Editors’ Note: In the latest post in HistPhil’s forum on the Green Revolution, Marci Baranski explains the special place wheat played within the  Green Revolution, and why that history might not necessarily work as a model for future programs of agricultural development.

Very recently, wheat overtook rice as the highest acreage food crop in the world. The global spread of wheat is without a doubt linked to the mid-century efforts of the Rockefeller Foundation (RF) that led to the Green Revolution. In my dissertation, I explored how the Green Revolution legacy has affected agricultural scientists’ views towards climate change adaptation in wheat, particularly in India. From my research, I found RF’s success with wheat in Mexico and India was based on two critical factors: the physiological aspects of wheat and its ‘wide adaptation,’ and the institutional innovations in international agricultural research led by the RF and also taking place in India in the mid-1960s.

Despite the RF’s role in popularizing new wheat varieties and technologies around the world, none of the RF’s international efforts started with wheat alone. The RF’s first international agricultural programs focused in Mexico (1943, maize, wheat, and beans), Columbia (1950, maize, wheat, and livestock), India (1954, maize only), and Chile (1955, maize, wheat, and livestock). Rice did not become a focus until the later 1950s. In 1954, the RF started the Central American Corn Improvement Program, a cooperative between El Salvador, Honduras, Nicaragua, Costa Rica, and Panama, and by 1956, the RF was testing maize varieties in several more countries in South America and also in India, Indonesia, and the Philippines. RF scientists led their international cooperative experiments with maize, and in each case, wheat followed a few years behind.

But by 1965, it became more and more clear that wheat would be the main international focus of the RF’s agricultural program headquartered in Mexico (then called the International Center for Corn and Wheat Improvement). RF scientists found that their wheat varieties maintained high yields in the Middle East and India, while maize did poorly abroad. Even in Mexico, the RF’s new wheat varieties were incredibly popular, while hybrid maize adoption floundered. So while wheat and corn had equal priority in the RF’s Mexican program, and still do today, in the Centro Internacional de Mejoramiento de Maíz y Trigo (International Maize and Wheat Improvement Center), why was the wheat program so much more successful?

Let’s go back to 1944, when Norman Borlaug was hired into the RF’s Mexican Agricultural Program to work on wheat. His initial task was to develop wheat varieties resistant to rust disease, which was a persistent problem in Mexico. But Borlaug couldn’t just transplant rust-resistant varieties from the U.S. and Canada. These were poorly adapted to Mexican conditions due to different lengths of daylight and seasons. Borlaug and other RF scientists realized that improved varieties for the semi-tropics needed to be derived from gene pools in the tropical, rather than temperate zones.

Around 1945 Borlaug began alternately growing wheat generations between north and central Mexico, which was later called ‘shuttle breeding.’ In the winter, Borlaug planted wheat in the Sonora region of Mexico—a coastal, irrigated region near sea level and at 28˚ N latitude. Then he would select the best offspring from that season and plant them in Toluca (near Mexico City), which was at 18˚ N latitude, had a high altitude, and had heavy rainfall and a higher prevalence of pathogens. Under Borlaug’s supervision, the RF released new rust-resistant spring wheat varieties in 1949, and by 1957 these new varieties constituted 90% of Mexican wheat acreage.

Simultaneous with his shuttle breeding efforts, Borlaug coordinated a network of international wheat scientists and began testing his wheat varieties against local wheat varieties all over the world in the early 1960s. Borlaug found that some of his varieties—especially those derived from the varieties Mentana (Italy), Florence-Aurore (Tunisia), and Gabo (Australia)—had consistently high yields across locations. Keep in mind that this research was all on tall wheat, and Borlaug had not yet incorporated the trait for semi-dwarfism that he is now known for.

Borlaug was rightfully excited about the “surprisingly broad adaptation” of his wheat varieties. Scientists generally define broad, or wide, adaptation as a plant type that has high yields throughout diverse environments. While Borlaug was not the first scientist to discover wide adaptation, he brought it into mainstream agricultural science. The conventional wisdom of plant breeding in the early 20^th century was that crop selection should occur in the target environment, creating varieties with specific adaptation to the local conditions. Borlaug’s wheat research program—and more so his ‘missionary zeal’—turned convention on its head.

Prior to Borlaug’s research, many scientists presumed that foreign agricultural assistance programs necessarily must have a limited geographic scope. In his 1961 oral history, George Harrar, then-president of the RF, stated:

“Unfortunately, most scientific advances most directly benefit the particular geographic area in which they originated. This is especially true in the agricultural sciences. Of course, many basic principles are discovered which can be useful on an international front, on a broad front, but the application of those principles depends upon local climatic conditions and on many other factors.”

Contrasting the RF’s experience with wheat, maize varieties required specific adaptation to local conditions, prohibiting the wide spread of one or a few varieties. RF staff Delbert Myren wrote that, “In order to obtain hybrids that yield better than local native varieties, it has generally been necessary to develop them for specific climatic conditions.” The RF had this experience in both Mexico and in India, where their hybrid maize improvement program was not particularly successful, but provided the template for the later Indian wheat improvement program.

Borlaug had been in a position of international leadership for wheat research throughout his tenure in Mexico. During this time, he made wide adaptation a core pillar of the RF’s international wheat program. To Borlaug, wide adaptation was emblematic of his program’s global reach and ability to affect radical agricultural change. Borlaug argued that wide adaptation was not only tenable, but also desirable as a plant-breeding goal. Through his publications, correspondence, and lectures, he influenced agricultural scientists around the world. Beyond this paradigm-shifting endeavor, however, Borlaug had a very mission-oriented reason for promoting wide adaptation: he wanted to modernize agricultural production in developing countries, and thought that widely adapted varieties were the most likely way to accomplish this.

I have not touched in the blog post on the many problems that stemmed from Borlaug and the Indian wheat program’s focus on wide adaptation. But even without getting into those criticisms, I leave the reader with this note:

What worked for wheat, and for some extent rice, in the Green Revolution should not be a model for future research. The wide adaptation of wheat has been unparalleled in any other crop, due to the particular physiological aspects of spring wheat. Borlaug was lucky that spring wheat was so adaptable, but most crops are not. Even within the species of wheat, Borlaug could not develop a widely adapted winter wheat. Further, in many parts of the world, food security is not constrained by genetic advances, but rather location-specific issues of agronomy and distribution. Though the idea of a centralized research program was appealing and successful for the Green Revolution in wheat, future research and philanthropic efforts must recognize that agriculture is by nature a local and culturally specific enterprise. A modern Green Revolution must by nature be different than the previous one, and we should not constrain possible future innovations to a narrow set of mid-century political and scientific precedents.

-Marci Baranski

Marci Baranski is a Presidential Management Fellow and climate change specialist at the U.S. Department of Agriculture. She completed her PhD in Biology and Society in 2015 at Arizona State University under the direction of Professor Ann Kinzig. Her dissertation work was supported by the Rockefeller Archive Center grant in aid and the NSEP Boren Fellowship.