Climate change has challenged large-scale crop production at a global level. Global temperature increases, water scarcity, and a further reduction in cultivable land resources due to anthropogenic impacts have resulted in the need to redesign agricultural systems such as intercropping to maximize the efficient use of natural resources. Arbuscular mycorrhizal fungi (AMF) represent an underexplored area, not only in terms of an alternative to the heavy use of chemical fertilizers, but also as a natural resource used to enhance physiological processes and mitigate the variations in biotic and abiotic factors in plants. On the other hand, the combined use of AMF with suitable but cheaper and environmentally friendly growth substrates is another way to maximize crop production. A study was carried out in a tomato and onion intercropped pattern system to analyze the above- and belowground implications of two AMF commercial products containing Rhizophagus irregularis, propagated in soil and with an in vitro technique addition, with two different mixed growth substrates (river sand and compost) under greenhouse conditions. Overall, both AMF products overall showed significant promoting effects on plant growth (15–30%) and root parameters (50%) in the tomato and onion plants on the sand-mixed substrate. Moreover, the soil-propagated AMF also showed significant positive effects on chlorophyll content (35%), photosynthetic activity, and the accumulation of macro- and micronutrients, especially the Fe and Mn contents (60–80%) in the tomato plants. We present evidence of the benefits to plant performance due to the interactive effects between AMF and the growth substrate, and these positive effects might be due to the intercropping system. Hence, soil-propagated Rhizophagus irregularis is represented here as a promising candidate for enhancing growth, sustainability, and productivity under greenhouse conditions.

Satureja macrostema is a plant that is located in various regions of Mexico and is used in a traditional way against illness. Essential oils (EOs) were obtained from leaves Satureja macrostema and the chemical composition was evaluated by gas chromatography–mass spectrometry (GC-MS). The antioxidant effect of the oil was assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and by Trolox Equivalent Antioxidant Capacity (TEAC). In vitro antibacterial activity against Escherichia coli and Staphylococcus aureus was determined using a broth microdilution assay and thin layer chromatography–direct bioautography (TLC-DB) to identify active antibacterial compounds. The EOs analysis showed 21 compounds, 99% terpenes, and 96% oxygenated monoterpenes, with trans-piperitone epoxide (46%), cis-piperitone epoxide (22%), and piperitenone oxide (11%) as more abundant compounds. Likewise, S. macrostema EOs showed an antioxidant activity of DPPH = 82%, with 50% free radical scavenging (IC₅₀) = 7 mg/mL and TEAC = 0.005, an antibacterial effect against E. coli of 73% inhibition, and 81% over S. aureus at dose of 100 µL of undiluted crude oil. The TLC-DB assay showed that the most active compounds were derived from piperitone. The comparison with other studies on S. macrostema shows variability in the compounds and their abundances, which can be attributed to climatic factors and the maturity of plants with similar antioxidant and antibacterial activities.

El estudio de respiración del suelo (emisión microbiana de CO2) por incorporación de residuos orgánicos (RO) provenientes de la agroindustria (bagazo y composta de bagazo), permite estimar el efecto ambiental en relación a la emisión de CO2 por la mineralización del carbono durante su proceso de descomposición, lo cual debe ser considerado desde el punto de vista de cambio climático. Por lo anterior, el objetivo fue evaluar la dinámica de emisión de CO2 por la mineralización de cuatro materiales lignocelulósicos, incorporados en suelos de diferente textura. Mediante la técnica de respiración alcalina, se cuantificó la respiración de CO2 en Regosol y Luvisol por incorporación de dos bagazos (TBD y TBA) y sus compostas (TCD y TCA) durante 30 días bajo condiciones controladas de humedad y temperatura. Los tratamientos TBD y TBA, incrementaron la actividad microbiológica con mayores emisiones; mientras que los tratamientos TCD y TCA, incrementaron el contenido de C orgánico suelo (COS) con menores emisiones. La emisión de CO2 se relacionó con la mineralización de los RO y ésta a su vez con su composición química y su resistencia a la descomposición, además la dinámica de las emisiones fue diferente por tipo de material y por tipo de suelo. La incorporación de RO de tipo bagazos, es una opción para incrementar la actividad microbiana edáfica, pero con mayor emisiones de gases de efecto invernadero (GEI); mientras que los RO de compostas generan un incremento en la captura de COS y, por ende, mayor almacén de C y una menor emisión de CO2.