October 9, 2018

History of How Brazil became so Important in Soybean Production

Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.

I know the following article has nothing to do with the current soybean production estimates in South America, but as Brazil is poised to surpass the United States in soybean production, I thought it would be interesting to review the history of how Brazil became such an important soybean producer. The following history is from researcher Decio Luiz Gazzoni, who is an agronomist with Embrapa and a member of the Scientific Council for Sustainable Agriculture (CCAS).

According to Gazzoni, soybeans (Glycine max (L.) Merrill) originated in northeastern China at latitudes of 45° to 50° north latitude. In North America, those latitudes would equate to northern United States and southern Canada. In South America, those latitudes would equate to Patagonia. Soybeans were first introduced into the west at latitudes similar to where soybeans originated in China.

The first soybeans were introduced into Europe in 1712 and in the United States in 1765. The first soybean variety was introduced in Brazil in 1882, but the cultivar was not adapted to the tropical climate of the state of Bahia in northeastern Brazil. In 1891, soybeans were tested at the Agronomic Institute of Campinas in the state of Sao Paulo. In 1901, research on soybean production was started at the Federal University of Rio Grande do Sul in far southern Brazil and from there, soybeans were slowly introduced into the state of Rio Grande do Sul between 1920 and 1940.

Development of Tropical Soybeans - It wasn't until the decade of the 1970's that soybean varieties were developed for the tropical and subtropical climates of Brazil. Soybean varieties developed in North America did not perform adequately in Brazil. The heart of the problem is that soybeans are photoperiodic and they start to flower and set pods based on the length of the nighttime. If soybeans developed in North America were planted in tropical Brazil, they would start to flower at a very early stage and the plant would never get large enough to develop an acceptable yield.

It was only after plant breeders incorporated a longer juvenile period of development into the varieties that soybeans could then be produced in other regions of Brazil. During this juvenile period, the plant does not flower even though the day length should trigger flowering. Only after the longer juvenile period was incorporated could the soybean plant develop enough biomass before flowering to insure adequate yields. This was the key for enabling soybeans to be grown in a tropical environment such as Brazil.

Overcoming Infertile Soils - Even though soybeans could now be grown in the tropics, there were other obstacles to overcome before soybeans could be grown profitably in the cerrado region of central Brazil. The cerrado soils were very acid, highly weathered, low in fertility, and they had high levels of aluminum, which can be toxic to non-native plants. Research had to be done to identify the nutrient deficiencies and the best method to correct the deficiencies.

Another problem is that soybeans fix their own nitrogen in a symbiotic relationship with rhizobium bacteria, but that bacteria was not present in the cerrado soils. A group of scientists had to develop a system of nitrogen fixation suitable for the cerrado soils and the hot and humid climate of central Brazil.

Speaking of climate, scientists also had to develop systems for seed production and seed storage suitable for the very hot and humid environment of central Brazil. They had to develop a system for seed storage that would insure adequate germination and seedling vigor for planting the subsequent crop.

No-till Soybean Production - The traditional seedbed preparation of plowing and disking, which was common in North America, turned out to be a disaster in Brazil, especially in the hilly terrane of southern Brazil. The farmers in southern Brazil would prepare their seedbed ahead of the first summer rains. Unfortunately, the first rains can be torrential downpours which resulted in a tremendous about of soil erosion.

That was the motivation for the development of no-till soybean production where the soybeans are seeded into existing vegetation or plant residue. The vegetation or plant residue kept the soil covered eliminating nearly all of the soil erosion. The subsequent weed control was accomplished by the use of herbicides. This system not only prevents erosion, it also improves the organic content of the soil, the soil fertility, the soil structure, and the water holding capacity of the soil. Today, approximately 90% of Brazil's soybean production is no-till.

Increased Disease and Insect Pressures - Soybean production in Brazil also faces different and more intense disease and insect pressures compared to more temperate climates. Additionally, in central Brazil there is no "winter weather" that can help to control insect populations from one growing season to the next. That was the motivation for the incorporation of the Bt gene into Brazilian soybeans to help control insects. Soybean rust is a very severe soybean disease and scientists worked with producers to introduce a 90-120 day soybean-free period to help control the spread of soybean rust spores from one growing season to the next.

New Crop Rotation Systems - Brazilian scientists have always worked to increase soybean production while at the same time trying to minimize the impact on the environment. One of the promising systems going forward is the system for integrated crop, livestock, and forestry production. This is a long term rotation of two or three years of grain production followed by several years of pastures and beef production or even fast growing trees for pulp production. The ultimate goal of this system and other rotation systems is to increase productivity on existing land thus reducing the pressures for additional land clearing.