This review deals with the main mechanisms of action exerted by antagonistic bacteria, such as competition for space and nutrients, suppression via siderophores, hydrolytic enzymes, antibiosis, biofilm formation, and induction of plant resistance. These mechanisms inhibit phytopathogen growth that affects postharvest fruit since quality and safety parameters are influenced by the action of these microorganisms, which cause production losses in more than 50% of fruit tree species. The use of synthetic fungicide products has been the dominant control strategy for diseases caused by fungi. However, their excessive and inappropriate use in intensive agriculture has brought about problems that have led to environmental contamination, considerable residues in agricultural products, and phytopathogen resistance. Thus, there is a need to generate alternatives that are safe, ecological, and economically viable to face this problem. Phytopathogen inhibition in fruit utilizing antagonist microorganisms has been recognized as a type of biological control (BC), which could represent a viable and environmentally safe alternative to synthetic fungicides. Despite the ecological benefit that derives from the use of controllers and biological control agents (BCA) at a commercial level, their application and efficient use has been minimal at a global level.

Coffee farming in Mexico is an activity of great economic, social, cultural, and environmental importance. One of the strategies for obtaining better prices is so-called "specialty coffees", whose quality is evaluated through the "cup of excellence" contest. The aim of this work was to identify if there are factors related to the quality of coffee, based on the data provided by this contest. Information was obtained for the period 2012 to 2019 (since the event was suspended in 2020), but given the heterogeneity in the data, exclusion, and inclusion criteria were applied, examining only the years 2017 to 2019. Descriptive analyses show that, in Mexico, the coffee producing states of Veracruz and Chiapas predominate the highest scores, possibly because they are regions with the highest presence of biodiversity, which favors the quality of the coffee. A simple linear regression model also noted that quantitative variables (altitude, temperature, and precipitation) do not affect cup quality. Finally, a square chi analysis showed that the factors that affect the score are the process and mixing of varieties, which establish differences in the sensory characteristics of coffee, observing dependence between the two. It is concluded that the latter influence the score, where the washing process is best suited for coffees with an extraordinary quality profile, as well as the use of one or three varieties (particularly Arabica type) and that environmental and site components do not have a decisive effect on coffee cup quality.

For years, the presence of clubroot disease and its causal agent, Plasmodiophora brassicae, in Mexico has been stated as a fact. However, an intensive search of the scientific literature in English and Spanish, as well as grey literature including thesis and government reports, did not reveal any information about the actual detection of the pathogen, affected hosts, or areas with clubroot presence, or any information about clubroot (‘hernia de la col’, in Mexico). To confirm if P. brassicae was indeed in Mexico, we started a true detective adventure. First, we identified agricultural communities with a history of cruciferous crop cultivation. Secondly, we interviewed growers if they did see clubroot on their crops using pictures of the characteristic root galls. Thirdly, we collected soil from the locations with reported presence of clubroot and looked for the presence of clubroot/P. brassicae in the soil using several cruciferous bait plants. For the very first time we confirm the presence of the clubroot pathogen P. brassicae in Mexico, through a bioassay, the presence of resting spores and a P. brassicae specific PCR assay. The identification of P. brassicae in Mexico, will contribute to understand the genetic diversity of this elusive and devastating plant pathogen in future studies.

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Introducción. La vainilla se cultiva en agreoecosistemas bajo diversa intensidad de manejo, con características ambientales particulares que podrían ser desfavorables para la orquídea. Las condiciones atmosféricas son importantes, debido al cambio climático. Objetivo. Caracterizar las condiciones climáticas y microclimáticas de tres sistemas productivos de vainilla (Vanilla planifolia Jacks. ex Andrews). Materiales y métodos. El estudio se realizó en tres sistemas productivos de vainilla ubicados en Veracruz y Oaxaca, México. Se utilizaron tres intensidades de manejo: a) acahual, bajo sombra de diversas especies arbóreas; b) monocultivo, intercalado con una especie arbórea y c) malla sombra (con sombra artificial). Se abarcó un año de monitoreo (diciembre-2020 a noviembre-2021), que incluyó cuatro temporadas climáticas, dos frías y dos cálidas. Se midieron variables climáticas (de la región) y microclimáticas (de la parcela): temperatura (T), humedad relativa (HR) y radiación fotosintéticamente activa (RFA, solo en el microclima), con estaciones automatizadas; además se calculó el déficit de presión de vapor (DPV). Resultados. A escala diaria, las condiciones climáticas como microclimáticas en el acahual fueron más favorables para el cultivo de vainilla en las cuatro temporadas evaluadas; el monocultivo y la malla sombra experimentaron condiciones de humedad y temperatura fuera de los requerimientos agroclimáticos de la vainilla, principalmente en marzo-mayo (MAM), con Tmax >32 °C y HR <80 %. A escala horaria, las condiciones más cálidas y secas estuvieron en el monocultivo y la malla sombra en diciembre-febrero (DEF) y MAM; mientras que en junio-agosto (JJA) y septiembre-noviembre (SON) en acahual y malla sombra; el DPV (>2 kPa) indicó periodos más prolongados de estrés hídrico en estos sistemas. Conclusiones. El monocultivo y la malla sombra presentaron condiciones de humedad y temperatura desfavorables para la vainilla, con más periodos de estrés hídrico. El acahual presentó las condiciones climáticas y microclimáticas más convenientes para el cultivo de vainilla.