“… an important issue is the diversification of nutrient sources, necessary to generate a productive system of greater harmony with the environment…”
Juan Hirzel Campos is a researcher and agricultural extensionist at the Chilean Agricultural Research Institute – INIA, specializing in soil fertility and plant nutrition.
Hirzel is an agronomist at the University of Talca, has a master’s degree from the University of Concepción and a doctorate from the Polytechnic University of Madrid.
AgriBrasilis – What is INIA’s role in agricultural research in Chile?
Juan Hirzel – INIA is a leader in applied research in agricultural production in Chile and generates guidelines and management strategies to be followed for most crop species cultivated in the country, as well as for livestock production.
AgriBrasilis – How is fertilizer management carried out for the main agricultural crops in the country?
Juan Hirzel – Fertilization management in Chile is carried out mainly using chemical fertilizers and, to a lesser extent, using organic compost fertilizers*.
The application doses are determined by fertilizer companies or technical advisors from different agricultural areas, guided by fertilization guidelines created by INIA, national universities, or foreign research centers focused on agricultural products for export.
Fertilization can be carried out by traditional methods for conventional agriculture, or through fertigation.
In times of normal fertilizer values, fertilization is between 8% and 40% of the direct costs of the country’s agricultural inputs, but in the last agricultural season those direct costs showed an increase.
The products with greatest demand are conventional fertilizers, but in the last harvest the demand for organic compost fertilizers increased strongly. In third place there is a demand for foliar fertilizers or foliar nutritional supplements.
AgriBrasilis – How did Chile deal with the fertilizer supply crisis? What alternative technologies have been adopted to mitigate this crisis?
Juan Hirzel – The fertilizer supply crisis has been faced with the knowledge generated about soil fertility and about the response of crops to nutrient application, that has allowed the adjustment of the doses of nutrients applied, and through knowledge of the use of organic fertilizers as a nutrient source.
An important issue is the diversification of nutrient sources, necessary to generate a production system of greater harmony with the environment, in terms of carbon nutrition for biomass and soil trophic chains, construction of physical, chemical, and biological fertility and control of mineral nutrient deliveries to cultivated plants, reducing risks of nutrient losses, like what happens with nitrogen. Losses are very common with the use of conventional fertilizers.
The diversification of nutritional sources generates a better management of the consumption and use of nutrients by the soil-plant system, contributing to the care of the environment and the reduction of direct production costs.
INIA is a national and regional leader in the generation and dissemination of knowledge about fertilizers and organic fertilizers, with more than 22 years of experience in research on this subject. Emphasis on the fertilization of crops and fruit trees, in which the use of organic compost fertilizers has been presented as an alternative, with dosage and application guidelines.
*Organic compost fertilization:
There are different types of organic compost fertilizers available in Chile, that are by-products or residues of different productive activities. In general terms, they can be classified as:
- Organic by-products of animal origin: guanos (bird and bat feces), manure and slurry.
- Liquid industrial waste treatment. Among them are sewage sludge, industrial sludge, waste production processes, fish farming residues, etc.
- Industry by-products or from other productive activities. Waste from the sugar industry, animal slaughterhouses and others.
In general, the nutrient content of organic fertilizers is low. However, due to the large volumes generated, they become an important resource of nutrients for the soil. This nutrient content is divided into an organic fraction and a soluble (or available) fraction, the latter being the most quickly available for absorption by plants.
Adapted from “Uso de enmiendas orgánicas como fuente de fertilización en cultivos” (Hirzel; Sperberg)