The era of herbicide application technology in soybeans

Agricultural crops are subject to the action of pests, diseases and weeds that can reduce the productivity and quality of harvested materials. In this context, the use of agricultural pesticides represents an important strategy within integrated management.

Crop protection is inherent to agriculture itself. It is necessary to produce food and products for commercial and industrial use, in quantity and quality and at a fair price. None of this, however, would be possible in its entirety without the application of pesticides, especially in the face of increased demands.

However, this process has been questioned by some sectors of society, which makes it necessary to justify its use from different points of view. Most of the objections have their origin in problems or accidents that occurred in the field, resulting from the incorrect use of defensive devices. Therefore, mastering the application technology is essential, in order to ensure that the applied products reach the desired target, without contaminating the environment and the people involved.

Application technology is a science that has evolved a lot in recent years, in order to help farmers in the success of their crops. Reducing spray volumes, selection of adjuvants, tank mixtures and larger areas per machine are challenges that can be overcome with the mastery and implementation of good agricultural practices.

In this scenario, we still expect to grow the use of some products that, if they are incorrectly used, that is, without the implementation of good application practices, could cause losses to farmers, whether they are users or not. The use of the herbicide dicamba is an example. The development of soybean cultivars tolerant to this herbicide is an important strategy developed with a view to new alternatives in the control of weed plants resistant to herbicides, with a consequent increase in crop productivity.

This new technology, supported by biotechnology, once made available to Brazilian farmers will represent yet another tool in the battle to protect productivity. However, it brings with it, imperatively, the need to master application technology. Not that it wouldn't be the case for other products, but because incorrect use could be seen in the damage to some sensitive plants, such as soybeans that are not tolerant to the herbicide.

When in possession of dicamba salts and formulations that present a low risk of volatilization, farmers must select appropriate spray tips, in addition to drift-reducing adjuvants, that generate the smallest possible quantity of fine droplets, employ spray volumes that allow good coverage of the target, even when working with extremely thick droplets, and pay attention to weather conditions during applications. High temperature, low relative humidity and strong winds are enemies of safe spraying of any agricultural pesticide.

Another point that is often relegated to the background in the daily routine on farms refers to the cleaning of tanks and components of the sprayers' hydraulic circuit. Herbicide residues impregnated in tanks can cause injuries to sensitive plants in subsequent applications, to the point of interfering with productivity. Therefore, creating a cleaning routine is and will be increasingly fundamental. In the case of dicamba, research has already proven that 3 rinses of the tank with water are enough to clean it, although additives are also being tested to make this procedure faster and safer.

Without a doubt, the future will bring us new challenges in crop protection, but application technology will be present to help farmers achieve their goals, in a sustainable way. Training operators and regulating, calibrating and evaluating sprayers will become increasingly part of farm routines.

By João Paulo Rodrigues da Cunha, professor at the Federal University of Uberlândia