Tropical grassland soils, especially those with alkaline properties, often exhibit limited phosphorus availability due to its precipitation in insoluble forms. Phosphate-solubilizing bacteria (PSB) and rhizobia have demonstrated their potential to enhance the availability of this nutrient and promote the growth of forage legumes. This study, conducted under controlled conditions in a mesh house, evaluated the effect of co-inoculation with PSB, including Micrococcus sp. Sfcm-14-01, Agrobacterium sp. Sfl-043-09, and Enterobacter sp. Sfcm-014-02 and Sfcm-054-06, along with rhizobia (Ensifer terangae R1-012-02 and Bradyrhizobium glycinis Rcm-025-01), under different levels of phosphorus fertilization on the legumes Leucaena leucocephala and Centrosema macrocarpum. The results indicate significant increases in various growth parameters, such as chlorophyll levels (SPAD), biomass (dry weight of roots and aerial parts) (mg), the foliar phosphorus concentration (ppm), and the concentration of available phosphorus in the soil, particularly under low-phosphorus fertilization conditions. The highest level of available phosphorus in the soil was achieved with 75% of the recommended fertilization dose, resulting in concentrations of 13.73 ppm for L. leucocephala and 7.69 ppm for C. macrocarpum, representing increases in phosphorus availability of 170.81% and 240.27%, respectively, compared with no fertilization or inoculation. These findings suggest that the co-inoculation of PSB and native rhizobia is a promising strategy to enhance the biomass productivity and mineral content of forage in tropical grazing systems, especially under phosphorus-limited conditions.

El adecuado desarrollo ganadero debe haber un punto de equilibrio entre la producción animal y los servicios ambientales. El objetivo del estudio fue realizar evaluaciones agronómicas en cuatro sistemas silvopastoriles (SSP). Para ello, se instalaron 16 ha de pasturas (sistema de pastura sola con Brachiaria brizanta; sistema de manejo con sucesión vegetal; sistema de pastura con leguminosas arbustivas; y sistemas como bancos de energía y proteínas) en un ecosistema de bosque seco tropical en la región San Martín, Perú, en un periodo de cinco meses. El resultado de las evaluaciones agronómicas, demostraron que el comportamiento de las especies forrajeras introducidas, tanto gramíneas utilizadas como pasto de cobertura y de corte, así como leguminosas arbustivas utilizadas como cercos vivos; la evaluación nutricional en cuanto a materia seca (MS), fibra detergente neutra (FDN) y proteína total, efectuado a 120 días de la siembra no se encontraron diferencias significativas (p<0,05), en los SSP con cobertura de Brachiaria brizantha, demostrando que a esa edad de las pasturas todavía no se observan efectos de los cuatro diferentes sistemas evaluados; en las especies forrajeras introducidas en los SSP, se encontró una gran variabilidad en los índices nutricionales evaluados.

Common bean ( Phaseolus vulgaris L.) is a globally important legume with significant nutritional and agronomic value. Genetic diversity in Amazonian landraces remains undercharacterized, limiting their utilization in breeding programs. Here we analyzed 647 accessions from the Peruvian Amazon using 18 morphological traits and 23,050 high-quality DArTseq single nucleotide polymorphisms (SNPs). Our results revealed two major genetic groups corresponding to Andean and Mesoamerican gene pools, each subdivided into distinct subgroups, exhibiting high allelic richness and structured diversity. Despite abundant polymorphic loci, observed heterozygosity was low, consistent with the species’ self-pollinating nature. These findings highlight the Peruvian Amazon as a reservoir of unique genetic variation, underscoring the need for integrated in situ and ex situ conservation strategies. This germplasm offers valuable resources for breeding programs targeting tropical adaptation and resilience, contributing to sustainable agriculture and food security.

Iron deficiency remains a major public health challenge in populations relying on staple foods with low iron bioavailability, including polished rice. This narrative review evaluates how beneficial plant-associated microorganisms may support iron (Fe) biofortification by influencing Fe mobilization in the rhizosphere, root acquisition, and subsequent transport to edible tissues. We organize the existing evidence along a soil–plant–grain–food continuum and distinguish measured outcomes from proposed mechanistic links. This evidence-based framework is described as a plant–microbe biomanufacturing platform in a strictly conceptual sense: neither plants nor microorganisms manufacture Fe; rather, their interactions can modify its mobilization and distribution. Most studies have demonstrated microbial effects on Fe availability and plant physiology, but fewer have established increased Fe in grain, and evidence for Fe being retained after polishing or absorbed by consumers remains scarce. Future work should integrate field validation, nitrogen and water management, Fe localization, food processing, and nutritional bioavailability. This approach may help prioritize testable interventions without equating microbial activity or higher total grain Fe with improved human iron status.

Legumes (Fabaceae) are key functional components of tropical forests due to their role in nitrogen fixation and nutrient cycling. This study provides an integrated assessment of forest legume diversity and its relationship with soil physicochemical properties across three protected areas in the Peruvian upper Amazon: the Alto Mayo Protected Forest (BPAM), the Cordillera Escalera Regional Conservation Area (ACR-CE), and the Shunté and Mishollo Forests Regional Conservation Area (ACR-BOSHUMI). Floristic studies were conducted in nine sectors ranging from 618 to 1729 m a.s.l. Soil samples were analyzed, and vegetation cover was quantified using high-resolution drone imagery with four vegetation indices derived from RGB data. We recorded eleven legume species from eight genera within the sampling plots, identifying Inga as the most frequent genus. Species diversity was highest in the ACR-CE, whereas BPAM showed lower richness and abundance. Multivariate analyses revealed that legume diversity was positively associated with higher soil pH, cation concentrations, and cation exchange capacity, but negatively associated with elevated Al³⁺ and Fe³⁺ levels. Vegetation indices effectively distinguished between vegetated and degraded areas, indicating higher legume occurrence in sites with greater canopy cover. These findings emphasize that soil fertility and vegetation structure are key drivers of legume diversity, with significant implications for conservation in the upper Amazon.

Common bean ( Phaseolus vulgaris L.) is a globally important grain legume, yet the genetic diversity of landraces from the Peruvian Amazon remains poorly characterized. This study aimed to assess the population structure and genetic diversity of Amazonian common bean by integrating morphological and genome-wide SNP data. A total of 476 accessions were phenotyped using 18 morphological traits, and 647 accessions were genotyped with 23,050 high-quality DArTseq SNP markers. Cluster and population structure analyses consistently identified two major genetic groups corresponding to the Andean (n = 284) and Mesoamerican (n = 363) gene pools, with further subdivision into four subgroups at K = 4. Principal Coordinate Analysis supported this structure, with the first axis explaining 62.62% of the variation in the molecular data. Genetic diversity was high, with 94.9% of SNPs successfully mapped and more than 94% of loci polymorphic in both groups. However, observed heterozygosity was low (Ho = 0.035–0.041) compared to expected heterozygosity (He ≈ 0.147–0.148), and inbreeding coefficients were high (FIS = 0.52–0.54), consistent with the predominantly self-pollinating mating system. Hill number analyses indicated similar allelic richness between groups (q = 0: α ≈ 1.95–1.97) and low differentiation in allele presence (β = 1.04), whereas differentiation increased when allele frequencies were considered (q = 2: β ≈ 1.4–1.5). Morphological analyses revealed substantial phenotypic variation, including flowering time (32–75 days), pod length (6.5–17.3 cm), and number of locules per pod (2–11), and identified four distinct phenotypic clusters. No redundant accessions were detected. These results indicate that Amazonian landraces harbor high levels of genetic and phenotypic diversity structured by gene pool origin and local adaptation. The integration of morphological and SNP data provides a robust framework for germplasm characterization and highlights the importance of conserving these genetic resources for future breeding and sustainable agriculture.