Wednesday, August 11, 2010

SUPERWEEDS!

So there's this study everybody's been talking about over the last few days, where some researchers found some genetically modified canola plants growing in the wild in the U.S. And I feel like I have to talk about it a little bit. So I will.

What is canola? Canola is a variety of oilseed rape (Brassica campestris or B. rapa), produced for making cooking oil, animal feed, and other products. It's preferable to regular rape because: the name is less off-putting,1 its glucosinolate levels are significantly lower, making it more suitable for animal and human consumption,2 and it was bred to grow especially well in Canada, though that last one is pretty much only preferable if you live in Canada. In the U.S., North Dakota and Minnesota also grow some canola.

Canola field blooming in Saskatchewan. Photo by Wendy, via Wikipedia.

As with a lot of crops, much canola currently being grown is of genetically modified varieties which resist the herbicides glyphosate (Monsanto's) or gluphosinate (Bayer's). American readers are fairly likely to know glyphosate by the trade name Round-Up.

So what the study (conducted by University of Arkansas scientists) found was that -- brace yourself -- along the sides of roads where genetically-modified, herbicide-resistant canola seed is frequently transported, one can find genetically-modified, herbicide-resistant canola plants growing. I'll give you a moment to pick yourself up off the floor.

The bigger news, though, is that some of the plants researchers found had genes for resistance to both glyphosate and gluphosinate. Now, Monsanto sells canola seeds which resist glyphosate but not gluphosinate, and Bayer sells seeds which resist gluphosinate but not glyphosate, but nobody sells seeds which are resistant to both, because doing so would mean violating one or both companies' patents. Which means that the plants are breeding, along the sides of these roads, and a few lucky plants have managed to snag both resistance genes.

So, wow. Plants of the same species, growing next to one another along the side of the road, can cross-pollinate one another and shuffle their characteristics about. Who could possibly have guessed?

Cue the anti-GMO crowd, who point to this as proof that genetically-altered crops can escape into the wild and breed SUPERWEEDS!, which for some reason is always said like that, in bold all-caps, with the exclamation point. They predict that these SUPERWEEDS! will next cross-pollinate other species, species to which they're not even related, and then we'll have even more SUPERWEEDS! until such point as genetically modified organisms ruin every single thing in the world for all time. Or something like that. I'm a little fuzzy on what the actual problem is that they're seeing.

Canola seeds. (Photo: public domain. Via Wikimedia Commons.)

Now, it's possible that there's something to this story that I've missed, and GMO canola really is going to kill us all, but here's why I'm not seeing this as a problem, or even as news:

1) It's not news because this has been seen already. This is apparently the first time it's been spotted in the United States, this escaping of transgenes into the wild, but this is old news to Canada, Japan and Australia. So for anybody to be making a big deal out of it now just because it's happening in the U.S. is a little silly. It makes perfect sense that it would happen, we've seen it happen elsewhere, now it's happened here. So what.

2) Genes don't actually jump species that easily in the wild. I mean, it happens, but part of the reason why we can say that this plant is a Strelitzia and this plant is a Phalaenopsis is because they're genetically distinct enough that they won't breed with one another. The odds of an herbicide-resistance gene from a Brassica being transferred to dandelions or goosefoot is pretty tiny.3 And even if it were, the new plant could be sterile, so you get one lonely hybrid plant that lives its life without setting any seeds and then is never seen again. Or it may just be bad at competing with other plants. Or it could get eaten by a cow. Winning the lottery doesn't protect you from getting struck by lightning.

3) The existence of "wild"4 plants with transgenes doesn't actually make it more likely that weeds are going to pick up these herbicide-resistance genes. Plants containing these genes were already growing in large fields all over, next to substantial numbers of uncultivated weeds. We could argue about whether that's a responsible arrangement or not, but either way: if the transgenes were going to spread, they were already doing so, so this discovery is small potatoes next to that.

4) These "wild" plants only have one advantage over non-GMO plants: that they're resistant to herbicides. If we stop using these herbicides because they're no longer effective, then these canola plants no longer have an advantage over other plants they're in competition with.5 If they no longer have an advantage, then they're likely to be outcompeted. If they're outcompeted, they die, and the problem goes away on its own.

So even if the transgene for glyphosate resistance spread to every single plant on earth, all that would happen is we'd stop spraying glyphosate. Which we should possibly be doing anyway. This is much less an emergency for the environment and much more an emergency for the herbicide manufacturers.

5) As much glyphosate as people were using, some plant was going to evolve glyphosate resistance sooner or later. We may have sped up the process, but herbicides and pesticides never last forever: glyphosate and gluphosinate wouldn't have either.

So.

I'm more or less indifferent to genetic engineering, personally. I don't see it as being that much different from what people were doing before. Whether a crop plant's genes arise through hundreds of years of selection and breeding, or get borrowed, fully-formed, from a jellyfish, platypus, or ostrich, really doesn't matter that much to me, as far as whether or not I'd eat or grow the plant.

Having said that, I'm still deeply worried about the legal and regulatory issues around GMOs: the patents, the suing of organic farmers because the GMO-using farmers can't keep their pollen to themselves, the Terminator genes, and so forth. Monsanto's done some pretty crooked things already; there's no reason to think they won't do more in the future. This doesn't invalidate the technology, but we might question whether we should trust Monsanto with it. A country with a functioning, representative democracy could probably do something about this situation, but I don't live in one of those, so I'm pretty much stuck with crossing my fingers and hoping Monsanto doesn't manage to ruin anything we can't live without.

Well I'm not the world's most masculine man,
but I know what I am and I'm glad I'm a man: so's Canola.
Ca- Ca- Ca- Canola, Ca- Ca- Ca- Canola.
(Photo: Canola field in Temora, New South Wales. Photo by John O'Neill, via Wikipedia.)

There are two points I hope readers take away from this. The first is, I'd like you to remember that it matters a great deal what the transgenes have been introduced to do. Genes aren't automatically safe because genetic engineering has happened; they're also not automatically dangerous. BT corn6 worries me a little bit, even though the evidence so far seems to be saying that it doesn't pose a serious threat to non-target organisms like monarch butterflies. I worry anyway because I can see how the BT gene might get out and protect weeds from being eaten, someday, or because I can see how large amounts of BT-producing pollen blowing around in the environment could have consequences for other organisms. Don't think consequences are likely, but I can see how it could work, and I wouldn't necessarily be surprised. But this? Herbicide-resistant canola? Not so much.

The second thing is that I would take it as a personal kindness if everybody would stop calling them SUPERWEEDS! The word "superweed" only has one purpose: to scare people and make them easier to manipulate. It's a dumb, dumb word, and more than being dumb, it's dishonest. We have way, way too many words like that now.7 Please stop using it.

I'd be willing to settle for ironic-only usage, if that would be easier on everyone.

References:

James and the Giant Corn (who is responsible for me realizing I had enough to say on the subject to make a blog post out of it, and from whom I may have stolen a couple tiny little points)
New York Times
80 Beats
NPR
Grist (anti-GMO)
International Business Times

-

1 Canola" is an acronym of sorts, standing for "Canadian oil, low acid." Originally this was a trademarked name, but has since become generic for low-acid, low-glucosinolate rapeseed oils. The original name of rape is totally innocent, and comes from the Latin rapum, meaning turnip, to which rape is related.
2 Glucosinolates are bitter-tasting compounds found throughout the mustard family (Brassicaceae) and a few other families. If you dislike cauliflower, brussels sprouts, broccoli, or cabbage, glucosinolates are probably why.
3 Why? Well, it's complicated, but at least some of the reason is that in order for plants to cross with one another, their chromosomes have to have most of the same genes, in mostly the same order, on more or less the same number of chromosomes. The less-related two plants are, the more genetic changes have accumulated, and the less able they will be to cross.
4 I don't think "wild" is exactly the right word here. They can grow in places where they're spilled along the side of the road, and apparently they can also cross and have progeny which also live along the side of the road. But roadsides aren't pristine habitats to begin with, so they're hardly ruining anything we hadn't already ruined.
5 In fact, they're likely to be at a disadvantage, if anything. Long story, no time, but maybe someday.
6 Corn which has been genetically modified to include a gene for an insect-killing protein from a bacterium, Bacillus thuringiensis. Among the advantages of BT corn: it doesn't have to be applied to the plant because it's already built-in, it doesn't lose potency during the growing season, and it only affects insects that try to eat parts of the plant. A possible serious disadvantage: pollen, which is spread far and wide through the air, counts as a plant part.
7 It's somewhat out of fashion now, but the best example is probably terrorist. It has a real meaning, and occasionally you still see people using it correctly, but most of the time, if somebody starts talking to you about terrorists, that's a sign that someone wants you to turn off part of your brain and be afraid.


23 comments:

Liza said...

Brilliant, mr_s, thank you! I've been pestering James for months to guest write exactly this type of post for my readers. I love it! James, haha, I know you're reading this, shoot me an email one of these days!

James said...

I completely agree with you on the misleading nature of superweeds. I always come away from the stories that use that name a lot with the sense I am supposed to think that somehow by spraying herbicides on fields of GMO crops, farmers are going to create new weeds that make life harder for organic farmers, which doesn't make any sense since organic farmers aren't using those herbicides in the first place.

Glad to hear I was able to spark the inspiration for this post, it was a great read.

Liza, if I could write like mr_s I'd have gotten that post to you long ago.

CelticRose said...

Good grief! Not 5 minutes after reading your appeal to sanity, I ran into this: http://www.cactusjungle.com/blog/2010/08/10/franken-genes/

I don't think I'll be reading his blog anymore.

Paul said...

People are totally looking at the issue incorrectly. If we have a bunch of herbicide-resistant brassicas growing randomly, the likelihood that they would carry with them brassica pathogens and/or attract brassica pests WHERE THEY SHOULDN'T BE and cross-infect/infest will balloon. Fortunately, brassicas aren't a huge food source like rice, wheat, or corn are. So no, it's not a huge mythic deal, but it's an unwise path to follow.

Sixwing said...

Butbutbut teenage mutant superweeds!

mr_subjunctive said...

CelticRose:

Disagreement on one point doesn't invalidate the whole blog. Lots and lots of people picked up this story, on both sides of the issue, and I think everybody used the word SUPERWEEDS! at some point. I don't think this study is cause for alarm, and I'm a little surprised at how many people do, but whether it is or isn't, Cactus Blog is still worth visiting.

Paul:

True though that is, that would still be more or less true of non-GMO escapees, which I assume have been happening since before there were GMO plants. Non-transgenic plants would be, obviously, a lot easier to control with herbicides, but herbicides were never our only option for controlling weeds. At least in this case they all seem to be growing in convenient, easily-accessible patches along roadsides, where they could be burned, pulled up, sprayed with different herbicides, or what have you.

There's also the matter of other Brassicaceae-family plants (particularly garlic mustard) being out there already, in large quantities, which could be providing a reservoir of canola pests even if nobody had ever dropped a GMO canola seed.

Peter said...

Celtic Rose-
All I did on my blog was post an excerpt from an article. I do that a lot. As opposed to Mr. Subjunctive who tends to get into more details on his blog.

I have my own opinion about the significance of this article, which I did not share. If you would like a bit of that, I am adding a comment on my original post.

http://www.cactusjungle.com/blog/2010/08/10/franken-genes/

Greensparrow said...

Great piece. Should the organics people be happy glyphosate resistance is getting around -- so evil conventional farmers wont use it any more?
By the by -- I do find some GM gene escape concerning. I think if the Bt gene got into wild teosinte populations, for example, it could have serious ecological repricusions. But round-up ready? Who cares.

Diane said...

Agreed on the FUD associated with Evil Scientists And Their Frankengenes. As an Evil Scientist, I like to think we're trying to good things, e.g. feed the world, learn how plants work, etc. I rarely rub my hands together and say "Mwah-ha-ha" in the lab. Rarely, but not never. Because it's fun.

One point though, regarding hybridization: I read the abstract for the presentation, and Brassica napus is an allotetraploid. This makes fertile hybrids more likely because polyploidization allows recovery from hybrid sterility. She writes that it "hybridizes spontaneously with more than 10 native and naturalized species in the U.S." However, the case is not made that this is a bad thing w/r/t the resistance genes. Unless the plants escape into someone else's cash crop and cannot be eradicated, and therein lies the potential problem, and that's why it's good that people are studying topics like this. If B. napus is not an invasive weed, some other transgenic crop might be.

The problem is not the study, it's the press release, or maybe more correctly it's what the media have done with the press release, assuming a release was actually written. It's not even a published study, it's a 15-minute grad student talk at ESA! This study is officially not worth talking about until it's published. Words like SUPERWEEDS are media inventions; the science is objective, and no worthwhile scientist would use such a word except with understood "" around it. I wonder how this woman feels about the coverage her work is receiving. I myself would be freaking out if my Botany talk became gloom and doom news.

mr_subjunctive said...

Diane:

A lot of guys ignore the laugh, and that's about [having] standards. I mean, if you're going to get into the Evil League of Evil, you have to have a memorable laugh. (ref.)

I hope I didn't give the impression that a scientist was responsible for "SUPERWEEDS!" Though this sort of thing appears to be spreading: I just fifteen minutes ago saw someone tweet a reference to pesticide-resistant "SUPERBUGS!"

Curious about which ten other species canola would readily hybridize with. Does it say? Are any of them weeds already?

Rainforest Gardener said...

This was an excellent post, and though you specifically told me what two things to take away from this, all I can thing of is "SUPERWEEDS!" What a silly name.

James said...

@Diane I try to laugh evilly in lab at least once per day.

I knew Brassica napus was an allotetraploid of B. rapa and B. oleracea* but I'm not sure I understand her point about allotetraploidy making it more likely canola will produce fertile hybrids with other species. If anything hybridizing a tetraploid with a diploid relative should produce completely sterile triploids in the next generation like bananas or seedless watermelons, shouldn't it?

*For those who don't know the names, these species give us turnips + various asian vegetables vegetables, and broccoli/cauliflower/brussels sprouts/cabbage/etc respectively.

Pat said...

I think "feral" was the word for which you were groping, rather than "wild".

Brassica rapa has weedy varieties itself. We certainly have some very similar mustardy weeds in the UK. http://www.springerlink.com/content/g25r31667v477287/

Don't Kudzu and Japanese Knotweed count as superweeds?

Thanks for reminding me that I didn't finish watching Dr Horrible. Must have been something good or very bad to distract me from that.

Pat said...

Brassicas are sluts. They will even produce non-sterile hybrids with other genera with different numbers of chromosomes. Full paper here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2707916/

I just need to go and sit somewhere quiet and dark while my brain readjusts its connections.

Paul said...

"not sure I understand her point about allotetraploidy making it more likely canola will produce fertile hybrids with other species."

That's a given that a diploid and a tetraploid will produce (sterile) triploids? I didn't realize there were triploid brassicae at all. I know random 'accidents' happen all the time, but as a species, I never knew such a thing in that family existed.

mr_subjunctive said...

Pat:

I'd be willing to let kudzu, Japanese knotweed, water hyacinth, Caulerpa taxifolia, etc. be called superweeds. I don't remember ever seeing the word used for any natural species, though; it's always the hypothetical offspring of wild plants and GMO plants.

Also, I couldn't make it entirely through the papers (bit of a headache), but the Brassica hybrids, though easily produced, don't sound very threatening: many plants, but only three survived, they were all smaller than the parents, one was totally sterile, and two were half-sterile. I mean, point taken: they can hybridize, and they hybridize easily enough that sooner or later they really could hit on a winning combination and become a SUPERWEED! So maybe I'm a little bit alarmed, then. Not sure.

Paul:

Well, that's the point, that triploids wouldn't be expected to be fertile, and would die out after a generation, whenever they were formed. I don't think James meant that triploid Brassicas had actually happened.

If I read it correctly, the second paper Pat links says that Isatis indigotica (2n=14) and Brassica rapa (2n=20) formed viable hybrids by dropping most of the Isatis chromosomes, instead of the textbook,
"7 chromosomes from Isatis + 10 chromosomes from Brassica = 17-chromosome Isatis x Brassica hybrid."

Which if the hybrids are free to just ignore inconvenient chromosomes from other plants when it suits them to do so, then obviously that changes the expectations for what's possible here.

James said...

@Paul

Diploids have two copies of each chromosome and pass one copy of each chromosome on to their offspring. Tetraploids have four copies of each chromosome and pass two copies along to their offspring. So by definition, the offspring of a mating between a diploid and a tetraploid should be triploid (3 copies of every chromosome). Triploids are, generally speaking, sterile, because three copies of each chromosome is not divisible by two.

And if the hybrids are sterile, they'd die out after a single generation, and they wouldn't be around for you or I to have heard of.

Mr. Subjunctive wrote post on triploid sterility a few months ago:

http://plantsarethestrangestpeople.blogspot.com/2010/03/geneticist-phalaenopsis-cvv-part-i.html

Zeï said...

Brilliant post.

Luebella said...

Like I always say... Nature wins...

Every time.

When are we dumb humans ever going to learn???

Jordan in Oregon said...

So if Monsato is so sue-happy that they've bankrupted and otherwise ruined many a farmer's life over their so-called 'patent infringements', then when do Bayer and Monsato start suing the $%^# out of eachother?

mr_subjunctive said...

Luebella:

Well, but don't forget, we kicked smallpox's ass.

And wooly mammoths.

And passenger pigeons.

And thylacines.

And dodos.

And Chinese river dolphins.

And aurochs.

The list goes on.

True, nature may get us back even worse, but it's self-defense: nature started this fight. See: malaria, cholera, typhus, tetanus, dengue fever, yellow fever, polio, pertussis, hepatitis, smallpox, anthrax, trypanosomiasis, pneumonia, influenza, botulism, trichonellosis, measles, rubella, rabies, mumps, syphilis, leprosy, elephantiasis, gonorrhea, chlamydia, etc. And those are just the bad infectious ones.

Jordan in Oregon:

Well, I'm not them, so I don't know, but I'd assume they'll start suing one another when they think the playing field is unlevel enough that they're certain to win. No fun suing someone who can defend him/rself.

Tigerdawn said...

I would like to request that crabgrass be added to the list of SUPERWEEDS! please.

digitalemur said...

Oh my GOD, thank you so much for writing this, because it's the rant have been waiting for since I first studied transposons in college, and it's a brilliant piece of GMO debunking. I could put pieces of this together, but not the whole thing.

And, man, yeah, cry my a river if people find reasons to stop using freaking glyphosphate. That's strong stuff. It has its uses-- we never found a better way to control rampant multiflora rose in cattle pastures when I was a kid on a dairy farm, but we never used it when we didn't have to. But oh man, we handled it with great fear, because my dad was a pesticide application trainer too, and he was really really cautious about how we used everything.

So thank you, Mr Subjunctive, I will now pimp you out to all my friends for this wonderful post. (I'm not forgiving you for the Lola parody, though.)