Gardening: Why non-GMO seeds matter, to me

Surprised about the level of concern about genetically modified food

  • May. 21, 2015 5:00 a.m.

I noticed that when this year’s seed racks were delivered, most, if not all of them had banners declaring them free of genetically modified seeds – the reason being that consumers want nothing to do with such products.

Then the new pineapple-flavoured ‘Aloha’ strawberry arrived and almost every single potential buyer took the time to ask me if they were genetically modified – which they are not, as it is just a hybrid.

This level of concern surprised me, but I was still happy to see people making informed choices.

That said, I think it might be a good idea to review what constitutes a hybrid, cultivar, variety or clone – or other terms sometimes mistaken for genetically modified.

A hybrid is generally a cross of two compatible species. This can occur in cultivation or naturally.

Cultivars are usually vegetatively-reproduced natural mutations that are discovered in gardens or in the wild.

Natural varieties or subspecies are found in the wild and survive without any human intervention; these just have traits (flower colour, leaf shape) that differ from the species.

Clones or tissue-cultured plants are simply reproduced by using their own genetic material, so there is no actual tinkering with the natural DNA.

This brings us to genetically modified plants, which do have the DNA altered and are not found in the wild, except as escapees.

These have not gone through the filter of millions of years of biological evolution, so we have no idea how they will ultimately impact the environment.

They are generally modified to resist insect pests and herbicides and include corn (93 per cent of U.S. crop), cotton (96 per cent of U.S. crop), soybean (94 per cent of U.S. crop), canola, sugar beets, rice, potatoes, squash and the ‘Arctic’ apple.

Personally, I think you should just say no to GMOs, but if you are interested in knowing more:

• Once released, GMO plants cannot be controlled – escaped GM canola plants (Brassica napus var oleifera) have been detected from Japan to Canada, but in North Dakota two such escapees were found to be herbicide resistant, even after naturalizing. Such plants would be capable of cross-pollinating with compatible noxious weeds such as field mustard (Brassica napa) and creating an herbicide-resistant offspring. (1)

• GM crops are responsible for herbicide resistance – weeds will eventually develop a resistance when only one herbicide (glyphosate) is applied to Roundup-ready GM crops, which has already resulted in 21 resistant weed species. This has forced some farmers to resort to secondary herbicides or, additional sprays, which some have been estimated to be equal to 25 per cent increases per year. (2)

• They often harm more than the target pest – genetically modified Bt corn pollen has been shown to kill 44 per cent of Monarch butterfly larvae in controlled experiments (and in the wild), with the remaining larvae being about half the size of those not exposed to the Bt pollen. This is a serious problem because much of the Monarch’s natural habitat is adjacent to the corn crops in America’s heartland. (3)

• Genetically modified material is being absorbed by the human body – Bt toxins (linked to GM corn) were found in the blood of pregnant women, their babies and also non-pregnant women in the eastern townships of Quebec. In 2003, 90 residents of a Filipino village became seriously ill when the newly planted GM corn started bearing pollen – all lived within 100 metres of the field and Bt contamination was found in the blood of 30 individuals. (4)



(1) Genetically Modified Crop on the Loose and Evolving in U.S. Midwest, by David Biello, Scientific American, Aug. 6, 2010.

(2) 10 Reasons to Say No to Genetically Engineered Crops and Food (

(3) Monarchs and Bt Corn: question and answers, by Martin Rice (,  June 14, 1999).

(4) Dozens Ill & Five Deaths in the Philippines, by Dr. Mae-Wan Ho (, June 2, 2006).