Fertilization Keys to Mitigate Cadmium in Cocoa

• A fertilization plan based on integrating mineral, organic, and microbial approaches successfully reduced cadmium levels in cocoa, according to the results of three years of research conducted on farms in Arauca. The study, led by AGROSAVIA, identified practices that limit the absorption of this metal by plants, improve productivity, and contribute to safer and more sustainable cocoa cultivation.

 

Mosquera, Cundinamarca. April 30, 2026. Under the leadership of Daniel Bravo, Ph.D., Associate Researcher at AGROSAVIA’s Tibaitatá Research Center, a study was carried out to identify the most effective treatments within a fertilization plan focused on mitigating cadmium (Cd) in cocoa crops. As a result, two recent scientific publications present the findings of three years of applied research conducted on 20 pilot farms located in the leading cocoa-producing municipalities of Arauca: Arauquita, Fortul, Saravena, and Tame.

 

Most Relevant Results

The research was conducted under two complementary approaches. The first, published on April 7, 2026, evaluated nine treatments combining different proportions of three components: a chemically synthesized fertilizer (Agrocacao), a Colombian-origin zeolite (zeocol), and a bioproduct currently under development at AGROSAVIA, based on Cd-tolerant bacteria previously isolated by the bioremediation team led by Bravo.

The treatments were applied and monitored over a two-year period, with the participation of researchers from the El Nus, Tibaitatá, and La Libertad Research Centers. This work enabled the identification of treatments with statistically superior responses compared to the controls, from which a fertilization recommendation plan based on bioremediation principles was developed.

According to Santiago López, co-author of the article: “This combined strategy significantly contributes to reducing Cd absorption and translocation in cacao trees, strengthening crop nutrition and improving yields. In addition, it promotes the production of safe and sustainable cocoa, with direct benefits for soil health, food safety, and the income of cocoa-growing families.” Meanwhile, researcher Yajaira Romero highlighted her experience in data analysis and the consolidation of scientific results, describing it as “enriching and innovative.”

The study, entitled Fertilization Based on a Chemical, Mineral, and Microbiological Approach to Mitigate Cd Content in Cacao Crops in Arauca, Colombia, was published in the journal Discover Environment (Springer) and is available through open access (article link: https://link.springer.com/article/10.1007/s44274-026-00677-5).

The second study, recently published in the journal 3 Biotech (also published by Springer), focused on validating the bioremediation approach under field conditions using advanced tools. In four of the 20 evaluated farms, digital PCR (ddPCR) and isothermal microcalorimetry (IMC) techniques were combined to analyze the presence of the cadA gene, associated with Cd immobilization, and soil microbial activity following the application of the bioproduct. Here is the link to the second open-access article: https://link.springer.com/article/10.1007/s13205-026-04790-3.

The results showed that at higher soil cadmium concentrations, the bioproduct containing tolerant bacteria increases its capacity to immobilize cadmium, contributing to its retention in the soil and reducing its availability to the plant. This work was carried out within the framework of the master’s degree research studies of Laura Álvarez (Universidad Nacional de Colombia, Palmira campus), supervised by Bravo as principal thesis advisor and co-authored with Professor Pedro Brito Brandão from Universidad Nacional de Colombia, Bogotá campus, as co-advisor.

 

Projection and Impact

“These results mark the beginning of a new way of designing fertilization plans by incorporating food safety and harmlessness components into traditional cacao cultivation schemes,” stated Bravo. The team expects to secure new funding sources to scale up and validate these advances, thereby strengthening the development of Nature-based Solutions (NbS) to address critical issues such as the presence of Cd in cocoa production systems. Both studies were part of the project funded by the General Royalties System: Implementation of Agroforestry Strategies and Integration of Advances in Agronomic and Postharvest Management of New Clones to Improve Cocoa Productivity and Quality in the Department of Arauca.