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Isaria fumosorosea is an entomopathogenic fungus that is used as a control alternative for nymphs and adults of Bemisia tabaci. Currently there are some commercial products, however, in greenhouse or field, these do not reach the levels of control as in the laboratory because the viability of the spores decreases as a result of the conditions of application of these products in situ. The objective of this work is to implement, through agroecological data, a system of biotechnological traps based on I. fumosorosea to increase the control efficiency mainly of adults of B. tabaci in strawberry greenhouses. One way to quantify the degree of infestation of a crop is the use of yellow traps, likewise to determine the spatial distribution of adults. The Taylor method [(1984). Assessing and interpreting the spatial distributions of insect populations. Annual Reviews of Entomology, 29, 321-357) was used in five different strawberry cultivation models, finding aggregate and regular distributions. Finally, once the crop model with the highest degree of infestation was selected, the designed traps were tested and mortalities were obtained between 50% and 90% in both the laboratory and the greenhouse. The biotechnological traps based on I. fumosorosea both in the laboratory and in the greenhouse had statistically the same effect as those used under the traditional method used in the field that is aspersion; therefore, this alternative method of application can be a tool important for the biological control of this pest. [ABSTRACT FROM AUTHOR]

Mexico is the third producer of strawberry (Fragaria ananassa Duchesne) in the world after the USA and China. However, year after year the strawberry crops suffer from large economic losses due to the incidence of insect pests. It should be mentioned that one of the most harmful pests for strawberry and most crops is Bemisia tabaci (Gennadius). Insecticides have been the most used products in strawberry, however, due to irrational use, resistance has been detected to some chemical compounds in the populations of B. tabaci. Application of biological control agents is an alternative to reduce this problem. In this work the interaction of Bacillus thuringiensis strain GP139 and Beauveria bassiana strain HPI-019/14 was evaluated for the biological control of B. tabaci nymphs in strawberry crop under laboratory and greenhouse conditions. The interaction between B. thuringiensis and B. bassiana showed to have an antagonist effect and mortalities below 70% for laboratory conditions and 50% for greenhouse conditions at low and medium concentrations of conidia (1 × 101 and 1 × 106 conidia / mL) and maintaining the constant concentration of total protein 40 μg / mL. At higher concentrations of conidia (1 × 107 and 1 × 108 conidia / mL) and maintaining the constant concentration of total protein 40 μg / mL the mortality increase above 90% for both conditions (laboratory and greenhouse) also observing an additive effect. It showed considerable potential for the use of B. thuringiensis and B. bassiana as key elements of an integrated pest management multi-component system for B. tabaci management. Clearly, programs like this have a great potential also to reduce selection pressures and development of resistance. [ABSTRACT FROM AUTHOR]

Parasitic agents, such as helminths, are the most important biotic factors affecting aquaculture, and the fluke Centrocestus formosanus is considered to be highly pathogenic in various fish species. There have been efforts to control this parasite with chemical helminthicides, but these efforts have had unsuccessful results. We evaluated the anthelmintic effect of 37 strains of Bacillus thuringiensis against C. formosanus metacercariae in vitro using two concentrations of total protein, and only six strains produced high mortality. The virulence (CL50) on matacercariae of three strains was obtained: the GP308, GP526, and ME1 strains exhibited a LC50 of 146.2 μg/mL, 289.2 μg/mL, and 1721.9 μg/mL, respectively. Additionally, these six B. thuringiensis strains were evaluated against the cercariae of C. formosanus; the LC50 obtained from the GP526 strain with solubilized protein was 83.8 μg/mL, and it could be considered as an alternative control of the metacercariae and cercariae of this parasite in the productivity systems of ornamental fishes. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis is a gram-positive soil-dwelling bacterium that is commonly used as a biological pesticide. This bacterium may also be used for biological control of helminth parasites in domestic animals. In this study, we evaluated the possible ovicidal and cestocidal effects of a total protein extract of B. thuringiensis native strains on the zoonotic cestode parasite of dogs, Dipylidium caninum (D. caninum). Dose and time response curves were determined by coincubating B. thuringiensis proteins at concentration ranging from 100 to 1000 μg/mL along with 4000 egg capsules of D. caninum. Egg viability was evaluated using the trypan blue exclusion test. The lethal concentration of toxins on eggs was 600 μg/ml, and the best incubation time to produce this effect was 3 h. In the adult stage, the motility and the thickness of the tegument were used as indicators of damage. The motility was inhibited by 100% after 8 hours of culture compared to the control group, while the thickness of the cestode was reduced by 34%. Conclusively, proteins of the strain GP526 of B. thuringiensis directly act upon D. caninum showing ovicidal and cestocidal effects. Thus, B. thuringiensis is proposed as a potential biological control agent against this zoonosis. [ABSTRACT FROM AUTHOR]

Aethina tumida is a pest from Africa, and has become an emerging threat to the health of bee hives outside of its endemic area. In 2007, it was reported for the first time in Mexico in the northern state of Coahuila. Later it would be confirmed in several Mexican states. In January 2023 in an apiary at the Municipality of Iguala in the Mexican state of Guerrero, a routine inspection by beekeepers revealed the presence of adults of A. tumida inside the managed colonies of Apis mellifera. This is the first report of the arrival of A. tumida to the State of Guerrero. The uncontrollable spread of A. tumida through beekeeping regions of Mexico becomes a threat to honey bee and wild bee hives. Aethina tumida es una plaga de África, y se ha convertido en una amenaza emergente para la salud de las colmenas de abejas fuera de su área endémica. En el 2007, se reportó por primera vez en México en el estado norteño de Coahuila. Posteriormente, sería confirmada su presencia en varios estados de México. En enero del 2023, en un apiario del municipio de Iguala del estado de Guerrero, una inspección de rutina realizada por apicultores reveló la presencia de adultos de A. tumida en colmenas de Apis mellifera. Este es el primer reporte de la llegada de A. tumida al estado de Guerrero. La incontrolable propagación de A. tumida a través de las regiones apícolas de México se convierte en una amenaza para las colmenas de abejas melíferas y silvestres. [ABSTRACT FROM AUTHOR]

En junio 2018 la escama Praelongorthezia acapulcoa (Ortheziidae) se presentó en altas poblaciones en campos de arroz en Morelos, México, primer reporte en este cultivo. Su biología y hábitos son similares a los presentados en caña de azúcar. In June of 2018 a scale of the Ortheziidae family was present in high densities in rice fields in Morelos, Mexico. This insect was identified as Praelongorthezia acapulcoa (Morrison), 1952 , which has not previously been reported in rice fields. Its biology and habits are similar to those that presents in sugarcane. [ABSTRACT FROM AUTHOR]

Meccus pallidipennis Stål is a vector for Chagas disease. The extensive use of pyrethroid insecticides to control triatomines in Mexico has resulted in the development of resistant populations. As an alternative control approach, the effects on M. pallidipennis eggs of two entomopathogenic fungi, Isaria fumosorosea Wize (Hypocreales: Cordycipitaceae) EH-511/3 and Metarhizium anisopliae (Metschn.) Sorokin (Hypocreales: Clavicipitaceae) EH-473/4, were examined. Egg mortality was estimated 1 mo after egg infection, based on hyphal growth and unsuccessful hatching as proxies for infection and death. Sporulation and conidial production rates were also recorded. Mortality rates caused by I. fumosorosea and Me. anisopliae were 92% ± 3.1 and 88% ± 3.7, respectively. Sporulation rate and conidial production were greater in I. fumosorosea than in Me. anisopliae. Transmission electron microscopy revealed hyphal penetration by both fungal species and damage to embryonic epidermal and cuticular cells. Our results demonstrated that I. fumosorosea and Me. anisopliae are promising candidates for controlling M. pallidipennis eggs and offer alternatives to control the transmission of Chagas disease under natural conditions.