GMO Purple Tomato

There does seem to be some truth to the anthocyanin providing protection to the plant itself. On average my purple veggies seem to fair better against pests.

I see that in Kohlrabi, sweet potatoes, kale,
and definitely lettuce. I can’t grow green lettuce without spray, but the bugs don’t touch my outredgeous lettuce. But it’s not sweet. There’s a bitterness to it for sure.

High lycopene tomatoes have been around for about 60 years using gene b^og and a high pigment modifier. I grow several varieties with high lycopene. I also grow varieties such as Stommel’s 97L97 which has 40X more beta carotene (turns into vitamin A) than normal tomatoes. If you want tomatoes that are like taking a multivitamin, you can certainly grow them. Doublerich has twice as much ascorbic acid (vitamin C) as normal tomatoes.

I think much of the interest in high anthocyanin tomatoes is in the novelty aspect. As I noted previously, the entire anthocyanin biopath is present in tomato but is not expressed. All it takes is a promoter to turn on the biopath.

- TGRC look for “B” and see the og modifier.

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In breeding for anthocyanin does that come at the expense of lycopene?

Seeing a GM variety for a novelty market and home gardeners seems like a turning point doesn’t it? Or is this just the first well publicized example?

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I think the appeal is in the novelty. Purple tomatoes are cool. We have Midnight Snack Tomatoes, which are a half purple half red cherry tomato, and whenever someone comes over, its usually the first thing they notice in the garden. Tastewise (at least cooked) it tastes them same as our Everglades Tomatoes. Color is a good selling point because it makes your product stand out, especially in an industry like gardening where a lot of people just do it for fun. The nutrition and everything else are just tagalongs that just happen to happen when you turn a fruit purple.

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I guess the good thing is, it’s nice to see people interested in the nutritional content of their produce. If it’s true we’ve spent the last few decades breeding nutrition out of our food, then maybe things will start going in the other direction.

For lycopene, there is a sequence where prolycopene is converted to lycopene which is converted to beta carotene. So if the gene for beta carotene is present, it is produced at the expense of lycopene.

Anthocyanin is an entirely separate biopath from lycopene therefore it is possible to have a fruit with both lycopene and ancyocyanin. Caveat that any chemical produced by a plant has a biological cost to the plant therefore producing both lycopene and anthocyanin will impact overall plant performance. Also, anthocyanin usually covers over lycopene so that you can’t see lycopene even if it is there. Green stripe gene (Green Zebra tomato) affects both lycopene and anthocyanin expression so it is possible to have fruit striped with both colors.

Also, anthocyanin can cause red, blue, purple, or black expression. I have not verified, but the GMO purple tomato is probably expressing petunidin.

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I can grow lettuce without sprays but I am often times planting and harvesting before the bugs come out. Lettuce is nice because where I live I can start it around April 1st and get my first crop around May (maybe before may) and it will regrow and hold well until it is time to plant my annual herb garden like basil or cilantro. I have not had pests on either my purple passion or my green asparagus. I am only in my 3rd year though. Asparagus has honestly been an easy crop for me overall though. There is a few crops that have been easy for me to grow and those being garlic, asparagus, squash, lettuce and basil. Generally those things tend to not require much more than watering once a week. Lettuce just has to be grown at a certain time for climate and that is going to change from place to place as seasons change.

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