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Objective: To assess malnutrition in elementary education students from four rural schools in the municipality of Paso de Ovejas, Veracruz, Mexico. Methodology: The study is based on the participatory action research process (PAR), a descriptive, analytical, non-experimental, and cross-sectional methodology. The body mass index (BMI) of 617 children and teenagers was measured through an anthropometric assessment. To determine malnutrition, the 2007 World Health Organization report which measures BMI according to gender and age was taken as reference. Results: Forty-seven percent of the students have a normal nutritional status. Among the rest of the student population, the problem of malnutrition is prevalent, with 43% being overweight or obese. Malnutrition in its three levels (mild, moderate, and severe) had an impact on 10% of the population, with girls being the most frequently affected. Implication: The study does not present dietary surveys nor students' medical histories. Still, anthropometry is a method validated by WHO. Findings: Nutritional problems --such as overweight, obesity, and malnutrition-- were observed in 53% of the students. Therefore, it is necessary to implement strategies that follow a participatory model and to develop a nutritional education program based on the "territorial food system". This will foster respect for the local culture and encourage the co-design of school and/or family kitchen gardens through agro-ecopedagogy. [ABSTRACT FROM AUTHOR]

This work analyzed the volatiles by obtaining extracts of green leaves of sugar cane in the mature state of eight varieties of sugarcane and of two pasture species by hydrodistillation with a Clevenger trap. The varieties of sugar cane used in this study were: CP 72-2086, MEX 69-290, RD 75-11, ITV 92-1424, MEX 79-431, L 77-50, COLPOS CT MEX 05-223, COLPOS CT MEX 05- 204. The grasses evaluated were: itchgrass (Rottboellia cochinchinensis) and African star grass (Cynodon nlemfuensis). In the evaluated material three main compounds were found, these are: (Z) -3-hexen-1-ol, 1-octen-3-ol and phytol. These compounds were more representative in the varieties CP 72-2086 and MEX 69-290. The compound with greater frequency was (Z) -3-hexen-1-ol, which was present in seven varieties as well as in the two pastures evaluated. The abundance of (Z) -3- hexen-1-ol in the samples of the varieties of sugarcane varies from 20.35% to 57.36%, the greater amount of (Z) -3-hexen-1-ol was detected in African star grass with an abundance of 59.69%. [ABSTRACT FROM AUTHOR]

• New suitability areas are expected across all CMIP6 model projections. • Future suitability areas move to northern and central regions. • Risk of diaphorina citri will probably increase in future scenarios. • Future projections indicate current suitability areas remain unchanged. Climate change may modify environmental conditions creating suitable environments for phytopathogen vectors in places that were not suitable before. The present study aimed to contrast current and future spatial distribution of Diaphorina citri in Mexico under two climate change scenarios, Shared Socioeconomic Pathways (SSP) 4.5 and 8.5 for years 2050 and 2070. Non-correlated bioclimatic variables from eight General Circulation Models derived from the Coupled Model Intercomparison Project-6 and presence point data were used to generate distribution models with MaxEnt. Future projections showed that current suitable areas, equivalent to a 38.6% of coverage persist across all scenarios, new suitability areas appear, and no reduction is expected. All the models coincide on a potential increase in relation to the current national distribution of 11.1, 14.8, 13.8 and 25.5% for SSP2 4.5–50 SSP2 4.5–70 SSP5 8.5–50, and SSP5 8.5–70 respectively. Most of the new areas are not currently dedicated to citriculture; however, an increase in the risk of Huanglongbing is expected because most of the new areas are contiguous to the current presence areas, and cover urban zones where there may exist rutaceous hosts, from which the vector may spread the disease to the production zones. [Display omitted] [ABSTRACT FROM AUTHOR]

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is an introduced pest in Mexico and a vector of huanglongbing, a lethal citrus disease. Estimations of the habitat distribution and population growth rates of D. citri are required to establish regional and areawide management strategies and can be used as a pest risk analysis tools. In this study, the habitat distribution of D. citri in Mexico was computed with MaxEnt, an inductive, machine-learning program that uses bioclimatic layers and point location data. Geographic distributions of development and population growth rates were determined by fitting a temperature-dependent, nonlinear model and projecting the rates over the target area, using the annual mean temperature as the predictor variable. The results showed that the most suitable regions for habitat of D. citri comprise the Gulf of Mexico states, Yucatán Peninsula, and areas scattered throughout the Pacific coastal states. Less suitable areas occurred in northern and central states. The most important predictor variables were related to temperature. Development and growth rates had a distribution wider than habitat, reaching some of the northern states of México. Habitat, development, and population growth rates were correlated to each other and with the citrus producing area. These relationships indicated that citrus producing states are within the most suitable regions for the occurrence, development, and population growth of D. citri, therefore increasing the risk of huanglongbing dispersion. [ABSTRACT FROM AUTHOR]

During sexual signaling, males of Anastrepha obliqua (Macquart) form leks and attract females by producing sounds and releasing volatile compounds. The objective of this study was to investigate the influence time of time of day, age, irradiation, mating status, and the presence of host fruit on the release of volatile components by laboratory-reared A. obliqua males. A. obliqua males released four compounds identified by gas chromatography coupled with mass spectrometry (CC- MS) as (E,E)-a-farnesene, (Z,E)-a-farnesene, (Z)-3-nonenol, and a farnesene isomer during calling behavior. Although males released volatiles during the entire day, the amount of volatiles was higher in the early morning and afternoon hours. Males began to emit volatiles when they were 6 d old, but only the amount of (Z) -3-nonenol was affected by age. Irradiation of flies with gamma rays from a 60Co source at a dose rate of 0.8 Gy significantly reduced the amount of volatiles released during calling behavior. The amount of volatiles was lower in recently mated males than virgin males. However, there were no significant differences between virgin males and males 24 h after mating. The presence of host fruit did not affect the amount of volatiles compared with the control. [ABSTRACT FROM AUTHOR]

Stenoma catenifer Walsingham is a quarantine pest of avocado. Therefore, its detection in avocado-growing regions of Mexico that had been designated pest-free can halt national and international trade. One option for monitoring S. catenifer is the use of synthetic sex pheromone traps. In this study we determined the optimal density of pheromone-baited traps for monitoring S. catenifer. The experiment was conducted in 4 commercial Hass avocado orchards in Colima, Mexico, each with different pest infestation levels. Trap densities were established at 0.5, 1, 2, or 3 traps per ha. The traps were checked every 15 d and the number of moths recorded. The density of 3 traps per ha captured the most moths per trap followed by 1 trap per ha; similar small numbers of moths were captured at densities of 0.5 and 2 traps per ha. In general, there was a linear relationship between trap catch and trap density per ha. The overall default error rate, i.e., the proportion of traps did not detect moths when they were present, was 5.5% at a density of 3 traps per ha and 2.7% at trap densities of 0.5 and 2 traps per ha. Furthermore, at a density of 1 trap per ha all traps captured moths and so there was no default error. Since S. catenifer is a quarantine pest that must be detected promptly to reduce the risk of dispersal and establishment in moth-free areas, it is suggested that a density of 1 trap per ha should be used in avocado orchards to effectively monitor for the presence of this pest. However, this estimate was obtained through the bootstrapping technique, which involves the creation of pseudoreplicate datasets by resampling. Randomized field experiments with true replicates are needed to corroborate this result. La presencia de Stenoma catenifer Walsingham, una plaga cuarentenaria, puede cancelar la comercialización nacional e internacional de aguacate Hass de zonas libres de plagas reglamentadas del aguacatero. Una opción para su oportuna detección es el uso de trampas con feromona sexual sintética. El objetivo del estudio fue determinar la densidad de estas de trampas para el monitoreo de S. catenifer. El experimento se estableció en cuatro huertos comerciales de aguacate Hass, con diferentes niveles de infestación de la plaga, en Colima, México. En los huertos, se establecieron las densidades siguientes: 0.5, 1, 2, y 3 trampas por ha. Las trampas se revisaron cada 15 días para registrar el número de palomillas capturadas. La densidad de 3 trampas por ha capturó el mayor número de palomillas, seguida de la densidad de 1 trampa por ha, mientras que las capturas con 0.5 y 2 trampas por ha fueron las menores, pero muy similares entre sí. En general, las densidades de 0.5, 1, y 2 trampas por ha en relación con la densidad de 3 trampas por ha estuvieron linealmente relacionadas en la mayoría de los casos. La tasa de error global por omisión, i.e., no detectar la palomilla cuando está presente, con referencia a la densidad de 3 trampas por ha fue de 5.5%, y de 2.7% para las densidades de 0.5 y 2 trampas por ha, mientras que en la densidad de 1 trampa por ha siempre se detectaron palomillas y no tuvo omisión de error. Por tratarse de una plaga de importancia cuarentenaria y por el interés de detectarla oportunamente y así reducir el riesgo de dispersión y establecimiento a las áreas libres, se sugiere usar la densidad de una trampa por hectárea de aguacate. Sin embargo, este estimado se obtuvo mediate la técnica de bootstrapping que utiliza pseudor-replicas. Para validar este resultado, se requieren experimentos de campo con repeticiones verdaderas. [ABSTRACT FROM AUTHOR]

The State of Veracruz in Mexico is one of the main cattle producers, and uses several veterinary products for disease and parasite control. For parasite control, ivermectin is one of the most frequently used substances. Nevertheless, even though previous research conducted in other countries has found that this product has negative effects on beneficial coprophagous fauna, no studies have described its effects on coprophagous insects at a local scale in Veracruz, Mexico. This study evaluated Euoniticellus intermedius survival, fecundity, fertility and preimaginal development under laboratory conditions when ivermectin was added to cattle dung at three different concentrations. The design included two controls (spiked dung), and the following product concentrations: 0.01, 1.0 and 100ppm, which were homogenized with wet cattle dung. 20 female-male E. intermedius couples between five and 15 days old were used and kept at 27°C, 70% RH, and 12h light for 10 days. The survival of all specimens, the fertility of 20 females and the gonadal maturity of 17 males were verified. The larval development in 162 pieces of brood-mass was examined, and a total of 974 larvae developed and reached adulthood. The highest ivermectin concentration was toxic at 1.0ppm dose, the survival of adults was reduced to almost the half, and at 100ppm, total mortality was observed. The effects on specimen reproductive systems showed that the ovary was not affected, that the testicle size increased, and that the fecundity and weight of brood-masses were reduced. Pre-imaginal development increased 0.5 times at 0.01ppm concentration, and the width of the cephalic capsule in third instar larvae diminished. The prolonging of development time may cause a phase lag in the field activity cycle, this lag may reduce the number of E. intermedius individuals and the efficiency of the environmental services that they provide [ABSTRACT FROM AUTHOR]

The State of Veracruz in Mexico is one of the main cattle producers, and uses several veterinary products for disease and parasite control. For parasite control, ivermectin is one of the most frequently used substances. Nevertheless, even though previous research conducted in other countries has found that this product has negative effects on beneficial coprophagous fauna, no studies have described its effects on coprophagous insects at a local scale in Veracruz, Mexico. This study evaluated Euoniticellus intermedius survival, fecundity, fertility and preimaginal development under laboratory conditions when ivermectin was added to cattle dung at three different concentrations. The design included two controls (spiked dung), and the following product concentrations: 0.01, 1.0 and 100ppm, which were homogenized with wet cattle dung. 20 female-male E. intermedius couples between five and 15 days old were used and kept at 27 degrees C, 70% RH, and 12h light for 10 days. The survival of all specimens, the fertility of 20 females and the gonadal maturity of 17 males were verified. The larval development in 162 pieces of brood-mass was examined, and a total of 974 larvae developed and reached adulthood. The highest ivermectin concentration was toxic at 1.0ppm dose, the survival of adults was reduced to almost the half, and at 100ppm, total mortality was observed. The effects on specimen reproductive systems showed that the ovary was not affected, that the testicle size increased, and that the fecundity and weight of brood-masses were reduced. Pre-imaginal development increased 0.5 times at 0.01ppm concentration, and the width of the cephalic capsule in third instar larvae diminished. The prolonging of development time may cause a phase lag in the field activity cycle, this lag may reduce the number of E. intermedius individuals and the efficiency of the environmental services that they provide.