Reducing the application of chlorine by 25% in potassium fertilizations would provide greater productivity and quality in coffee beans, in addition to representing savings in production costs and reducing the contaminating impact of nitrogen in fertilizers.
This was established by the agronomist Jorge Luis Arteta, Master in Agricultural Sciences from the National University of Colombia (UNAL) Palmira Headquarters, who explains that, particularly in Colombia, the best way that farmers find to correct the acidity of the soil and supply the Nitrogen, phosphorus and potassium requirements, among other elements in their crops, is with mineral fertilizers, above chemicals such as ammonia (composed of ammonia NH3) or urea (ammonium with carbon dioxide).
In the case of coffee production, growers use potassium chloride fertilizers as it is the cheapest on the market, despite the fact that it contains 45% chlorine.
In the study, carried out at the Lusitania farm in the El Mesón village, in the municipality of Garzón (Huila) with the support of the company Yara Colombia, the master evaluated for three years the effect of applying said doses of chlorine in aspects such as absorption of nutrients from the grain after flowering until harvest, the productivity and physical and sensorial quality of the cup and the biochemical composition of the green beans before being roasted.
The researcher explains that the key role of potassium as a fertilizer is related to the metabolism of plants, as it helps to improve photosynthesis, the function of enzymes and the transport of sugar, proteins and starch.
“From there, the arabic coffee plants underwent five chloride reduction treatments through applications with four repetitions, like this: the first at 100%, the second at 75% chlorides, the third at 50%, the fourth with 25 % of chloride and one without applications ”.
The plants developed their entire growth, flowering and harvest process; When the fruits were in optimal conditions for harvesting, some were chosen as they grew to see how they absorbed the elements according to the treatments. “We first harvested at 30 days, then at 60, then at 90, and so on until the fruit was ripe, which is between 240 and 280 days,” explains the master.
After two years, the researcher found that by reducing the 25% contribution of chlorides in the fertilization programs, a higher consumption of potassium, nitrogen, calcium and magnesium – important nutrients in the grain – was obtained, in addition to a better productive response . Specifically, it applied 189 kg of potassium, 22 kg of sulfur and 129 kg of chloride, to reduce its use by 25%.
“Coffee uses chloride as a micronutrient, and even when this element is not applied in fertilizers, the plant still needed to absorb it and concentrate it in its fruits,” says thesis.
It also points out that by reducing this amount of chloride, there was a greater efficiency of nitrogen as a macronutrient in coffee. “If the plant takes better advantage of the nitrogen that is applied to it, the coffee grower will have a monetary saving, because if he applies only 100 kg of nitrogen, the coffee plant will be much more efficient and will pollute the atmosphere and the environment much less”.
Lastly, it was verified that arabic coffee continues to be productive, of quality and of mild origin – as Colombian coffee is characterized – by absorbing its nutrients in the different treatments applied.
Coffee production
The master concludes that coffee production must take into account the specific times to apply the elements or nutrients that they contribute to the coffee, that is to say that “it does not always need all the nutrients in the same doses, with the same sources and in a single moment. For example, calcium is required, but largely in the pre-flowering stage and the first 30 days; magnesium is required after 120 days, etc. ”.
According to the National Federation of Coffee Growers, until July of this year Colombia had a production of 1.2 million bags of coffee. Regarding its export, the entity reported a growth of 9% (1.2 million bags of 60 kg of green coffee) compared to the same period of 2020, which means that it recovered a ground lost both by the COVID-pandemic. 19 as per national blockades.
With 148,819 hectares –which contribute 18.07% of the national production–, Huila is the first producer of arabic and standard coffee in Colombia, according to the Federation.
UN News Agency – Unimedios
–
