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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]

Studies on systems with multiple predatory species have shown that species interactions may not be predictable and are largely dependent on individual behavioral traits, species density, and habitat complexity. The interactions of the mirid predators Macrolophus basicornis (Stal) and Engytatus varians (Distant) (both Hemiptera: Miridae) with the pest Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) were examined, and the positive or negative effects of their combined use were estimated by a multiplicative risk model (MRM). The efficacy of single and mixed mirid species against eggs and larvae of the pest was estimated through 24-hours predation rates under laboratory conditions. Both mirid species preferred eggs and first instar larvae of T. absoluta. Their combined use was positive when their feeding was on these stages of the pest, but negative when it was on second instar larvae. Our results, based on predation rates, showed that M. basicornis had a higher predatory capacity than E. varians on first instar larvae of T. absoluta, but both mirids were good candidates as biocontrol agents against T. absoluta on tomato. [ABSTRACT FROM AUTHOR]

The objective of this work was to identify the speciments of the mealy bugs affecting plants of the potato (Solanum tuberosum L.) cultivars 'Atlas' and 'Rudolf' in the experimental plots of the Instituto de Investigaciones de Viandas Tropicales in the Province of Villa Clara, Cuba. These insects, distributed on stems and roots of the plants causing foliage chlorosis and root rot, were collected and taken to the Laboratory of Entomology of the Centro Nacional de Sanidad Agropecuaria to be studied. They were identified within the genus Pseudococcus and their presence in this province was reported for the first time. [ABSTRACT FROM AUTHOR]

In the present work, aspects of the duration of the embryonic and larval development of the granulated cutworm Feltia subterranea Fabricius are described. The first generation of larvae was found feeding on tomato seedlings (Solanum lycopersicum L.) at the "Las Piedras" farm in Guanabacoa, Havana, Cuba, in October 2017. For the insect rearing, larvae were transferred to the Entomology-Acarology laboratory of the National Center of Animal and Plant Health (CENSA). They were kept independently in mesh cages, and tomato seedlings of the angean variety were used for their feeding until the end of that phase. In the adult phase, females and males were independently mated and observed daily to determine the time that oviposition occurred and duration of this phase. Eggs deposited on the same day were used to determine the time taken by embryonic development, duration of the larval stage, and the number of larval stages. Embryonic development took 4 days. The eggs were always deposited in clusters on young plant leaves. The insect presented six larval stages and the larval period lasted 15 days. A gregarious behavior, more marked during the first instars, was observed during the larval phase. [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 biology and life table of two populations of Chloridea virescens F. were evaluated under laboratory conditions (T= 24.02 ± 0.24°C; HR= 82.52 ± 0.72%). Both populations differed in the morphological characteristic of the last instar larvae and the organ of the plant of tobacco from which they were collected. They were separated into two groups: Group A, larvae from the leaves of the plant head and Group B, larvae from the capsules. From these larvae, adults were obtained that mated and after the oviposition initiated, a cohort of recently emerged larvae of both groups was selected. They were disposed on leaves of tobacco to continue their development until adult death. In each group, the number of eggs per laying, the duration of the each development phase, and the main population parameters were recorded. The biological parameters showed significant differences in the larval and pupal duration and the life cycle that favored the specimens of the Group A, as in the population parameters. The results indicated that these parameters in the Group B population were affected by the change of food; however, a high reproductive capacity was evident in both groups when the specimens fed on leaves of the plant head, and the potentiality of both populations as pest of this crop was confirmed. [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]

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 aim of this work was to detect the presence of potyviruses in pepper plants (Capsicum annuum L.) with symptoms of mottling and in aphids associated with the crop in the main production areas of eastern, central, and western regions of Cuba by RT-PCR with generic primers. Total RNA was extracted and cDNA was synthesized from collected samples. The aphids were identified as Myzus persicae (Sulzer). Potyvirus detection was successfully achieved in the samples from the three regions, which indicated that they were widely distributed in the pepper production areas of the country. [ABSTRACT FROM AUTHOR]

Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae), well-known as pink hibiscus mealybug, constitutes a new species in the Neotropical region. It is associated to 73 plant families in more than 200 genera; thus it is considered as a highly polyphagous species. Due to the increasing importance from the reports on the economic impact caused in the Caribbean subregion, the damages and significant losses it has provoked, especially in Grenade Island and its quick dissemination in the area; a permanent surveillance should be established to prevent its possible introduction in our national territory. For such a reason, the present work constitutes another alternative in currently spreading the main characteristics of this exotic mealybug, which can be transformed into a potential danger for our agriculture. Also, the methods for its control are approached, making emphasis in the biological control and in some of the actions made by the country to delay and/or diminish introduction risks. [ABSTRACT FROM AUTHOR]

La planta de tabaco (Nicotiana tabacum L.) es afectada por varias especies de insectos plagas, dentro de ellos se destacan las larvas de lepidópteros. Tradicionalmente se ha determinado como Heliothis virescens (Fabricius), lo que en realidad constituye un complejo de especies, debido a que pueden confundirse fácilmente entre sí, ya que son semejantes en tamaño y coloración. El propósito del estudio fue determinar la presencia de las especies del complejo Heliothis en el tabaco cultivado al sol en la provincia Las Tunas, Cuba. Durante la pesquisa se utilizaron los adultos obtenidos de las recolecta de larvas realizadas en las parcelas experimentales de tres cultivares de tabaco (Habana-92, Habana-2000 e IT-2004), durante tres campañas tabacaleras. El empleo de claves dicotómicas y el desarrollo de los estudios de diseño alar, quetotaxia de 450 larvas y genitalia masculina de 280 adultos permitieron notificar, por primera vez en Cuba, la presencia de la especie Heliothis tergeminus (Felder y Rogenhofer) y constituye, además, el primer informe de la especie para el cultivo del tabaco en el país. [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]

In the laboratory (T = 24,02 ± 0,24°C; HR=82,52 ± 0,72%) and with different feeding, the cuticle color and ornamentation were determined in the last instar of Chloridea virescens Fab., from a cohort of 60 F1. Leaves of tobacco were used (main host), pigeon pea pods and rose petals (alternative hosts) were used for feeding. Duration of the larval phase and development, the sexual relationship, and the total natural mortality were taken into account. The results showed that C. virescens in tobacco had a wide phenotypic variability. Six coloration and ornamentation patterns, with a higher frequency of the yellowish coloration, were described on this host. The sister larvae feeding on rose and pigeon pea were grayish with a similar ornamentation; however, as a possible effect of the change of food, the mortality reported on these two host plants was higher than 50%. Nevertheless, the larvae completed the development cycle on the three hosts and showed a high morphological variability on tobacco; it was also confirmed that the population agreed with C. virescens. [ABSTRACT FROM AUTHOR]

The behavior of Lincus curvatus Campos & Roell and Macropygium reticulare (Fabricius) as possible vectors of the disease known as sudden wilt in the oil palm hybrid (Elaeis oleífera x Elaeis guineensis) was studied in the province of Orellana, Ecuador. The hosting site of both insects and those carrying flagellates were determined. Disease transmission with L. curvatus in 26-month-old crops and withM. reticulare in 4- and 8- year- old crops was also determined. The values within these determinations were compared by a multiple comparison analysis of proportions using the software Compapro Win 2.0. Of 1025 specimens collected, 76.98 % corresponded to L. curvatus and 23.02 % to M. reticulare. Of the specimens of L. curvatus, 80.48 % was found on the inflorescence peduncles and 19.52 % in the crop interlines; 100 % of M. reticulare was found only in the crop interlines. It was confirmed that 83. 40 % of Lincus sp. n. and 59.75 % of M. reticulare populations carried flagellates (Family: Tripanosomatidae). The disease transmission by both species was confirmed. With L. curvatus the symptoms were reproduced on 70.8 % of the plants evaluated, with the first case reported 27 days after the insects were deposited on the peduncle. With M. reticulare, the symptoms were reproduced in 25.0 % of the 4 year and in 16.67 % of the 8 year palms after 140 and 144 days, respectively, of being deposited the insects on the roots. [ABSTRACT FROM AUTHOR]

El artículo presenta un tesis de la autora sobre las cochinillas harinosas de Cuba. Discurre sobre la identificación de géneros y especies de las cochinillas, caracteres taxonómicos y información acerca de las observaciones realizadas por la autora. También se considera la biodiversidad de los insectos.

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]

Data obtained in studies on the biology and reproduction of Macrolophus basicornis (Heteroptera: Miridae) preying on Myzus persicae (Sulzer) and Macrosiphum euphorbiae (Thomas) on tomato at 28°C, were used to construct life tables for this polyphagous mirid. When M. euphorbiae was preying on M. persicae, the net reproductive rate (Ro) was 4.75, the intrinsic rate of increase (rm) 0.02 (hembra/hembra/day), the mean generation time (T) and the doubling time (DT) 73.91 and 32.9 days, respectively. The corresponding values when it was feeding on M. euphorbiae were 2.57, 0.01, 1.014 days and 49.35 days, respectively. The results demonstrated that M. basicornis could survive and reproduce with M. persicae as well as M. euphorbiae as preys, although the number of females obtained by generation will be smaller with M. euphorbiae. The number of females increased twice in front of M. persicae, what demonstrated that this latter prey had greater acceptance by the predator. [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]

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]

Plant hosts of Lincus curvatus Campos & Roell and Macropygium reticulare Fabricius and carriers of Phytomonas sp. surrounding the oil palm were studied in the states of Tripomastigote and Amastigote in the province of Orellana, Ecuador. It was set up a multifactorial split plot design with two blocks (High mortality-2.5 % and Low mortality-0.01 %), three plots (Inter palm lines, bordering area and jungle), and three sub-plots, in which the number of insects hosted per unit of plant species was evaluated. Twenty eight plant species classified within eighteen families were identified. L. curvatus was found in: Fabaceae, Marantaceae, Arecaceae, Heliconiaceae, Cyclanthaceae, Asteraceae, and Musaceae; M. reticulare was found in: Urticaceae, Asteraceae, Araceae, Commelinaceae, Arecaceae, Musaceae, Poaceae andFabaceae. The families reservoirs of Phytomonas sp. in the stated of Tripomastigote were: Euphorbiaceae and Arecaceae, while in the state of Amastigote were; Musaceae, Araceae, Alismataceae, Poaceae, Euphorbiaceae, Heliconiaceae, and Marantaceae. The highest population of L. curvatus was found in the jungle plot, while M. reticulare was found in the inter palm line plot. [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 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]

Con la creciente problemática de la enfermedad conocida como Marchitez Sorpresiva en el cultivo de Palma Aceitera en el Ecuador, y la tendencia al incremento de la producción agrícola con el uso de medios amigables al hombre y al ambiente para el manejo de plagas, se precisó buscar alternativas biológicas para el control del vector de esta enfermedad. Actualmente, las poblaciones del vector se controlan con insecticidas químicos, que eliminan al vector, la entomofauna natural, los enemigos naturales y polinizadores, entre otros. En campo se han recolectado cuatro cepas de hongos infectando el vector: Ophycordiceps sp., Beauveria bassiana, Paecilomyces sp. y Cordyceps sp. En el laboratorio se aisló, se cultivó y se evaluó la patogenicidad de estos mediante un diseño completamente aleatorizado; se probaron 2 dosis (CL50= 3,8 x 106; y 7,6 x 106 conidios ml-1), con 2 testigos comerciales y 3 repeticiones. La disolución y las mezclas se efectuaron en agua destilada; la variable respuesta fue la mortalidad del vector. Los resultados estadísticos demostraron que el entomopatógeno Paecilomyces tenuipes fue el más patogénico, la dosis 1 alcanzó el 83% y la 2 el 92% de mortalidad; el tiempo letal medio fue de TL50 = 12,7 y 13,0 días luego de la aplicación con la dosis 1 y 2, respectivamente. Las cepas subsiguientes no demostraron diferencia estadística significativa a las concentraciones probadas y el testigo químico presentó su efecto letal a las dosis probadas. [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]