Story Behind Corn Domestication

Maize is also known as corn. Talking about the history of maize begins at the inception of human agriculture, nearly about 9,000 years ago. The agriculture land that was cultivated by farmers now known as Mexico, farmers their initiated the journey of domesticating the maize when they first started to figure out which kernels (seeds) to plant.

They noticed that all the plants have different characteristics. Some plants had the tendency to grow bigger in size or some may have a color difference while some kernels were easier to grind or would taste better. The farmers saved the one needed to harvest in the next season and the chain followed till the kernels with desirable characteristics were achieved. This process is generally known as artificial selection or selective breeding. Through this Maize cobs became bigger in size with time, eventually taking on the modern maize form, with more rows of kernels. The identification of maize's ancestors or may be called as wild part remained an unsolved question for many decades. While other grains such as rice and wheat have general wild relatives, not a single wild plant was identified that looks like maize, with soft, starchy kernels arranged along a cob. Thus its evolution was generally liked to occur steadily by minor changes throughout the time. Whereas the study of genetics had put some light on the interesting question, scientist finally observed and reached to a conclusion that corn's wild ancestor is grass called teosinte. Teosinte is not much similar to maize, especially if you compare its kernals to that of the corn. But when it comes to the DNA level, the two are strangely alike. They have a suitably similar arrangement of genes and the similar number of chromosomes. Also, maize-teosinte hybrids can be reproduced naturally if teosinte will be cross-breeded with modern maize varieties. In the late 1930s, Scientist named Beadle studied the process of teosinte-maize hybrids and displayed that the chromosomes of maize and teosinte are highly compatible to each other. In the process he discovered large numbers of teosinte-corn hybrids and observed the characteristics of the new hybrids. When the basic law of genetic inheritance was applied, Beadle notified that only 5 genes were held responsible for the most-observed differences between teosinte and a modern strain of maize. Later with the help of some modern techniques, another group of scientists observed the DNA from teosinte-maize offspring and found the same 5 genes responsible for the difference.

By: Anuja Arora

Content: https://www.sciencedaily.com/releases/2018/12/181213141524.htm