The use of amendments in combination with Bacillus subtilis has been understudied as a strategy for rehabilitating acid soils and improving cropping systems. This study aimed to evaluate the effects of amendments and B. subtilis on the development, yield, and nutritional quality of the hard yellow maize Marginal 28 T variety. A randomized complete block design with a factorial arrangement was employed, considering five amendments, including biochar, alongside the application of B. subtilis. The combination of biochar and B. subtilis significantly increased plant and ear height (p < 0.01), achieved a grain yield of 4.11 t ha⁻¹, and reduced flowering time by seven days. Strong correlations were observed between male and female flowering (r = 0.99) and between stem diameter and leaf area (r = 0.95), indicating improved vegetative development. Soil pH and nutrient availability, such as phosphorus, were also enhanced. The combined use of amendments and B. subtilis optimizes yield and improves soil chemical properties. Thus, applying biochar and B. subtilis improves growth, yield, and soil quality, consolidating a promising strategy for sustainable agriculture in acid soils.

The study was conducted in Juan Guerra district, province and region of San Martin, Peru; it assessed two treatment sets: (1) nitrogen fertilizer dose (FN75, FN100); (2) green manure Crotalaria juncea (CroJ), Canavalia ensiformis (CanE), and without green manure. It was arranged in a split-plot design with four replications. During the experiment, we observed an important fluctuation in soil parameters. Notably, there was a decrease in soil carbon and nitrogen levels, likely attributed to microorganism metabolism. On the other hand, we observed that CanE significantly reduced the diseased tillers through “White Leaf Virus” (RHBV) by 2.82% compared to the control, and significant panicle fertility was achieved by CroJ (91.88%). No significant differences were obtained in yields during this first campaign; however, the highest reported yield was 8.36 t ha-1 with the CanE - FN100 treatment. Additionally, the nutritional quality of the rice was not affected by either green manuring or the application of chemical nitrogen fertilization. These findings allow deeper studies to consider strategic alternatives to reducing dependency on inorganic fertilizers among the poorest communities. Highlights: A reduced incidence of White Leaf Virus (RHBV) was observed with the use of green manures. Rice variety INIA 507 "La Conquista'' reached 8.36 t ha-1 under tropical climate conditions. Canavalia ensiformis accompanied by nitrogen fertilization produced the highest yield. Replacing 25% of chemical nitrogen fertilization with Canavalia or Crotalaria green manures did not significantly affect rice yield. Replacing chemical nitrogen fertilization with green manure did not affect the nutritional quality of rice.

Background. The morphological quality of cocoa (Theobroma cacao L.) seedlings in the nursery is essential for the success of commercial plantations. Bioferments represent a sustainable alternative to improve the morphology and quality of seedlings. Objective. To evaluate the effect of bioferments on the morphology and quality of cocoa seedlings in the nursery. Methodology. Four treatments were used with different combinations of substrates and solid and liquid bioferments. A completely randomized design with four repetitions was used, measuring morphological and quality variables. Results. The traditional substrate treatment with the addition of solid and liquid bioferments (ST+BS+BL) showed the highest values in height, stem diameter, dry biomass and Dickson quality, surpassing the traditional substrate by 51%. Implications. Bioferments improve the availability of nutrients and the structure of the substrate, favoring the development of vigorous and better quality seedlings. Conclusions. The combination of solid and liquid bioferments represents an agroecological strategy to optimize the morphological attributes and quality of cocoa seedlings in the nursery.

Soil heterogeneity and acidity are major constraints to Coffea arabica production in the Amazonian soils of Peru. This study developed a spatial predictive framework that integrates a weighted Soil Quality Index (SQIw) and geostatistical modelling (Regression–Kriging and Ordinary Kriging) to estimate lime requirements (LRs) and delineate management zones. A total of 69 coffee-cultivated soil samples were analysed, and spectral information (NDVI) was incorporated to estimate relative yield (RR). Multivariate analysis defined a Minimum Data Set (MDS) composed of exchangeable Na, available P, pH and silt percentage; the highest weights were assigned to P (Wi = 0.292) and pH (Wi = 0.276). SQIw exhibited wide variability (0.01–0.87; CV = 51.8%) and was grouped into five classes, with low (43.5%)- and very low (21.7%)-quality classes predominating. SQIw showed a strong relationship with RR (r = 0.64). Geostatistical models performed differently between localities: in Nuevo Huancabamba, Regression–Kriging improved prediction accuracy (SQIw: R² = 0.58; LR: R² = 0.396), whereas in San José de Sisa, Ordinary Kriging provided better fits only for LRs (R² = 0.32). Nuevo Huancabamba is dominated by moderate-to-high-quality soils (87.29%; SQIw > 0.6) and low lime requirements (74.94%; <0.84 t ha⁻¹), in contrast with San José de Sisa, where low-quality soils prevail (89.45%; SQIw < 0.4) alongside high LRs (75.26%; 2.54–7.13 t ha⁻¹). The resulting maps enable targeted interventions—precision liming and focused P fertilisation—to correct acidity and phosphorus deficiency, thereby improving input-use efficiency and enhancing the sustainability of Amazonian coffee systems.

Background: The utilization of organic fertilizers is put forward as an effective approach to address soil degradation and enhance crop yields. Objective: To assess the impact of applying microbial consortia, in combination with fermented liquid fertilizer (biol), on maize grain production, with a focus on fostering sustainable family farming in dry tropical conditions. Methodology: A randomized complete block design with three blocks and divided plots was employed, with the main plots featuring various maize cultivars, while the subplots consisted of four bioferments and a control treatment. The bioferments included Microbial Consortium (CM), BIOL+CM, and BIOL+EM-1, compared to the commercial product Efficient Microorganisms (EM-1) and a control with no application. Parameters such as days to male and female flowering, plant and ear height, leaf area, grain diameter, and yield, along with the physical and chemical soil characteristics, were evaluated following the bioferment application. Results: The application of BIOL+CM to the Marginal 28T variety resulted in increased plant height (164.17 cm) and cob size (65.83 cm), as well as a larger leaf area (361.17 cm²). It also enhanced the grain yield of the Marginal 28T variety (3.42 tꞏha-1) and the HS-1 hybrid (3.02 tꞏha-1). Implications: The combined use of locally-sourced microbial consortia and Biol significantly improves the agronomic performance of hard yellow corn and aids in maintaining the soil's physical and chemical conditions, thereby promoting its enhancement. Conclusion: The Marginal 28T variety and the HS-1 hybrid exhibited a favorable response to the application of microbial consortia, particularly BIOL+CM, making it a viable option for family farming in dry tropical conditions.

La obtención de plantas vigorosas de Plukenetia volubilis L. en vivero es fundamental para su establecimiento en campo. El objetivo fue evaluar el efecto de un biofermento comercial y uno artesanal, aplicado solo y complementado con extracto de Azadirachta indica sobre el crecimiento, la distribución de biomasa y la calidad morfoestructural de P. volubilis L. en vivero. Se utilizó un diseño completamente al azar, distribuido en cuatro tratamientos: testigo, biofermento comercial (EM), biofermento artesanal (ML) y biofermento artesanal complementado con extracto de A. indica (ML+N), con cinco repeticiones de 20 plantas. Los tratamientos se aplicaron directamente al sustrato de cada planta a los 15 y 30 días después de la siembra, y las respuestas de las plantas se evaluaron durante 45 días. Se evaluaron variables morfológicas, biomasa seca e índices de calidad. Los datos se analizaron mediante análisis de varianza, prueba de Tukey, correlación de Pearson y análisis multivariados. Los tres biofermentos registraron efectos beneficiosos respecto al testigo, con incrementos de 18-23% en el diámetro de tallo y 40-45% en la longitud radical. Asimismo, la biomasa seca total aumentó de 2,65 g a 3,80–3,91 g y el índice de calidad de Dickson aumentó de 0,11 a 0,21–0,22. ML incrementó el número de raíces y el área foliar y mostró un desempeño comparable a EM, mientras que la adición de A. indica no proporcionó ventajas adicionales. Los biofermentos favorecieron la producción de plantas de P. volubilis más robustas y con una distribución de biomasa más equilibrada en condiciones de vivero.