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We assessed inter-seasonal dynamics of seed banks, dormancy and seed germination in three endemic Chihuahuan Desert succulent species, under simulated soil warming conditions. Hexagonal open top-chambers (OTCs) were used to increase soil temperature. Seeds of Echinocactus platyacanthus (Cactaceae), Yucca filifera and Agave striata (Asparagaceae) were collected and buried within and outside OTCs. During the course of one year, at the end of each season, seed batches were exhumed to test viability and germination. Soil temperature in OTCs was higher than in control plots. Yucca filifera seeds always had high germination independently of warming treatment and season. Agave striata seeds from OTCs had higher germination than those from control plots. Agave striata exhibited low germination in fresh seeds, but high germination in spring. Seeds from this species lost viability throughout the experimental timeframe, and had no viable seeds remaining in the soil. Echinocactus platyacanthus showed high germination in fresh seeds and displayed dormancy cycling, leading to high germination in spring, low germination in summer and autumn, and high germination in winter. Germination of this species was also higher in seeds from OTCs than those from control plots. Echinocactus platyacanthus formed soil seed banks and its cycle of inter-seasonal dormancy/germination could be an efficient physiological mechanism in a climate change scenario. Under global warming projections, our results suggest that future temperatures may still fall within the three studied species’ thermal germination range. However, higher germination for A. striata and E. platyacanthus at warmer temperatures may reduce the number of seeds retained in the seed bank, and this could be interpreted as limiting their ability to spread risk over time. This is the first experimental study projecting an increase in soil temperature to assess population traits of succulent plants under a climate change scenario for American deserts.

Human‐induced warming may increase the risk of local extinction for plant species with low tolerance of elevated temperatures. The Chihuahuan desert harbors the highest diversity of globose cacti in the world and most of them are at risk of extinction. Predictive models of climate change indicate an increase in summer temperature of 1–2°C by 2030 for this desert. Nevertheless, studies on the vulnerability of cacti species in early development phases to future climate change are scarce. We assessed the survival of three threatened cacti species from the Chihuahuan desert under induced warming. Open‐top chambers (OTCs) were used to simulate the effect of global warming on 2‐year seedlings of Echinocactus platyacanthus f. visnaga, Ferocactus histrix and Stenocactus coptonogonus. OTCs had higher temperature and lower humidity than control plots, and these elevated temperatures reduced seedling survival. Within the OTCs, no living individuals of any species were found after 105 days. Conversely, in the control plots, the three cacti species showed variable numbers of survivors after this period. Therefore the predicted global warming scenarios will greatly limit plant recruitment and the long‐term persistence of natural populations of Mexican endemic cacti species.

The objective of the study was to evaluate the antimicrobial activity of aqueous and ethanolic Moringa oleifera leaf, stem and seed extracts against multidrug-resistant Staphylococcus aureus strains isolated from raw milk in Hidalgo Mexico in 2017. The conventional method was used to identify and isolate S. aureus. All isolates were screened for antibiotic sensitivity to 12 antibiotics using the diskdiffusion method, in order to select twenty multidrug-resistant strains. The antimicrobial activity of the M. oleifera leaf, stem and seed extracts (aqueous and ethanolic) was tested using the disk-diffusion agar method, with penicillin used as a positive control. Sixty-five S. aureus strains were isolated from 56% of the raw milk sample, with an average count of 4.5 x 10 5 CFU/ml, this is considered as a potential public health risk. All the S. aureus strains exhibited resistance to at least two antibiotics. Sixty-five strains exhibited resistance to penicillin and ampicillin. In contrast, all showed sensitivity to ciprofloxacin. Ethanol extract exhibited a higher degree of antimicrobial activity compared to the aqueous extracts and penicillin. This reveals that the leaves, stems and seeds of M. oleifera could be an alternative for the control of infections caused by S. aureus in humans and cows with mastitis.

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