Plant Science: Hybrid Vigor Characterized

Scientists have determined that the breeding of plants within their own species naturally produces plants that are larger and more fertile than those in their parent generation. When organisms have stronger and more superior qualities than their parents, it is called heterosis. Within agriculture, heterosis is important because it allows plants to have larger yields and improve their vigor. Heterosis contributes to the improvement of crops and is important because of the growing global demand for food. Understanding the vigor of plants enables us to understand how viable they are, how likely they are to survive and pass on equally strong or stronger offspring.

Research has been conducted to determine any genetic aspects of heterosis. The scientists couldn't narrow down specifics of the genomics; however, grouped regions of several genes have been highlighted in the study. It was determined that the genes associated with heterosis act similarly to dominant gene alleles. To show a substantial change in plant qualities, the plant must have at least one copy of a variant, or complete dominance. The dominance is compared to a spectrum where some qualities are partially positive or partially negative dominant, depending on the effect of the genomics on the plant. 

These different aspects of dominance help when mutations are involved. They have no effect on the plant when present from only one parent. Also, the quantity of proteins produced by the genes affects the plants. This is called dosage sensitivity. While both the dominance spectrum and dosage sensitivity do not affect plants identically, they generally benefit the plants. Scientists have speculated why heterosis does this and have considered it to only be a part of natural selection. 

I feel like even though heterosis has roots within natural selection, since evolution is the demonstration of genetic change over time, heterosis also has genetic causes. With genetic modification, I believe we can properly improve the vigor of hybrid plants. We just haven't pinpointed specific genes that are responsible. The study of heterosis and plant science has a practical application to our world. We have a global demand for food, especially with the rising population rates. By understanding heterosis and how it affects the vigor of plants, we are able to understand how to provide strong, viable food sources for ourselves and future generations. 

New Study Looks into Genetic Explanation for Heterosis in Corn

 



For over a hundred years, farmers used the concept of heterosis to increase crop yields. To take the most advantage of increased productivity, farmers cross two distinct lines of corn to produce a variety that performs much better than either of the two original strains. Much works has been done to study what lineages produce various types of corn, such as field corn and sweet corn. However, for all of the work that has done with corn hybrids, the genetic mechanism that makes this all possible remains a mystery – until now.

According to Science Daily, a research team comprised of individuals from the University of Bonn, Iowa State University, and the Max Plank Institute has proposed a genetic reason as to why heterosis works. Through state-of-the-art genetic sequencing technology, the researchers discovered genetic fingerprints suggesting that hybrid plants have more active genes than purelines. The increase in the amount of active genes allows hybrid plants to be more productive.

Perhaps the most exciting part of the article is its application to the real world. As food prices – especially corn prices – rise higher every day, there would be a great worldwide benefit if the researchers’ work could be used to produce corn crops with higher yields. Not only is corn used for human consumption, but it is also used for animal feed and biofuels as well. The researchers’ findings has the potential to have a major impact in the global economy.