There is something about sodium chloride (NaCl) that causes humans the world over to indulge in the delicious salty products. For example, I ate a large burrito last night for dinner at one of my favorite restaurants and when I got home feeling like I was about to explode, my appetite was miraculously renewed at the first sight of the salty Tostito Chips my roommate was munching on in our living room. Amazingly, between the two of us, we were able to finish the bag even though we had both just eaten dinner.

This love for salty products is not limited to American culture by any means; the Chinese use soy sauce, South Asians use various sodium filled curries, and Americans use the world’s favorite NaCl enhancer: ketchup. Although this delectable topping bares little resemblance to its main compound, tomatoes continue to make up a large proportion of the ingredients of most ketchup and are therefore extremely important to this industry.

Lucky for Heinz and the billions of ketchup lovers around the world, a new study conducted by a scientist at the Cold Spring Harbor Laboratory and his colleagues at the Hebrew University in Israel have discovered a gene that gives hybrid tomatoes a miraculous increase in their yield.

The discovery was made when the research team was searching for genes that could act as a catalyst to boost the vigor of plants with a condition called heterosis.  It’s not a disease. Initially studied by Charles Darwin, heterosis is the tendency for hybrid varieties of crops tend to be more vigorous and have higher yields than their non-hybrid counterparts. After an extensive study, the researchers identified a hybrid variety of tomato with dramatically increased yield due to a gene called florigen.  Interestingly, researchers found that for florigen to increase yields, one copy of the gene had to be mutated.

Florigen instructs plants when to start making flowers and thus, when to begin producing fruit. Dr. Zach Lippman says of the study’s findings,  “It’s the Goldilocks concept, what we find is that to maximize yield, you can’t have too much or too little florigen. A mutation in one copy of the gene results in the exact dose of florigen required to cause heterosis.”

Interestingly, the scientists were able to observe the gene’s heterosis effect in two very different climates, that of Israel and of New York City. This finding adds a level of robustness to the conclusions of the study that eliminates any doubt that environmental factors have a role in the higher yield observed in this hybrid tomato variety. The researchers hope to explore whether florigen has a similar effect on heterosis in other crops. If so, this would have a dramatic effect on the agricultural industry.

Discussion Question: Given that florigen has been found to regulate heterosis in other plants, do you think the researchers will be successful in their quest to find more robust hybrid varieties of other crops? Why or why not?

News Article: http://www.sciencedaily.com/releases/2010/03/100328170239.htm

Scientific Article:http://dx.doi.org/10.1038/ng.550