This work evaluates the experimental warming effects on phenology and grain yield components of wheat in the Yaqui Valley, Sonora, México, using CIRNO C2008 variety fromTriticum durumL., as a model during the cropping cycle of 2016–2017 (December to April). Infrared radiators were deployed to induce experimental warming by 2 °C above ambient crop canopy temperature, in a temperature free-air controlled enhancement system. Temperature was controlled by infrared temperature sensors placed in eight plots which covered a circle ofr= 1.5 m starting five days after germination until harvest. The warming treatment caused a reduction of phenophases occurrence starting at the stem extension phenophase. Such phenological responses generated a significant biological cycle reduction of 14 days. Despite this delay, CIRNO C2008 completed its biological cycle adequately. However, plant height under the warming treatment was reduced significantly and differences were particularly observed at the final phenophases of the vegetative cycle. Plant height correlated negatively with spikes length, spikes mass, and number of filled grains. Warming also reduced grain yield in 33%. The warming treatment caused a stress intensity (SI = 1-yield warming/yield control) of 39.4% and 33.2% in biomass and grain yield, respectively. The differences in stress intensities between biomass and grain yield were based on plant height reduction. Grain mass was not affected, demonstrating the crop capability for remobilization and adequate distribution of elaborated substances for the spikes under warming conditions.

This study was carried out during January 2020–December 2020 in a semi-desert ecosystem in southern Sonora, Mexico, to determine the annual and daily variations in water potential and the normalized difference vegetation index (NDVI) of Bursera fagaroides Engl., Monogr. Phan., Parkinsonia aculeata L., Sp. Pl.; Prosopis laevigata (Humb. & Bonpl. ex Willd.), and Atriplex canescens (Pursh) Nutt. Soil electrical conductivity, cation content, and physical characteristics were determined at two depths, and water potential (ψ) was measured in roots, stems, and leaves. The daily leaf ψ was measured every 15 days each month to determine the duration of stress (hours) and the stress intensity (SI). The electrical conductivity determinations classified the soil in the experimental area as strongly saline. A significant difference was noted in electrical conductivity between soil depths. The four studied species showed significant gradients of ψ in their organs. In this soil, all four species remained in a stressed condition for approximately 11 h per day. The mean SI was 27%, and B. fagaroides Engl., Monogr. Phan. showed the lowest value. The four species showed increased NDVI values during the rainy months, with P. laevigata (Humb. & Bonpl. ex Willd.) and Parkinsonia aculeata L., Sp. Pl. showing the highest values. The capacity for ψ decrease under saline conditions identified A. canescens (Pursh) Nutt., B. fagaroides Engl., Monogr. Phan. and P. aculeata L., Sp. Pl. as practical and feasible alternatives for establishment in saline soils in southern Sonora for purposes of soil recovery and reforestation.

Under soil saline conditions, biochemical alterations occur during plant-arbuscular mycorrhizal fungi (AMF) interactions, depending on the fungal strain involved and the intensity of the stress. This study aimed to evaluate the infectivity and efficacy of Rhizophagus irregularis by analyzing the biochemical responses it induces in chickpea (Cicer arietinum L.) cv. ʽNacional-29ʼ under 50 mM NaCl stress. Nacional-29 is a chickpea variety developed at the Institute of Fundamental Research in Tropical Agriculture (INIFAT) “Alejandro de Humboldt” and is classified as susceptible to salinity when the soil saturation extract exceeds 30 mM. The effect of an AMF strain (INCAM 11 of Rhizophagus irregularis) from the INCA collection was assessed in chickpea plants regarding root colonization, accumulation of cytocompatible osmolytes, and the activity of various antioxidant enzymes. The analysis demonstrated enhanced antioxidant defense mechanisms, a significant increase in proline accumulation in the leaves of stressed mycorrhizal plants, and a substantial reduction in lipid peroxidation, with levels even lower than those in the inoculated control plants. The applied salt stress caused a redox imbalance, leading to a reduction of POX, SOD, and APX by 35%, 20%, and 25%, respectively, while increasing free radical levels. However, the inoculated stressed plants exhibited higher levels of total soluble carbohydrates and increased catalase and glutathione reductase activity, indicating that redox homeostasis was crucial for salinity tolerance. These findings indicate that R. irregularis enhances antioxidant defense mechanisms in chickpea plants, thereby improving their salinity tolerance. This could have significant implications for agricultural practices, particularly in developing strategies to enhance crop resilience in saline soils. Arbuscular mycorrhizal fungi, such as R. irregularis, provide a sustainable solution for enhancing crop productivity in saline-affected areas, thereby contributing to food security in regions facing soil salinity challenges.

Peppers need to be characterized for the in situ conservation of species that might be important for breeding purposes. In this study, we characterized the diversity of 23 pepper genotypes through eight qualitative and 12 quantitative descriptors. The pepper samples were collected from the city of Manaus and in the municipalities of Rio Preto da Eva and Iranduba in the state of Amazonas. We performed descriptive analysis, analysis of variance, Pearson’s correlation analysis, and principal component analysis (PCA) and used the unweighted pair group method with arithmetic mean (UPGMA) to analyze the data. The differences between the genotypes for all descriptors evaluated were significant. Among the genotypes collected, four pepper species were identified, including Capsicum chinense (14 genotypes), Capsicum frutescens (two genotypes), Capsicum baccatum (one genotype), and Capsicum annuum (four genotypes), and two other genotypes were obtained with unidentified species. The PCA and UPGMA clustering methods could be used to efficiently differentiate between the genotypes by applying quantitative and qualitative descriptors of fruits and seeds. These methods helped to identify different genotypes (G1 and G15) and separate them into distinct groups associated with the distribution of species based on quantitative data only. Overall, our findings suggested that the genetic variability in Capsicum available in the State of Amazonas might be useful in breeding programs.