Currently, in much of the country the cultivation of corn is in full development at different stages. We spoke with Ing. Agr. Jorge Simko, on what works the producer must carry out in relation to fertilization, weed control, pests and diseases.
“So far the development of corn is well under way, but we all know that the producer depends on the good behavior of the climate to achieve the success of his cultivation; however, there is the commitment of the one who sows and who must also do his part. With regard to sowing, the corn that has a more complicated scenario is the one that was sown between the second half of February until the first half of March and even later, considering that if we are talking about a super-early 125 to 130 days , it would be reaching its grain-loading stage at a time of high risk of frost (July) ”, the engineer from the Agrotec firm began by explaining.
Fertilization and extraction
“To understand the importance of good fertilization, we will focus on nitrogen (N), we have the nutrient extraction table by crop; Therefore, to achieve a production of 7,000 kilos of corn grain per hectare, 166 points of nitrogen are needed, which is what the plant extracts from the soil, the harvest index is 63 percent, therefore in the grains the plant takes 105 nitrogen points, and the rest remains in the soil (61 points). With this value, the producer must contribute more than 200 kilos of urea (N) to the soil to reach the 105 nitrogen points that the corn plant needs to load an ear (fundamental will always be the soil analysis) ”.
Time to weed control
When it comes to weed control, engineer Simko said: “We recommend doing weed control early, with exposed plants and before the rows are closed. Post-emergent herbicides (glyphosate or glufosinate ammonium depending on the technology that the corn has) and pre-emergent herbicides (atrazine) are generally used; as a reminder, atrazine can be applied against weeds in corn without technology from 3 true leaves ”.
Speaking of insect control, the professional said: “With the first germination of corn, everything must be monitored for the bed bug complex; Therefore, if you can, you should start drying the soybeans to lower the pressure, and if you have not done so, more applications will be needed; a product with acephate is recommended from the emergency and at most in stage V5 ”.
“Then we continue with the control of cigarillos, monitoring and control until the Vn stage, which would be the vegetative part before flowering. The mere presence of the cigarillo should already imply an application, and always recommend a rotation of insecticides of chemical groups and mode of action (it can be systemic or contact). Let us remember that the cigarillos are sucking insects and also vectors of the mollicutes that are the cause of pale or reddish stunting in corn ”.
“During the period of control of bedbugs and cigarillos, the control of caterpillars must also be taken into account, depending on the biotechnology and the hybrid that the producer has planted, therefore we must emphasize those that do not have biotechnology”, explained our interviewed.
“We should point out the following in terms of disease control. Monitoring must be constant and depending on the susceptibility of the hybrid, one or two systemic fungicide applications should be carried out in a mixture with a protective fungicide (example mancozeb); the first application is recommended in V8, and the second application is recommended in pre-flowering. Another of the main diseases to take into account is the white spot (on leaves), which is a fungus that complicates the plant’s photosynthesis capacity ”, concluded the engineer.