Wednesday, September 14, 2016

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. 


  1. So when breeding plants that have superior traits compared to the parents do the parental traits eventually disappear? Meaning can we no longer produce a plant that is similar to the parent one? (even though it wouldn't be much use since its not as efficient)

  2. In theory, yes. Those traits of the parents eventually disappear, like how they would in normal evolution, and the traits of the filial generation plants would be more prevalent.