Fertilize Civil Association presented results of the Network of Nutrition with Potassium, a project that began in 2018 and is also carried out in conjunction with INTA, CONICET, and the Faculties of Agricultural Sciences of the National University Entre Ríos and of Agrarian Sciences of Balcarce .
“The project was designed on the hypothesis of a significant decrease in potassium (K) levels in the country, information that was corroborated with the construction of nutrient availability maps carried out in 2011 and 2018 among pristine soils with soils in production -in a study carried out by the team of Dr. Hernán Sainz Rosas from INTA-FCA Balcarce- in the east of the Pampas region, mainly along the coast of the Uruguay River in Entre Ríos, and also in the east of Santa Fe and northeast of Buenos Aires, which add to the deficiency problem that already existed in soils in the Corrientes province area ”, described Ing. Agr. M. Fernanda González Sanjuan, executive manager of Fertilizar, who, together with Dr. Fernando García, from FCA-UNMdP-Balcarce, coordinate the entity’s Potassium Project.
With this background, Fertilizar AC, INTA, CONICET and the faculties of Balcarce and Entre Ríos began nNew trials in the 2019-2020 campaign in Corrientes and in the east of Entre Ríos in rice, corn, soybean and wheat crops.
“There was a significant response in 50% of the cases of corn, in 40% of soybeans and in 50% of wheat, that is to say that in this percentage of batches low potassium levels were registered and the application of this nutrient resulted in in significant responses, in increase in productivity and, therefore, the profitability of the crop “, said Ing. Agr. Juan Orcellet, from INTA Concepción del Uruguay, in charge of the Entre Ríos rehearsals.
In numbers, lThe maximum mean responses were 301 kg / ha in rice, 1,509 kg / ha in corn, 281 kg / ha in soybeans, and 485 kg / ha in wheat.
With these tests it was possible to make “a preliminary calibration” of the exchangeable potassium analysis with the response of the cultures. “What this calibration shows us is that the yield varies as a function of potassium and we have a 90% relative yield in potassium values in the soil of 250 parts per million (ppm). That is below 250 ppm we would have responses greater than 10% in performance”.
In tests carried out in other regions such as the center-east of Entre Ríos, Santa Fe and Buenos Aires, potassium levels had a lesser decrease and the deficiency is not yet as relevant. “But there are some trends in corn and soybeans already responding to applications that we must watch carefully.”
Likewise, in the response trials in southeastern Córdoba and in central and southeastern Buenos Aires, low potassium levels were not yet present, therefore regions without deficiencies or significant physical responses are considered to date.
In a recent trial started in a field with sandy soils located in the district of May 25, Buenos Aires province, which measured a K level of 240 ppm, potassium chloride applications of 30, 60 and 120 kg / ha and “the visual effect on the development of the crop” was preliminarily verified against the control batch in which potassium was not applied.
“It is good to be able to anticipate what is going to come later, because the potassium deficiency will unfortunately come,” said the INTA 9 de Julio specialist, Eng. Agr. Luis Ventimiglia, who directed this Buenos Aires province essay. “That is why it is good to start generating information: when the problem comes we will know how to act.”
recommendations
By way of summary, Dr. García specified that in the east of Entre Ríos and south of Corrientes, “which would be the axis of Route 14”, there are “clear answers” to fertilization with K, “due to very significant deficiencies ”. He also commented that “the batches have been set by performance and the variable that best explains the difference in environments is the exchangeable K content”.
For this reason, he advised, “do soil analysis to monitor the level of K and fertilize” according to what the result indicates.
García announced that this Network will continue to evaluate the situation along the Paraná coast: in the center-west of Entre Ríos, in the south of Santa Fe and the northwest of Buenos Aires. “For now, in the other areas of the Pampean region, it is simply necessary to continue periodically monitoring the potassium in the soil.”
And he ended with a warning: “it is obvious that to the extent that we continue to extract this nutrient via grain or forage production, and we do not replace it, we will continue to find deficiencies and future response situations.”
Tour of the rehearsals At the end of October, a series of visits to the rehearsals of this Network were organized, with journalists, technicians and producers, specifically to the sites of May 25, prov. Buenos Aires and those of Gualeguaychú and Arroyo Barú, in Entre Ríos, to share progress on the response to potassium in different regions.
“From Fertilizar we promote this type of surveys thinking about the future, highlighting the importance of being proactive to be more successful in the management of nutrients and achieve greater sustainability of the system. We consider it essential to be able to anticipate, understand the dynamics of the nutrient in each region, and anticipate a probable nutrient deficiency ”, concluded Eng. Agr. María Fernanda Gonzalez Sanjuan, executive manager of Fertilizar AC.
