This study aimed to determine the population fluctuation of Scolytinae (Coleoptera: Curculionidae) in orchards of avocado Persea americana var. Hass, located in the municipalities of Nuevo San Juan Parangaricutiro (SJ), Uruapan (UR), and Ziracuaretiro (ZR), Michoacán, México. The study was carried out from July 2016 to June 2018. The insects were captured using a-copaene, ethanol and querciverol + ethanol lures, which were placed in bottle traps. The population fluctuation of Scolytinae, during both years and sampling sites, presented its maximum peak during July and August. In ZR, the highest abundance of Scolytinae were recorded during July and October in the 2016-2017 cycle, and during September and October in the 2017-2018 cycle. The population abundance of Scolytinae was higher during the 2016-2017 cycle in SJ and UR, and in ZR the highest population abundance corresponded to the 2017-2018 cycle. The most abundant species of Scolytinae in SJ were Microcorthylus invalidus (43.28%), Araptus schwarzi (28.68 %) and Corthylus detrimentosus (23.02 %), in UR, were A. schwarzi (41.40%) and M. invalidus (14.75%) and ZR were Premnobius cavipennis (26.04%), Hypothenemus crudiae (17.75 %) and Corthylus flagellifer (16.17%). At the three sites, the maximum population coincided with the periods with higher rainfall and higher relative humidity percentages, conditions that favored a greater availability of food resources at the sites, which were used by the species for their establishment.

This is the first report of Cactophagus spinolae feeding and causing damage to the stem, vascular fleshy tissue, flower bud and fruit of pitahaya (Selenicereus undatus) plants in the urban area of the state of Guerrero, Mexico.

Background: Mexico is the seventh largest producer of jamaica in the world, Guerrero represents the entity with the largest area planted and produces >60% of the country's jamaica. The crop has numerous phytosanitary limitations, among which the chalice staining associated with a fungal complex stands out. The main damage occurs in flowering, reporting losses of 50 to 100% in areas without adequate phytosanitary management. The use of strains of Trichoderma spp. with antagonistic capacity, it represents a viable ecological alternative for the ecological management of the disease. Objective: to identify native strains of Trichoderma spp. and to evaluate its antagonistic capacity in vitro on important phytopathogenic fungi in the cultivation of hibiscus. Methodology: the research was developed in the 2018-2019 cycle in the Microbiology Laboratory of the Faculty of Agricultural and Environmental Sciences of University of Guerrero, Iguala, Guerrero. Systematic soil samplings were carried out in jamaica producing areas in Tecoanapa, Guerrero. The isolates were obtained by serial decimal dilutions and consecutive re-isolates until obtaining pure monosporic colonies. The isolates generated were identified morphologically and molecularly. The antagonistic capacity in vitro of each Trichoderma isolate was evaluated against purified monosporic strains of Phytophthora parasitica, Fusarium oxysporum, Corynespora cassicola and Coniella diplodiella. A completely randomized design was established with four repetitions per interaction, an analysis of variances and multiple comparison of means (Tukey, p <0.05) of the variables was performed: percentage of radial growth inhibition (PICR), days until first contact between hyphae (DCH) and area of intersection. Four isolates of Trichoderma spp. with particular morphological and growth characteristics. Results: with the help of the keys of Barnett and Hunter (1998) and Samuels (2006), and the sequences resulting from the molecular tests, it was possible to identify with 99% similarity to T. virens and T. longibrachiatum as Trichoderma species dominant in soils of jamaica producing areas of Guerrero. The results indicated that all the isolates significantly reduced the size of the colonies of the phytopathogens; the Tl4 isolates consistently presented the highest PICRs (75-95%); Phytophthora parasitica was the organism for the most part, and Coniella diplodiella presented the greatest resistance to invasion by antagonist agents. Isolate Tl4 was identified as the one that most inhibited the development of all pathogenic agents (89.25%). In dual confrontations, the hyphae of both microorganisms made contact at 3.25 days after sowing on average. Isolate Tl4 (T. longibrachiatum) was identified as the one with the highest levels of interaction zone and based on the linear regression analysis and Pearson's correlation coefficient, a wide relationship between the zone area of interaction and the percentage of inhibition of the control agents. Implications: It is proposed to continue the study in the field phase, incorporating what was obtained in an integrated pest management (IPM) system. Conclusions: these results contribute to the agronomic management of jamaica in the region as a precedent in the search for alternatives for managing diseases with low environmental impact, also contributing to the determination of the etiology of the disease.

El objetivo de la investigación fue identificar las familias de ácaros asociados a zarzamora silvestre (Rubus fruticosus L.), conocer su distribución espacial y su fluctuación poblacional en la localidad de Telcruz, ubicada en el municipio de Cuautitlán de García Barragán en el estado de Jalisco, México. Se colectaron 1.836 ácaros correspondientes a tres órdenes y 14 familias, de las cuales las más abundantes son Tetranychidae, Diptilomiopidae, Eriophyidae y Phytoseiidae, que aportaron el 73,6% del total de los ácaros. Las familias Parasitidae, Bdellidae, Cunaxidae, Iolinidae, Oribatidae son nuevos registros de asociación a plantas de zarzamora silvestre en México. La mayor parte de las familias se distribuyeron en el estrato medio de las plantas. La fluctuación poblacional aumentó a partir de febrero, con el pico más alto en abril. Se observó que el número de familias depredadoras aumentó en la medida en que se incrementó el de familias fitófagas. Este es el primer estudio donde se realiza un inventario de las familias de ácaros asociados a plantas silvestres de zarzamora y que sirve como un antecedente para futuras investigaciones acerca de cómo emplear estrategias de manejo más efectivas en este cultivo.

Tomato is one of the most consumed vegetables per capita in the world; it is grown both in the open and in greenhouses. Under these conditions, the pest is considered a severe problem, especially considering Bactericera cockerelli Sulc. Therefore, in this experiment, the life history of this pest insect in two tomato varieties: “Charanda F1” and “Rafaello” the differences in the development stages of the insect, the mean temperatures of two cycles, and the accumulated heat units determined. The work consisted of evaluating the development of the instars of B. cockerelli during two crop cycles in both varieties, as well as the accumulation of heat units to differentiate the distinct instars. The insect populations developed in the Rafaello variety had shorter lives and showed a higher death rate of eggs than did those that developed in Charanda F1. The temperature was another determining factor; when the temperature remained low, the insect biological cycle was longer. Likewise, heat units were different between the two varieties; in Rafaello, 598.13 heat units needed while in Charanda F1, only 464.98. The differences may be due to the morphological characteristics of each variety, as the presence of trichomes and oils. Thus, we suggest that these variables studied in future research works.

The cactus Selenicereus undatus (S. undatus), known as pitahaya or dragon fruit, is one of the pitaya species of economic importance for different countries worldwide, particularly in China, Mexico, Australia, Vietnam, Indonesia, and the United States, among other countries. On the other hand, Cactophagus spinolae (C. spinolae) is a pest insect found in Mexico, known as the cactus weevil or borer. This study reports, for the first time, C. spinolae feeding and damage to the vascular stem and flower bud of wild S. undatus plants in Jalisco, Mexico. Field sampling was conducted in wild populations of S. undatus between July and October 2024. The results of our study confirm that C. spinolae actively feeds on S. undatus, causing damage to the plant, primarily to the vascular cylinder of mature and immature stems, as well as to flower buds and tissues. During monitoring, we observed a total of nine eggs, nine larvae, and sixteen adults in different plant samples, confirming that S. undatus serves as a reproductive host for C. spinolae. The results highlight the threat of C. spinolae to S. undatus in the State of Jalisco, which highlights the need to incorporate new agricultural strategies to mitigate the impact that this insect has on pitahaya.