GARDENING: Meet sweet ‘Maggie’ — a new non-GMO gourmet tomato |

GARDENING: Meet sweet ‘Maggie’ — a new non-GMO gourmet tomato

Curt Swift
Free Press Gardening Columnist
Meet "Maggie," a sweet new non-GMO tomato which should be hitting local farmers' markets next season.
Submitted photo |

A new red cherry tomato called “Maggie” will find its way into the U.S. market this year. You should look for this new non-GMO tomato at your local farmers’ market as it has a much higher sugar content than other tomatoes; up to five times as much with a BRIX reading of between 5.5 and 6.5. (Brix is a scientific measurement used by the food industry to determine sugar amount.)

This gourmet specialty tomato will be a great snack for those who don’t typically eat their vegetables. Approximately 1.5 inches in diameter and highly resistant to Fusarium wilt, this tomato has been favored throughout Israel and Europe for several years. The company creating this sweet-snack tomato, Hazera Genetics, is known for its non-GMO sweet cherry tomatoes; one of its selections, “Summer Sun” sold for $350,000 for a kilo of seed in 2009 to European growers. That is about $1 per seed. “Summer Sun” is a round yellow tomato about 1.3 inches in diameter with an even higher Brix reading of six to seven.

While the disease resistance of “Maggie” is quite limited, if you have disease pathogens in your soil, you could rotate your tomato crop to a field or garden plot where the soil-disease pressure is considerably less, or you could graft “Maggie” onto a tomato root stock with resistance to the disease organisms inhabiting your soil. While the root stock does not confer its disease resistance to the scion grafted to it, researchers have reported increased tolerance to viruses and other diseases when susceptible tomatoes are grafted to resistant root stocks.

Grafting, therefore, might help improve tolerance with the tomato spotted wilt and curly-top viruses our tomatoes have to endure in this area. In addition to improved disease resistance, many growers experience a 20-30% increase in production. From the time you plant the seeds to obtain the root stock and the scion (in this case “Maggie”) until your grafted plants are ready to be put into the garden is about five weeks. This is the same age your non-grafted tomato plants should be when planted outside. If you are interested in learning more about grafting tomatoes (and peppers), Ohio State University recently published a pictoral guide that focuses on the grafting of these vegetables using the cleft and splice methods. This reference also provides a list of root stocks, their disease resistance, and where you can obtain the seed. A search using the keywords “ohio state university grafting guide” will take you to the grafting guide.


Agricultural Research Service scientists recently reported thousands of compounds determine the flavor of tomatoes but two components play key roles: the amount of sugar and the amount of acid. Most of us already knew that but what is interesting is the “flavor” in a tomato is the interaction and ratios of sugars, organic acids, and volatile compounds derived from amino acids, lipids and carotenoid precursors.

Precursors are compounds that come before another molecule is biosynthesized and carotenoids are produced by some bacteria and plants to protect them from excessive levels of light and absorb energy for photosynthesis. Researchers found a positive correlation between sweetness and flavor. The sweeter the tomato, the more flavor it contained. While the amount of acid varied only slightly in the varieties tested (from 0.2% to 0.64%), there was a wide variety in sugar content (3.4% to 9%). Fructose and glucose were the major forms of sugar found in tomatoes.


Tomatoes originated in Peru, Chile, Ecuador and Mexico, but were brought to colonial America through Europe. During the early 20th century, breeders crossed the early cultivated varieties with wild species to make the tomatoes we have today. In the process they inadvertently added genes with unintended consequences. The phenomenon, known as “linkage drag,” is a common problem and is a particular challenge for tomato breeders because so many of the tomato’s key horticultural traits originated from wild relatives where the undesirable genes originated. Genes responsible for premature ripening, misshapen fruit and other characteristics are just a couple of the undesirable traits plant breeders want to avoid when developing new cultivars.

The tomato genome sequence, published in 2012 by ARS scientists and collaborators, is allowing breeders to use molecular markers to identify and lock in tomato genes that are responsible for desired traits such as flavor and lock out those traits considered undesirable. Some of the latter are latent and could appear at any time during the development of new cultivars. It took plant breeders six years to develop “Maggie” and if some of those latent genes had appeared during the process, you wouldn’t have “Maggie” at our local farmers’ markets.

Dr. Curtis E. Swift is a retired horticulture agent with the Colorado State University Extension. Reach him at, 970-778-7866 or check out his blog at He owns Swift Horticultural Consulting and High Altitude Lavender.

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