Soy in Brazil is driven by technological innovations

Soybeans (Glycine max (L.) Merrill) have a center of origin in northeast China (between 45 and 50º N), a latitude that, in the Americas, corresponds to Patagonia in the south and, in the Northern Hemisphere, to the north of the United States and southern Canada. There are quotes, without due historical basis, that soy would have been used as food in time immemorial. The literature does not mention any trace of the legume at any Neolithic archaeological research site in northern China, and leading scholars agree that only dates after 1100 BC can be accepted as accurate in the history of soybeans.

 The introduction of soybeans in the West occurred at latitudes similar to the center of origin, starting in Europe in 1712. The first report on soybean cultivation in the United States is from 1765. Although slowly, soybeans expanded in the country, requiring investment in research that they led to technological development that resulted in productive and disease-resistant cultivars, in a production system adapted to different North American production conditions.

 In 1882, Gustavo D'Utra carried out the first soybean cultivation in Brazil. An undertaking that failed because the genetic material, developed for cold or temperate climates, did not adapt to the conditions of Bahia. In 1891, cultivars were tested at the Campinas Agronomic Institute (IAC-SP). However, the successful trajectory of commercial soybean production began in Rio Grande do Sul, from 1920 to 1940. Before that, in 1901, professor Guilherme Minssen, from the then Escola Superior de Agronomia e Veterinária, currently linked to the Federal University of Rio Grande do Sul (UFRGS), had started research with the legume. 

 Transformation through science

 In the 1970s, the RD&I effort gained increasing dimension and sophistication, involving a multitude of actors, both public and private. The first challenge was to produce cultivars for the subtropical and tropical conditions of Brazil, to replace those imported from the United States, which were developing reasonably well in the south. It turns out that the demand pressure from international trade indicated that soy would not just be confined there.

North American cultivars did not grow properly here, making trade unviable. The core of the problem was floral induction, determined by the length of the day (photoperiod), a genetically controlled characteristic. It was only after introducing the long juvenile period attribute that soybeans were able to safely expand to other regions.

During this period, the plant does not flower, even if photoperiod conditions are present. Only in this way is it possible for the plant to grow and develop, form biomass in an adequate volume and express high yields. This discovery represented a paradigm shift on a global scale, as it had never before been possible to successfully cultivate soybeans in tropical regions.

The challenge of the cerrado

 
The key had entered the lock, but opening the doors to the vast cerrado for soybeans required more scientific research, as the soils are acidic and have low fertility. It was necessary to provide feasible formulas for correcting chemical characteristics to provide ideal nutritional conditions. Currently, there are specific fertilizer recommendations for each region and for different levels of productivity.

 
Nitrogen is one of the essential chemical elements for plant development. Meanwhile, if its addition to the soil occurred in the form of chemical fertilizer, its cost could make soybean production unfeasible or, at least, severely limit it. A network of scientists and institutions developed the technology for symbiotic nitrogen fixation in soybeans, which involved identifying strains of Bradyrhizobium japonicum - the bacteria that fixes nitrogen from the air and transfers it to the soybean plant - to formulations suitable for use in tropical conditions.

 
One of the initial bottlenecks was the production of high quality seeds, in adverse conditions, under high temperatures and inadequate rainfall. A complex system was designed, with favorable conditions for processing and preserving the seeds, so that the producer would receive them within the required quality standards, in particular vigor and germination capacity.

 
Soil preparation based on the use of plows and harrows, with intense soil disturbance, suitable for the Northern Hemisphere, meant an economic and environmental disaster in Brazilian tropical conditions, quickly eroding the surface layer of agricultural areas. This was the motivation for the development of the direct straw planting system, currently used in around 90% of Brazil's cultivation area, which allows the cultivation of soybeans and other grains, without frequent soil disturbance.

The system allows the incorporation of organic matter, the fixation of a considerable part of the carbon absorbed by plants and the formation of a straw cover on the soil, with beneficial effects on the microfauna and microflora of the soil, as well as contributing to thermal control. and maintaining humidity.

  
A soybean for Brazil

 
In temperate or cold climates, although it is host to several pests, soybeans are not as subject to stresses that limit their productivity as in tropical climates. To resolve the issue, technologies were developed and, without a doubt, the most important one was to incorporate genetic characteristics of tolerance or resistance to viruses, bacteria, fungi and nematodes into cultivars.

 
However, the diversity of pests and the intensity of their infestation and damage required technological innovations to overcome phytosanitary threats. Invasive plant management systems were developed, culminating in the incorporation of soybean's genetic resistance to broad-spectrum herbicides, through transgenesis. The same tool was used to incorporate resistance to defoliating insects, inserting a gene into the soybean genome that expresses a protein lethal to these insects.

 
Soybean pest management combines knowledge of the biology and ecology of pests and their damage with control techniques, which include crop management, biological and chemical control, as well as concepts such as economic level of damage. More aggressive species of fungi, such as the one that causes soybean rust, are controlled with a set of techniques that encompass the sanitary void - the prohibition of soybean cultivation for a period of 60 to 90 days during the off-season -, a monitoring network , diagnosis and warning and the recommendation of more efficient control measures.

 
Adequate soil management, correction of its profile, soil porosity and microstructure, organic matter content, absence of compacted layers required technologies that allowed an ideal environment for the growth of soybean roots and the rhizosphere and that also favor beneficial microorganisms.

 
Throughout the history of soy in Brazil we have seen double pressure. The first, from the international market, requiring greater production each year. The second, the need to produce with the least possible impact on the environment. In addition to the technologies exposed - developed from the perspective of lower environmental impact - some techniques specifically meet these requirements. For example, the crop, livestock and forest integration system (ILPF) consolidates this concern, as well as the intensification of agriculture, with the sequence of two or three grain harvests (for example, soybeans, corn, cotton or beans), or even from a pasture that occupies the soil in the off-season, which reduces the pressure for area expansion.

The trajectory does not end in the present. We always have new challenges, requiring permanent dedication from scientists to break barriers and break paradigms, always with a focus on the sustainability of soy production systems in Brazil, based on the best science and technology.

By Decio Luiz Gazzoni; Member of the Sustainable Agro Scientific Council (CCAS), Agricultural Engineer and researcher at Embrapa Soja