Arbuscular mycorrhizal fungi (AMF) are obligate biotrophs that supply mineral nutrients to the host plant in exchange for carbon derived from photosynthesis. Sucrose is the end-product of photosynthesis and the main compound used by plants to translocate photosynthates to non-photosynthetic tissues. AMF alter carbon distribution in plants by modifying the expression and activity of key enzymes of sucrose biosynthesis, transport, and/or catabolism. Since sucrose is essential for the maintenance of all metabolic and physiological processes, the modifications addressed by AMF can significantly affect plant development and stress responses. AMF also modulate plant lipid biosynthesis to acquire storage reserves, generate biomass, and fulfill its life cycle. In this review we address the most relevant aspects of the influence of AMF on sucrose and lipid metabolism in plants, including its effects on sucrose biosynthesis both in photosynthetic and heterotrophic tissues, and the influence of sucrose on lipid biosynthesis in the context of the symbiosis. We present a hypothetical model of carbon partitioning between plants and AMF in which the coordinated action of sucrose biosynthesis, transport, and catabolism plays a role in the generation of hexose gradients to supply carbon to AMF, and to control the amount of carbon assigned to the fungus.

Ensuring food security through sustainable systems remains a key goal for the agricultural sector. However, poor crop management practices in recent decades have caused significant ecological harm, evidenced by climate change impacts, soil degradation, and water scarcity. Biotic and abiotic stresses during crop development further reduce yield and quality. Reviving traditional farming practices, such as the milpa system, offers a solution to boost production sustainably while repairing past damage. This comprehensive polyculture system centers on maize, intercropped with beans, squash, chili, fava beans, and other crops. Ecologically, milpas enhance biodiversity, improve soil physicochemical properties, and mitigate environmental harm through beneficial interactions among plants, insects, and microorganisms. This work examines these interactions, with a focus on the role of beneficial microorganisms in reversing environmental damage and revitalizing milpa systems. Adopting these tools can strengthen traditional practices, promoting sustainability and ensuring food security.

Swietenia macrophylla is a tropical timber species of ecological and economic importance. However, its slow vegetative growth and root development in nurseries strongly limit its production. This study evaluated the effect of 10 rhizobacteria strains during the early stages of production of S. macrophylla. Superficially disinfected seeds were inoculated with rhizobacteria under commercial nursery conditions. Inoculation was complemented by initial fertilization without growth regulators, fungicides, or bactericides. The results indicate that the rhizobacteria strains induce different responses in plants. Significant differences in plant biomass and root architecture were found. Treatments inoculated with Bacillus sp., Bacillus polyfermenticus, and Bacillus siamensis strains; showed an increase of up to 41% (dry weight). Plants increased root biomass by 30% when inoculated with S. siamensis. All inoculated strains were identified as members of the genus Bacillus spp., and their presence three months after inoculation was assessed by 16S rRNA gene-based amplicon massive sequencing. We found that Bacillus sp. genus was only present in inoculated treatments, suggesting that inoculated bacteria could establish themselves successfully as part of the microbiota. These results support the advantages of using PGPRs in commercial tropical tree production.

Una de las estrategias agroecológicas que aumenta la producción agrícola es el uso de inoculantes bacterianos, los cuales carecen de los efectos tóxicos que tienen los agroquímicos. En este trabajo se evaluó el efecto de la inoculación de la rizobacteria promotora del crecimiento vegetal Pseudomonas fluorescens UM270 sobre el ciclo de cultivo de plantas de tomate de cáscara (Physalis ixocarpa) en condiciones de campo (riego) en el año 2019. Los resultados mostraron que las plantas inoculadas con la rizobacteria UM270 exhibieron efectos significativos en la altura de las plantas (14.64%), el diámetro de tallo (17.74%), el índice de biovolúmen (35.14%) y la producción de frutos cuajados en 65.54%. Esto sugiere que la cepa P. fluorescens UM270 es un excelente bioinoculante que mejora la producción del cultivo de tomate de cáscara bajo condiciones de campo.