Diaphorina citri Kuwayama was evaluated. Size and length of the middle tibia, emergency percentage, longevity of adults with and without food, deformations, parasitism percentage, and sex ratio were analyzed in 10% of the populations obtained per batch during the rearing process Shewart graphics were constructed with the information obtained. In all generations evaluated, the sex ratio was favorable to females, with a mean of 0.90 ± 0.39. In all cases, the gender analysis showed the female to reach a larger size than the males. No deformations were observed on the wings of the specimens. The mean survival was 2.47 days for females and 1.98 days for males. The parasitism average was 62.58% and the emergency ranged between 74.56 and 80.2%. The indicators were within acceptance values, demonstrating that the production process was under control. The adult average of T. radiata in the ten batches tested was of 340 parasitoids, a value which is within the expected ones, which showed the efficiency of the rearing process under the conditions imposed. [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]

With the aim of determining the duration of the life cycle, survival, sex ratio, longevity, fecundity and other biological and population attributes of Tamarixia radiata Waterson, it was reared on Diaphorina citri Kuwayama on Muraya paniculata (Jack) plants at 70±10% of HR, 28±1p C and 14 :10 LD. The period of premummification and the development cycle was of 3,08 and 7,27 days, respectively, for a total life cycle of 25,62 with a survival of 18,35 days. The parasitism exceeded 70% with an emergence of 72,27%.On the oher hand, the rate of oviposition was 24 eggs / female / day, and a longevity of 23 days, which was higher in females. The time of fecundity for the T. radiata female was 0,94 days and the reproductive growth rate of 333,77 eggs/day . The population parameters such as the intrinsic rate of increase (rm) and the finite rate of increase (λ) showed values of 0,14 and 1,02 respectively, and the net reproductive rate (R0) had an estimated value of 1,55 (daughters female/female mothers). These parameters were compared with those of its host D. citri, and they reaffirmed T. radiata as a potential biological control. [ABSTRACT FROM AUTHOR]

The objective of the present work was to describe the behavior of Megalurothrips usitatus Bagnal populations after the application of BionemC (Heterorhabditis amazonensis Andaló et al. strain HC1) and e-codaoleoK in three common bean (Phaseolus vulgaris L.) cultivars treated with biostimulants and biofertilizers with proven effectiveness in the crop. The experimental work was carried out on the “El Violento 1” farm, in San José de las Lajas municipality, Mayabeque province. Weekly samples were taken from the upper and middle strata of 30 plants of the cultivars 'Triunfo 70', 'Cul 156', and 'Coral 10’ . In each plant, the number of adults was recorded and samples of leaves and flowers were taken for identification at the Entomology - Acarology Laboratory of the National Center for Animal and Plant Health (CENSA). Of the adult samples analyzed in the laboratory, 83 5% belonged to the species M. usitatus. The cultivar 'Cul 156' showed the highest population density with 8,25 individuals per plant. The application of bioproducts, the tactics used at planting, and the times when both e-codaoleoK and the entomopathogenic nematodes were introduced facilitated achieving satisfactory yields. The best yields were obtained by the cultivar 'Triunfo 70', its shorter cycle allowed it to escape the pest damages. [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 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]

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]

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]