corn field


Of all major food crops in Minnesota, corn — or maize — is the only native of the Americas. Maize was domesticated about 5,000 years ago in tropical Mexico, and cultivation spread among Native American tribes. Unlike other grasses it produces separate male (tassels) and female flowers (silks) and can adapt quickly to different environments.

Until about 1915, farmers collected seed for the next crop from their best plants. They graded the cobs following University guidelines that even included plans for the wood rack used to sort the cobs. While this open pollinated seed was somewhat customized to local conditions, the plants matured unevenly and the stalks often broke and fell over. U of M agronomists released exceptional open pollinated varieties in the early 1900s as they developed the science of controlled pollination — leading to hybrids — along with breeders at other land grant universities in Illinois, Iowa, Missouri, and Nebraska. Of all major food crops in Minnesota, corn — or maize — is the only native of the Americas.

Corn culture.

In 1970, molecular biologists discovered where on the chromosome the genes responsible for protein synthesis are located. In 1975 U of M geneticists were also first to regenerate corn from tissue culture.

Soil testing near corn field.

University soil scientists analyze runoff from row crops to determine what tillage systems best protect soil. The results influence how farmers plant, till, and harvest crops; lead to improved water quality; and impact the marine life in the Gulf of Mexico.

Efforts from 1915–20 identified "inbred" lines possessing specific, desirable traits that could be combined to create hybrids for particular regions and uses. In 1920 U of M corn breeding efforts expanded by adding staff at a branch of the University's Agricultural Experiment Station in Waseca. Earlier maturing hybrids — for northern regions — were tested on the St. Paul campus, while researchers at Waseca developed higher yielding, full season hybrids.

Experimental hybrid corn varieties were released by the U of M in the late 1920s, as researchers conducted two landmark studies defining the trait of genetic "combining ability" and how important it was to hybrid success. The best in the reservoir of superior inbreds were used over the next 50 years to create almost 100 "Minhybrids" adapted to Minnesota's extreme conditions. U of M researchers have long worked for farmers through the Minnesota Corn Research and Promotion Council.

From dry sandy areas up north to moist organic soils and a longer growing season in the south, the University varieties set performance standards for a rapidly developing private seed corn industry.

Field workers on break from corn harvest - historical.

Field workers take a break from a 1930s harvest at Waseca, center of much of the University's corn research.

Maturity TestingCorn maturity map.

In 1939 the state legislature approved maturity testing of all seed corn sold, an early consumer protection act for farmers. Five zones were established from north to south, with the U of M Agricultural Experiment Station designated as official testing agency. Researchers plant and test hybrids in each zone and compare days to maturity (30 percent ear moisture) to a reference hybrid. Seed companies provide this rating on each bag of seed sold.

Pigs in pen.Corn Production and Uses

The United States provides about 80 percent of the world's corn. Minnesota, on the northern fringe of the Corn Belt, ranks fourth in the U.S.

Corn has over 3,500 uses, falling into several broad categories:

  • 50% Animal feed — cattle, hogs, poultry
  • 23% Exports — almost all for livestock feed
  • 10% Reserves — provides a supply in bad crop years
  • 8% Sweetener — candy, and over half of all non - diet soda
  • 5% Ethanol fuel — reduces pollution
  • 4% Direct human consumption — thickener in processed foods

Researchers Evaluate Corn for:

  • Early season vigor
  • Resistance to stem & leaf diseases
  • Insect resistance
  • Plant height
  • Number of ears per plant
  • Ear length
  • Number of rows of kernels
  • Root systems & standability
  • Date of maturity
  • Yield performance

Signs with seed companies.50 Years of U of M Research Shared Globally

From 1950 to 2000 the U of M released to commercial seed companies more than 100 inbred lines and germplasm — the specific, unique characteristics of a plant. Traits captured in germplasm solve specific challenges: disease resistance, natural protection from insects, drought tolerance, or efficient use of nitrogen. The genetic information is developed by traditional and modern breeding techniques, including molecular genetics. Hybrid seed contains germplasm from many sources, built upon decades of public and private research.

A major analysis of corn grown two decades ago showed that U of M germplasm was used in hybrids growing on 21 percent of U.S. corn acres. Two of the inbred lines ranked first and fourth of all corn parents in the country.

Corn being processed.

A U of M genetic engineering effort created high lysine, an essential amino acid, germplasm. The goal is to improve human and animal nutrition in parts of the world where maize is a major component of the diet.

University accomplishments in corn breeding are recognized globally. In the 1950s and 60s Minnesota breeders worked with the United Nations Food and Agriculture Organization and shared Minnesota corn germplasm worldwide. These efforts have attracted many international students. After working on genetics, disease, insect, or soils research, they have gone on to establish or strengthen research programs worldwide.

Continue on to Oats

U of M Corn Releases

99 Hybrids1920s-1970s
98 Inbred Lines1920s-2000
3 Popcorn Hybrids1930s
12 Open Pollinated1893-1920s
Top Varieties
Minn. 13
NW Dent
Silver King
Pearl Flint
Dakota White
Golden King
Golden Jewel
Minn. 23