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The objective of this research was to identify the most promising formulation variants for entomopathogenic nematodes (EPNs) through a systematic review of the literature and a meta-analysis. The focus was aimed at preformulating a nematode strain of the Heterorhabditis genus. Thus, 81,900 articles within the period 1985-2022 were processed and 404 were selected for the review, of which only 44 were included in the database for the meta-analysis. Two databases were created: VIABILITY and PATHOGENICITY, with 254 and 224 pairs of data, respectively, after purification. The data were processed by the nematode genus (Heterorhabditis or Steinernema) according to the result of a generalized linear model to Proc Mixed of SAS 9.0 and the contrast test of minimal significant difference. The statistical package RStudio version 1.1.463 2018 was used for the meta-analytic study. The statistics Q and I² were evaluated. The effect size and its 95% confidence interval were calculated and a forest-plot graph was used. The meta-analysis showed a high variability of the viability and pathogenicity data. The results confirmed that the solid formulations by using clays and other excipients, were adequate to for the entomopathogenic nematodes of the genus Heterorhabditis. [ABSTRACT FROM AUTHOR]

The experiment was carried out at the farm La Amada, belonging to the Cooperativa de Creditos y Servicios Fortalecida Roberto Macías Gallego in Santiago de Cuba. The objective was to evaluate the effectiveness of applying Tabaquina, Oleonim or Heterorhabditis amazonensis on management of Bemisia tabaci populations and their influence on growth and productivity of beans (Phaseolus vulgaris L.), cultivar Velazco Largo). It was used a randomized block design with 4 treatments and 5 replications. The data obtained were processed in the R Commander statistical package by means of a simple variance analysis, applying Duncan's multi range test for p≥0.05. The results obtained showed the efficiency the treatments had in bean yield and pest population reduction, highlighting the treatment with entomopathogenic nematodes with 89% technical efficiency, reaching the crop a yield of 0.8 t / ha. [ABSTRACT FROM AUTHOR]

The effect of Steinernema rarum (Doucet) ((OLI) and N105 strains) from Córdoba province on the American cockroach Periplaneta americana (L.) was evaluated. Two doses: 3,200 and 6,400 infective juveniles (IJs) / host were used and a control group was considered. Forty-nine insects per treatment were evaluated. Infections were maintained at 25 ± 1 °C. Dead insects were recorded every 24 h during 15 days. Steinernema rarum (OLI) caused a mortality of 67% and 89%, for 3,200 and 6,400 JIs, respectively. With isolate N105, mortality never exceeded 65%. The two isolates completed their life cycle with the production and emergence of JIs in P. americana: for S. rarum (OLI), 255,215 ± 3 x 104 and 328,102 ± 3 x 104, for D3200 and D6400, respectively; for S. rarum N105, 142,451 ± 3 x 104 and 188,253 ± 3 x 104, D3200 and D6400, respectively. Significant differences between strains for the average number of JIs (F3,126 = 5,26; p = 0,001) were registered. Based on these results, Blattodea is incorporated into the range of hosts of S. rarum (OLI) and it is disclosed that P. americana is the first host for S. rarum N105 in laboratory. [ABSTRACT FROM AUTHOR]

In order to determine the biological control of Spodoptera frugiperda in the cultivation of corn with entomopathogenic nematodes, it was proposed to perform tests in the greenhouses of the National Agricultural Innovation Institute (INIA) using entomopathogenic nematodes (Heterorhabditis) with four different concentrations (200, 300, 500 and 750 juvenile infectives per treatment), which allowed us to determine the mean lethal concentration (LC50-48), percentage of mortality and damage in corn plants by the cogollero. The 95% Probit analysis showed that the LC50-48 for H. bacteriophora was 182.58 Ijs / larva and for H. sp (native), it was 262.68 Ijs / larva. The Anova test and the simultaneous comparison of Tuckey found significant differences (p = 0.005) between some concentrations of the treatments, establishing that the best nematode to fight the larvae of the bud was H. bacteriophora, with the lowest percentage of damage in the plant (53.33%) and the highest mortality (84.44%) at a concentration of 750 Ijs / larva. Compared to the treatment with H. sp (native), which obtained a higher percentage of plant damage (83.33%) and the lowest mortality (46.66%) at a concentration of 200 Ijs / larva. [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]

The spittlebug or froghopper is an important pest of sugarcane that encompasses a complex of species in the genera Aeneolamia and Prosapia (Hemiptera: Cercopidae). Control of these insects is carried out with chemical insecticides; however, effective control is not always achieved. Also, entomopathogenic fungi, such as Metarhizium anisopliae, have been applied, and the use of entomopathogenic nematodes (EPN) has been proposed. In this study, we assessed the field virulence of two native strains, Steinernema sp. CP13ES (group IV, bicornutum-certophorum-riobrave) and Heterorhabditis indica CP13JA, collected from sugarcane fields of Constancia and La Gloria sugarcane mills in Veracruz, Mexico. Field trials were conducted in two areas of these sugarcane mills. Both strains were mixed with the adjuvant Break-Thru® and were sprayed in sugarcane plots infested with spittlebug nymphs. In the first trial, we tested the efficacy of the two EPN strains in conjunction with a dispersant agent to select the most appropriate strain. In the second trial, we evaluated Steinernema sp. strain considering 1-m2 field plots. Results from trial 1 showed that both strains were significantly similar (P > 0.05) in their virulence: H. indica, recorded 73% mortality and Steinernema sp. 62%. Results from trial 2 demonstrated that the Steinernema strain was able to maintain a significantly lower (P = 0.25) spittlebug population for 4 days when compared to the control, whereas the nymph populations doubled during the same time period. These studies show the potential of the native EPN for field control of spittlebug nymphs in Mexico. [ABSTRACT FROM AUTHOR]

Hypothenemus hampei Ferrari, coffee berry borer is considered the pest that bigger causes damage, to coffee production all over the world. It is an insect of difficult handling with the traditional control methods by mean of insecticides. For this reason the Strategy of Integrated Handling of this Plague take into consideration since manual collection of the insect up the employment of biological controls. The last alternative is one of the more appealed by coffee farmers due to the minor cost. That's why with the realization of this work the levels of effectiveness of several doses of Heterorhabditis bacteriophora on the control of H. hampei were evaluated. There were not significant differences between the three doses evaluated so it is suggested the employment of the dose of 500 million for hectare for the control of the plague because it is the most economic dose. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the molecular variability in a collection of Venezuelan isolates of entomopathogenic nematodes and their symbiont bacteria through the application of RAPD markers. The DNA of nematodes and bacteria were extracted by a modification of the method described by Salazar et al. RAPD assay was developed with the primers from the kits OPA and OPB. Genetic fingerprinting of isolates of the nematode and symbiotic bacteria were determined. The total amplified bands for nematode was 493 and 496 for bacteria, with 99,18 and 100% polymorphism, respectively. The clustering obtained for the nematodes was related to the altitude above the sea level at which they were collected, while for the bacteria, the clustering was in general related to the type of soil from which they came. [ABSTRACT FROM AUTHOR]

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A breeding of S. frugiperda were took, the nematode employee was Heterorhabditis indica Poinar strain P2M that this distributed by all Cuba and is reproduces on Galleria mellonella L. Larvae of 3rd, 4th and 5th instars of the insect were used for the trial, recognized through the diameter of their cephalic cap. 12 larva for instars were taken for each concentrations of 250 n/larva and 500 n/larva. The evaluations started at 24 hours after the inoculation until 72 hours. The same quantity of larva were used as control with sterile water. Changes of the original larva exoskeleton coloration (brown, brown yellow and brown dark) and the consistency of the body of the larva once parasiteds and died by the action of the nematode (F: Flabby; M: Mummified; C.H: Moisturized Body) were determined. The treatments were compared to determine the best inoculation concentration and the best instars to reproduce the entomopathogenic nematode. The 5th instars for the reproduction of the NEPs was the more effective of S. frugiperda, with an increment of 47.194 and 171.7 times for the doses of inoculation of 250 n/larva and 500 n/larva. Larvae of the 3rd and 4th instars of S. frugiperda mummified starting from the 5th day of inoculated, which allows that they can be mounted in White to the sixth day post-inoculation. [ABSTRACT FROM AUTHOR]

Metamasius hemipterus sericeus (L.) is one of the most damaging insect cause to crops of bananas and plantains. Their control is limited to the employment of chemical products that are introduced in the soil where it inhabits. A possible means of control on this insect constitutes the entomopathogenic nematodes. Susceptibility of M. hemipterus sericeus L. was determined to the native strain CIAP-DEY-6 of Heterorhabditis sp. The insects were collected in fields of bananas during the months of December 2007 to May of the 2008 and subjected to a period of quarantine and fed with banana pseudostem. The experiments were carried out in the laboratory of Pathology of Insects of the Center of Agricultural Researchs (CIAP). They were placed (5 individuals) in Petri dishes of 18 cm diameter on a filter paper and inoculated with 10 000 nematodes/mL; being applied 3 mL by each dish. They were evaluated to the 5 and 10 days after the application. It had 20 replicates and a control. Underwent necropsy at 30% of the cadavers and verified the penetration of the juvenile infective. The traps type canoe captured 96.28% of M. hemipterus. The adults of M. hemipterus sericeus are susceptible to the native strain of entomopathogenic nematode CIAP-DEY-6. At 10 days killed to 100% of the adults of M. hemipterus sericeus. [ABSTRACT FROM AUTHOR]

The strain HC1 belonging to Heterorhabditis bacteriophora has shown to be an effective biological control agent for important pests in Cuba, showing also potentialities for coffee berry borer (CBB) management. The objective of this work was to study the relationship between this organism and Beauveria bassiana, fungi with high use at international scale for CBB under field conditions and with the Thiodan, pesticide for this purpose. The strain HC1 of H. bacteriophora showed a synergic and additive effect, with a 62% mortality in the treatment with two biocontrol organisms. In the Petri dish viability assay, using infective juveniles of nematodes (HC1) and Endosulfan (Thiodan), the 97-98% of juveniles survived during almost 36h in pesticide solution, with similar values to distilled water. The pesticide neither affected the nematode pathogenicity, which caused a 100% mortality in Corcyra cephalonica larvae and Ips sp. adults, independently the exposition time to the pesticide. The assays carried out in this work confirm the possibility to use H. bacteriophora HC1 and Thiodan in simultaneous applications, as well as the use of HC1 - B. bassiana, element of great importance for the management of this pest in coffee agroecosystems, since in the case of having high insect densities, they can be applied together. [ABSTRACT FROM AUTHOR]

In "Las Celias" organoponic, among the months of January of the 2003 to June of the 2004, for two years they were carried out 7 treatments, with entomopathogenic nematode for control Diaphania hyalinata (L.) (Lepidoptera; Pyralidae) in cucumber crop (Cucumis sativus L.). In this system the cucumber was intercrop with Beta vulgaris L. and Lactuca sativa L. They were sowed of cucumber (Cucumis sativus L.), cameras of 78,33 m2, Beta vulgaris L., always was associated with the main crop. In the second year it was inserted with Lactuca sativa L. The entomopathogenic nematode showed a very good biological effective under organopónicos conditions to control D. hyalinata, although they didn't carry out a control on the egg of this pest. The treatments of better yields of cucumber were P2M and CIAP-DEY-6 respectively with 1,18 and 1,16 kg/m2. In the second year these yields went superior to the 2 kg/m2. The biological treatments didn't present significant differences among them but were with chemists treatments. The biodiversity in the system was increased in the second year of field the cultivation as a result of the decrease of chemical applications. It is feasible economically the employment of nematodes in the control of this pest. [ABSTRACT FROM AUTHOR]