It efficiently transforms energy from the sun into stored chemical energy in its seeds. Some varieties are no more than two feet tall. Others grow to over 20 feet. Most of the corn now grown in the central Corn Belt of the U. What all varieties share is a basic arrangement of roots, stalk, leaves, seed structure and the arrangement of the reproductive parts of the plant.
On normal modern varieties, the seed will germinate and grow quickly. About 55 days after it begins to grow, the plant will produce a tassel at the top that has five to 20 branches. At this stage, each ear contains around 1, ovules or potential kernels of corn. These are "potential" kernels because they require the male part pollen to fertilize them before they can grow into a full kernel. Attached to the top of each ovule is a strand of "silk" that grows out of the protecting husk to the top of the ear.
Sometime after the 60th day, millions of grains of pollen are released and float down to the silks. When a grain of pollen hits a silk, it divides and travels down the silk to fertilize the ovule or egg. Confession time. When this was first descried to me, I thought it meant they had to somehow sex the seeds before planting them I was an Animal Science major, ok!?
However, as we just learned above, corn plants are both male and female! The goal is for only pollen from the male rows to pollinate the ears in the female rows. Well, we basically let the male plants keep their male parts the tassel and remove them from the females. Before the female rows begin pollinating, large machines make several passes through the fields to cut and pull as many of the female tassels as possible. This process leaves the male tassels untouched while eliminating the undesired female tassel.
This is where a staple Midwest job comes in for many school-aged kids. For about three weeks each summer, thousands of kids across the Midwest walk every row of female plants and pull any tassels that remain. Field inspectors will also come out to make multiple observations and counts throughout the season to determine if enough tassels have been removed to fall within standards set for purity. All of the work that goes into detasseling is still mind-boggling to me.
The preparation, organization, and timing has to be just right or else an entire field could be lost. I realize now that successful detasseling of the female rows is essential to ensuring we produce the hybrid we intended. Once the detasseling season has ended, the male rows are eliminated since they have completed their male-y duties of pollination. This ensures ears on the male plant which have presumably been fertilized by pollen from the male tassels are not harvested.
In the picture below, you can distinctly see blocks of four rows and a gap where the male row once stood. Males are also often planted around the seed corn field as a barrier to block pollen from neighboring corn fields. This also increases the amount of desired male pollen in the area. Everything described above is very high level and was learned in a whirlwind of eighteen days. My goal is to keep learning and in the process I hope you learn something too. Pretty cool!
To learn about how inbred corn lines are produced, read my post here! August 24, at PM. August 25, at PM. Wow, Hannah! I had no idea. Chips also have lower amounts of vitamins and minerals and provides a low level of dietary fiber.
While low in vitamins and minerals, air popped popcorn is also low in fat, sodium and calories as well. Most of the calories come from carbohydrates. Popcorn is low in dietary fiber. In the late s and s, the demand for corn in the United States was high.
People ate corn as food, canned it to have in the winter, and ground it into flour. Additionally, livestock farmers were becoming more interested in corn as feed for cows.
Farmers needed to grow more corn, but the farmland available for growing corn was already in use, so farmers' only option was to grow more corn per acre. Sometimes with the help of state agricultural extension workers, farmers grew different varieties of corn, selected the best seed, and grew plants from that seed the next year. Unfortunately, the next year's crop was often variable, and yields still didn't increase.
Despite farmers' best efforts to develop the highest quality seed, yields were flat. Farmers were stuck. Examine the graph of US Corn Yields between and Describe the trend in corn yields during that time. Corn yields stayed stable during that time period. Despite the stagnant yields, thousands of years of farming knowledge offered a possibility for the corn farmers.
Farmers knew that crossing different species or varieties sometimes resulted in more vigorous offspring. The mule, useful because of its strength and endurance, was a cross between a horse and a donkey. There were also examples of crossing donkeys with other closely related species.
A similar concept was observed in plants. Archeological evidence shows that Native Americans regularly planted two different strains of corn together in some areas so that they would cross-pollinate and produce more vigorous offspring. That traditional knowledge was supported and expanded upon by scientific experiments through the s and into the s. Several scientists found greater positive benefits in cross-pollinated plants than in self-pollinated ones.
One such scientist was Gregor Mendel, who published his results in the late s. Mendel investigated the inheritance of traits in pea plants, which he chose because he could easily control their pollination.
In addition to outlining the basic principles of inheritance, Mendel noted that hybrid plants — those that were the result of a cross between two different inbred lines of "true-breeding" parents - tended to grow much more robustly than the self-pollinated plants. This Punnett square shows the cross between an inbred line of small pea plants tt and an inbred line of tall pea plants TT. Mendel observed that all the offspring tended to be as tall as or taller than even the taller parent.
Charles Darwin, best known for his ideas about evolution by natural selection put forth in On the Origin of Species , also published a book on plant breeding in — The Effects of Cross and Self Fertilization in the Vegetable Kingdom.
In this book, he shared data from plant crosses and provided more support for the idea that self-pollinated plants tended to make less vigorous, less pest-resistant, lower-yielding offspring than plants that are hybrids, or crosses between two strains. In short, there was growing evidence that for some plants, hybrids tend to be more robust.
Darwin's work had a strong influence on many scientists, including William Beal, who, in the s, studied pollination control as a way to minimize the negative effects of inbreeding in corn. Mendel was just working out patterns of inheritance; scientists didn't yet use the terms alleles or genes.
The late s into the early s were times of great change in our understanding of traits and inheritance. At this same time, corn farmers in the US had a problem. They had tried to increase yield by saving their best seeds, but they weren't able to maintain the increased quality and yield they sometimes found.
They had a challenge that careful experimentation in the emerging areas of inheritance could possibly address: how could farmers maximize and sustain the effects of cross-pollination to increase their corn yields? Darwin, Beale, and others noted both the negative impacts of inbreeding in corn plants and the positive impacts of outbreeding due to cross-pollination.
Creating corn varieties with desired traits, however, required connecting the pollination work findings with the recently rediscovered work of Gregor Mendel - the fundamentals of inheritance and ideas about what we now call alleles. In the early s, George Shull applied Mendel's ideas to understanding inbreeding and outbreeding in corn and conducted experiments that led to a hybrid revolution. At the same time, Edwin Murray East, a young chemist, conducted a similar set of experiments and developed a parallel set of ideas.
Watch the following video to learn more about their experiments. Cornell plant breeder Professor Margaret Smith demonstrates making crosses with corn. Crosses between inbred lines produce hybrids and a boost in yield. In , George Shull was the first to clearly describe the heterosis concept. This idea changed the quest for desirable corn varieties. Corn breeders, as Shull suggested, gradually shifted their search from existing lines to looking for the best hybrid combinations.
Henry A graduated from Iowa State College in and started corn breeding in a foot-byfoot garden behind the family home in Des Moines in This was soon followed by more extensive breeding — though still tiny by modern standards — on a nearby farm owned by his uncle. A single-cross hybrid called Copper Cross developed by Wallace — which was a cross between an inbred from the variety Leaming and another from Bloody Butcher known for its dark red kernels — was entered in a newly created regional varietal performance trial.
The hybrid yielded first in and its seed was produced on one acre of land near Altoona Iowa under contract with George Kurtzwell of the Iowa Seed Company. Copper Cross was not a commercial success because of the low seed yield. Indeed, it was only sold for one year, and Wallace and partners shifted quickly to double-cross hybrids. But, as the first true hybrid corn sold in the US Midwest, the historical fame of Copper Cross is assured.
The corn program moved to newly purchased land at Johnston, north of Des Moines, at about this time. As well as being a visionary and entrepreneur, Henry A. Henry A became U.
Secretary of Agriculture in thus ending his direct involvement with Pioneer. He later served from to as vice-president of the United States under President Roosevelt. Among other accomplishments as secretary and vice president, Henry A played a critical role in the creation of the Rockefeller-funded corn and wheat improvement program later, CIMMYT in Mexico. Wallace attracted some outstanding people to his team including a farm boy and recent ISC graduate, Raymond Baker, who joined Pioneer in Baker became head of corn research in I had the rare privilege of meeting Baker as well as author Bill Brown, then vice president of research and later to become Pioneer president, when I interviewed for a research position at Johnston in The interview occurred in a nondescript three-story red-brick building on the Johnston property that was then the headquarters for the Pioneer corn research program — a far cry from the expansive Pioneer research campus that exists there today.
My interviewers also included Don Duvick and Forrest Troyer, two outstanding corn breeders and industry leaders, and good contacts in the years to follow. Such a rare opportunity for me even though I did not take the offered job.
An entrepreneur extraordinaire, Roswell Garst, persuaded Wallace in to let him produce Pioneer seed at Coon Rapids Iowa, about 50 miles northwest of Des Moines, and sell it in western Iowa and states further west. Thomas was a minor player in the venture and his share was soon purchased by Garst.
This turned out to be a financial gold mine for Garst. Pioneer Canada had a similar beginning with the initial business being that of a farmer and businessman who later sold out to the Johnston-based company.
I also had the privilege of visiting Roswell aka Bob Garst and his various businesses in Coon Rapids in about Garst was a very colourful, aggressive and highly opinionated character who had became nationally famous for hosting Soviet leader Nikita Khrushchev during his visit to Iowa. Bob Garst would have made Donald Trump look like a wallflower. George Sprague, a USDA breeder at Iowa State College based on early inbreds with superior stalk quality reference here , 2 a huge pre-release hybrid testing program with many locations all across corn-growing regions of North America, and 3 a unique three-replicate testing process introduced by Don Duvick, then head of corn research.
I recall Don discussing this this over lunch in Chicago in about I tried to persuade him to go with two reps at standard and two at plus — advise which he rejected. He obviously made a brilliant decision that paid off hugely for the company. Pioneer became the North American leader in corn seed sales in , and I think it has been there most of the time since. The company changed its name to Pioneer Hi-Bred International in and went public in This coincided with a major company reorganization and expansion beyond North America including a new corn-breeding program in France.
Pioneer was first traded publicly on the New York Stock Exchange in The association had the goal of ensuring good seed quality for its members — an apparent problem at the time. Tom Roberts was hired as county agent and as the manager of the association.
The association also hired Charlie Gunn who figured prominently in the corn-breeding program to follow. In , Roberts and Gunn invited Henry C. Roberts and Gunn began corn inbreeding in secret that summer but did not tell the association directors until five years later.
This was done, apparently, to keep a local competitor in the seed business from knowing what they were doing. The first production of commercial seed was in ; a major drought that year meant only bushel of hybrid seed was produced on 75 acres. Not discouraged, they produced 14, bushels on acres in and 90, bushels in The genius of Roberts and Gunn was in producing large quantities of hybrid seed right from the beginning and advertizing aggressively, especially in the farm magazine, Prairie Farmer.
These advertizements resulted in requests for purchases from farmers all across the US Midwest, including maturity zones much different from northern Illinois. Ralph St. John, a prominent corn breeder Purdue University, was hired to serve as a corn breeder for DeKalb, focusing on longer-season maturity zones. Seed production facilities were established in Nebraska, Iowa and Indiana in The first DeKalb corn was sold in Ontario in Four million acres of the Midwest were planted with DeKalb hybrids in The hybrid, DeKalb A, introduced in became hugely popular in the central Cornbelt, with more than , bushels of seed sold in That was followed by XL45, an earlier maturing hybrid that proved highly successful during the s — with its fame enhanced when Clyde Hight used it to become the first Midwest farmer to average more than bushels of corn per acre on a substantial acreage.
DeKalb was the largest US seed corn marketer from the mid s until the s when it was surpassed by Pioneer. The seed portion was spun off and named DeKalb Genetics Corporation in The DeKalb Corporation also had extensive investments in non-agricultural ventures including petroleum.
On a personal note, I was very close to DeKalb for several years during the s when we combined to test some of my ideas for corn inbred selection I was a crop physiologist with the University of Guelph at the time in their commercial breeding system in northern Illinois. I was never a paid consultant though DeKalb did sponsor a couple of my graduate students. This ended when there was a major change in DeKalb research management — triggered by a major loss in market share to Pioneer — and I left the University of Guelph to work for a farm organization — both occurring in the early s.
Lester Pfister, born in , quit school at age 14 to farm near El Paso, Illinois, and thereafter developed a system for yield-test comparisons of open-pollinated varieties. In that era, yield-test comparisons were very uncommon; farmers generally chose seed for the following year based on ear characteristics — usually as they hand-harvested the ears of their own crops — but also in purchases of seed ears from neighbours. Farmers would commonly pay more for seed still on the ears — versus shelled — so they could see what the ears looked like.
From this beginning, Pfister developed a variety called Krug Yellow Dent that became very popular in central Illinois. He began inbreeding Krug in Pfister struggled with near financial ruin caused by the Depression and droughts in and but persevered, producing 37, bushels of hybrid seed for sale in , generally using inbreds provided by Holbert at the USDA station at nearby Bloomington.
Pfister also benefitted from some national publicity generated by a feature story in Life magazine that claimed he was the inventor of hybrid corn. He used this publicity very skillfully to expand his business.
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