Despite its economic, social, biological, and cultural importance, wild forms of the genus Phaseolus are not well represented in germplasm banks, and they are at great risk due to changes in land use as well as climate change. To improve our understanding of the potential geographical distribution of wild beans (Phaseolus spp.) from Mexico and support in situ and ex situ conservation programs, we determined the climatic adaptation ranges of 29 species and two subspecies of Phaseolus collected throughout Mexico. Based on five biotic and 117 abiotic variables obtained from different databases—WorldClim, Global‐Aridity, and Global‐PET—we performed principal component and cluster analyses. Germplasm was distributed among 12 climatic types from a possible 28. The general climatic ranges were as follows: 8–3,083 m above sea level; 12.07–26.96°C annual mean temperature; 10.33–202.68 mm annual precipitation; 9.33–16.56 W/m² of net radiation; 11.68–14.23 hr photoperiod; 0.06–1.57 aridity index; and 10–1,728 mm/month of annual potential evapotranspiration. Most descriptive variables (25) clustered species into two groups: One included germplasm from semihot climates, and the other included germplasm from temperate climates. Species clustering showed 45% to 54% coincidence with species previously grouped using molecular data. The species P. filiformis, P. purpusii, and P. maculatus were found at low‐humidity locations; these species could be used to improve our understanding of the extreme aridity adaptation mechanisms used by wild beans to avoid or tolerate climate change as well as to introgress favorable alleles into new cultivars adapted to hot, dry environments.

In Mexico, the tradition of consuming flowers dates to pre-Columbian times, and flower consumption persists today; however, this practice is typically unknown outside the regions where flowers are used in local gastronomy. The aim of this work was to evaluate the variation in polyphenol and flavonoid contents and antioxidant activity in inflorescence samples. Samples of izote (Yucca filifera), maguey pulquero (Agave salmiana), cuachepil or guachepil (Diphysa americana), and tepejilote or pacaya (Chamaedorea tepejilote) were collected from different communities and regions of Oaxaca, Mexico, during 2022. Specifically, ten to eleven inflorescence samples were collected per species, and their polyphenol and flavonoid contents and antioxidant activity were evaluated using UV–visible spectrophotometry and reference standards. Significant differences were detected between and within samples depending on their geographical origin (collection locations); the environment and site influenced the composition of the samples for each species. Across all species, significant and positive correlations of the polyphenol and flavonoid contents were identified with the antioxidant activity detected via the DPPH and FRAP methods. The high variability in phenolic compound contents and antioxidant activity within each species shows that the nutritional and nutraceutical potential of flowers may complement diets at the family and communitarian levels.

La patogénesis de Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. del estado de Michoacán, México se caracterizó en frutos de aguacatero (Persea americana L.) cultivar 'Hass'. El hongo causó los síntomas característicos de la enfermedad denominada 'antracnosis' a partir de los diez días después de la inoculación. La tasa de infección del hongo entre tratamientos fue significativamente diferente (p<0.05) a partir del sexto día de la inoculación y el desarrollo de la enfermedad se explicó por un modelo de regresión lineal simple (Y = 1.123 + 0.1133X). No se detectó la formación de apresorios pero sí la síntesis de una capa mucilaginosa asociada con los tubos germinativos. El proceso infectivo del hongo se manifestó con la penetración de las hifas intra e inter-celularmente y con la producción de acérvulos a partir de los 12 días después de la inoculación. Los síntomas de la antracnosis se asociaron con la degradación de polifenoles, plasmólisis, necrosis y desintegración celular.

Aspergillus species can produce aflatoxins (AFs), which can severely affect human and animal health. The objective was to evaluate the efficacy of reducing AF contamination of a non-aflatoxigenic isolate of A. flavus experimentally coinoculated with different aflatoxigenic strains in whole plant (WP), corn silage (CS), immature grains (IG) and in culture media (CM). An L-morphotype of A. flavus (CS1) was obtained from CS in a dairy farm located in the Mexican Highland Plateau; The CS1 failed to amplify the AFs biosynthetic pathway regulatory gene (aflR). Monosporic CS1 isolates were coinoculated in WP, CS, IG and CM, together with A. flavus strains with known aflatoxigenic capacity (originating from Cuautitlán and Tamaulipas, Mexico), and native isolates from concentrate feed (CF1, CF2 and CF3) and CS (CS2, CS3). AF production was evaluated by HPLC and fungal growth rate was measured on culture media. The positive control strains and those isolated from CF produced a large average amount of AFs (15,622 ± 3952 and 12,189 ± 3311 µg/kg), whereas A. flavus strains obtained from CS produced a lower AF concentration (126 ± 25.9 µg/kg). CS1 was efficient (p < 0.01) in decreasing AF concentrations when coinoculated together with CF, CS and aflatoxigenic positive control strains (71.6–88.7, 51.0–51.1 and 63.1–71.5%) on WP, CS, IG and CM substrates (73.9–78.2, 65.1–73.7, 63.8–68.4 and 57.4–67.6%). The results suggest that the non-aflatoxigenic isolate can be an effective tool to reduce AF contamination in feed and to minimize the presence of its metabolites in raw milk and dairy products intended for human nutrition.

Chromatin remodeling enzymes are important "writers", "readers" and "erasers" of the epigenetic code. These proteins are responsible for the placement, recognition, and removal of molecular marks in histone tails that trigger structural and functional changes in chromatin. This is also the case for histone deacetylases (HDACs), i.e., enzymes that remove acetyl groups from histone tails, signaling heterochromatin formation. Chromatin remodeling is necessary for cell differentiation processes in eukaryotes, and fungal pathogenesis in plants includes many adaptations to cause disease. Macrophomina phaseolina (Tassi) Goid. is a nonspecific, necrotrophic ascomycete phytopathogen that causes charcoal root disease. M. phaseolina is a frequent and highly destructive pathogen in crops such as common beans (Phaseolus vulgaris L.), particularly under both water and high temperature stresses. Here, we evaluated the effects of the classical HDAC inhibitor trichostatin A (TSA) on M. phaseolinain vitro growth and virulence. During inhibition assays, the growth of M. phaseolina in solid media, as well as the size of the microsclerotia, were reduced (p<0.05), and the colony morphology was remarkably affected. Under greenhouse experiments, treatment with TSA reduced (p<0.05) fungal virulence in common bean cv. BAT 477. Tests of LIPK, MAC1 and PMK1 gene expression during the interaction of fungi with BAT 477 revealed noticeable deregulation. Our results provide additional evidence about the role of HATs and HDACs in important biological processes of M. phaseolina.

The genus Salvia has a worldwide distribution, and its contribution to traditional medicine and as an aromatic plant has been recognized since ancient times, with few documented species having a similar phytochemical composition. In this study, the effects of natural growth conditions (in situ) and ex situ cultivation and sampling locations on the phenolic compound contents and antioxidant activity of methanolic extracts of Salvia circinata from Oaxaca, Mexico, were investigated. Stem and young leaf samples were collected from plants growing in situ in two locations in Oaxaca and later from plants propagated clonally or vegetatively from propagules obtained in situ but grown ex situ. In both sets of samples, the contents of total polyphenols and flavonoids and the antioxidant activity were evaluated by spectrophotometry, and subsequently, the contents of phenols and specific flavonoids were identified and quantified by high-performance liquid chromatography with diode-array detection (HPLC–DAD). The growth conditions and locality of origin of the samples significantly influenced the contents of total polyphenols and flavonoids and antioxidant activity, with the in situ conditions in the locality of Reforma, Oaxaca, favoring higher levels. Two phenolic acids (chlorogenic and rosmarinic) and two flavonoids (isoquercitrin and rutin) were identified, and the concentrations of these compounds were influenced by the growth conditions and localities of origin of the samples.