A Race to Save the Orange by Altering Its DNA
July 28, 2013 8:32 AM   Subscribe

The disease that sours oranges and leaves them half green, already ravaging citrus crops across the world, had reached the state’s storied groves. To slow the spread of the bacterium that causes the scourge, they chopped down hundreds of thousands of infected trees and sprayed an expanding array of pesticides on the winged insect that carries it. But the contagion could not be contained.

With a precipitous decline in Florida’s harvest predicted within the decade, the only chance left to save it, Mr. Kress believed, was one that his industry and others had long avoided for fear of consumer rejection.
They would have to alter the orange’s DNA — with a gene from a different species. (SLNYT)
posted by yeoz (117 comments total) 20 users marked this as a favorite
 
They would have to alter the orange’s DNA — with a gene from a different species.

It's not like they're using the DNA from a chimpanzee.
posted by orange swan at 8:45 AM on July 28, 2013 [1 favorite]


Or a swan.
posted by thatone at 8:46 AM on July 28, 2013 [5 favorites]


I was half hoping that it would be a gene from a phosphorescent jellyfish, because I can never find oranges in the dark when I need to.
posted by sherief at 8:54 AM on July 28, 2013 [25 favorites]


A similar situation arose for bananas in the 1950s. In a way it would be cool if the standard food oranges got wiped out, forcing a massive societal rejiggering of what "orange" tastes like as a new type was settled on.
posted by Tell Me No Lies at 8:55 AM on July 28, 2013 [3 favorites]


Strong to the finish 'cause I eats me oranges.
posted by jet_silver at 8:55 AM on July 28, 2013 [2 favorites]


i say it's spinach and i say to hell with it
posted by pyramid termite at 9:01 AM on July 28, 2013 [5 favorites]


Genetically altered oranges will end up as a SyFy Original Movie monster. Mark my words.
posted by delfin at 9:02 AM on July 28, 2013


In the heat of last summer, Mr. Kress gardened more savagely than his wife had ever seen.

...
posted by Tell Me No Lies at 9:03 AM on July 28, 2013 [30 favorites]


This is what worries me most about the "choose better genes for your kids" story from the other day. It's not that better genes are somehow worse than worse genes, but rather that identical genes are less pandemic-resistant than diverse genes, and when we've aimed for "better" via artificial selection the past we've typically managed to pass far too close to "identical" along the way.
posted by roystgnr at 9:04 AM on July 28, 2013 [7 favorites]


So the takeaway here is that DRM-loaded foodstuffs weren't making a lot of headway, so we need to manufacture some good ol' product-selling panic?
posted by DU at 9:06 AM on July 28, 2013 [5 favorites]


no, the takeaway seems to be that american orange crops are in danger of being wiped out and this may be the only way to save them
posted by pyramid termite at 9:09 AM on July 28, 2013 [16 favorites]


Don't be silly pyramid termite. These are genetic engineers we're talking about, who do you think created the disease?
posted by Tell Me No Lies at 9:11 AM on July 28, 2013 [3 favorites]


Gosh, who could have predicted monocultures would be such a bad idea?
posted by entropicamericana at 9:11 AM on July 28, 2013 [40 favorites]


These are genetic engineers we're talking about, who do you think created the disease?

do you have a citation for that?

(it seems to me that monoculture has a lot to do with the problem)
posted by pyramid termite at 9:14 AM on July 28, 2013 [1 favorite]


Lemme put it another way: Do you normally accept the word of Florida businessman lobbies without looking for alternatives? Or is it just when it's a story in the always-speaks-truth-to-power NYT?
posted by DU at 9:18 AM on July 28, 2013 [4 favorites]


It's not like they're using the DNA from a chimpanzee.

How about a flounder?
posted by weapons-grade pandemonium at 9:20 AM on July 28, 2013 [1 favorite]


no one's stopping you from posting links that prove your take on the controversy - seems to me the person who doubts the NYT story is the one who should be providing alternative sources
posted by pyramid termite at 9:21 AM on July 28, 2013 [4 favorites]



Don't be silly pyramid termite. These are genetic engineers we're talking about, who do you think created the disease?


Charles Darwin! Quick get the orange hating bastard off the £10 note!
posted by srboisvert at 9:21 AM on July 28, 2013 [2 favorites]


These are genetic engineers we're talking about, who do you think created the disease?
do you have a citation for that?


There is extensive documentation here.

(it seems to me that monoculture has a lot to do with the problem)

Indeed. See my banana link above.
posted by Tell Me No Lies at 9:23 AM on July 28, 2013 [1 favorite]


China didn't have genetic engineers in the 1800s, did it? Anyway, stop your worrying. Australia is without citrus greening. Australia can supply the world's uranium and OJ.
posted by de at 9:24 AM on July 28, 2013


I wonder if there's some lonely citrus tree somewhere in the forests of Borneo or China, that is quietly resistant to this disease, and unknown to science. Hard to believe there are only this many varieties of citrus and no more.
posted by the man of twists and turns at 9:25 AM on July 28, 2013 [1 favorite]


There is extensive documentation here.

Maybe you meant to link to something else, because this is a link to TVTropes. Also there are only two entries under "Real Life" one of which is a thought experiment and one of which is about medicine men.
posted by en forme de poire at 9:25 AM on July 28, 2013 [3 favorites]


Australia can supply the world's uranium and OJ.

Now available in our convenient new two-in-one container!
posted by Thorzdad at 9:26 AM on July 28, 2013 [6 favorites]


I have to provide links that there's more than one species of orange available? Or are you looking for a link that shows that the one in current use is optimized for shipping and shelf life and that handing over control of our food supply to corporate powers is worth it to save this one?
posted by DU at 9:27 AM on July 28, 2013 [1 favorite]


To overspecialize is to breed weakness.
posted by laconic skeuomorph at 9:32 AM on July 28, 2013 [5 favorites]


I have to provide links that there's more than one species of orange available?

no - but i'm looking for something that questions the veracity of the NYT reports - wouldn't it be more expensive to plant another variety of orange - and how do they stay in business as they wait for them to develop?

Or are you looking for a link that shows that the one in current use is optimized for shipping and shelf life and that handing over control of our food supply to corporate powers is worth it to save this one?

aren't multi-grove orange farms corporate powers? - isn't pepsi-cola the owner of tropicana?

seems to me we've already handed over control of our food supplies to them

i suppose you could make a case for local farmers and local distributors, but i don't think that's going to work very well in michigan, as far as oranges are concerned
posted by pyramid termite at 9:39 AM on July 28, 2013 [1 favorite]


News like this too soon after reading The Windup Girl gives me nightmares.
posted by Sequence at 9:41 AM on July 28, 2013 [5 favorites]


DU, as the article mentions, basically all commercial orange production is already limited to two types - not just two species but two genotypes, since orange trees are propagated by cloning. (Old-school cloning, the type that predates genetic engineering.)

I also don't get how this is "handing over control of our food supply to corporate powers." As pyramid termite pointed out, these are already corporate-owned orange groves. If smaller farmers are growing other orange cultivars that aren't vulnerable to this bacterium, then what these guys are doing doesn't matter one way or another. And if they are growing cultivars that are vulnerable, this should also help just through herd immunity - the bacterium can't spread as fast if we reduce the vulnerable population.
posted by en forme de poire at 9:45 AM on July 28, 2013 [4 favorites]



I have to provide links that there's more than one species of orange available?


All oranges are the same hybrid (species), Citrus x sinensis. However, the disease affects all citrus species, and infects other plants in the Rutaceae family. It's not a problem of just one orange variety that is optimized for shipping (most oranges can be shipped, they aren't like tomatoes), it's a problem of all citrus we regularly eat being very closely related to each other.
posted by oneirodynia at 9:47 AM on July 28, 2013 [4 favorites]


First, we need to modify a word so it rhymes with orange.
posted by hal9k at 9:48 AM on July 28, 2013 [5 favorites]


The genus of bacteria that's causing this (Candidatus Liberibacter) is scary as hell:
Named species include:[2]

Liberibacter africanus - Originating in Africa and a causal agent of huanglongbing, also known as citrus greening disease and vectored by the african citrus psyllid Trioza erytreae.[3]

Liberibacter americanus - A novel species from Brazil described in 2005 and associated with huanglongbing, also known as citrus greening disease and vectored by the Asian citrus psyllid Diaphorina citri.[4]

Liberibacter asiaticus - Originating in Asia and a causal agent of huanglongbing, also known as citrus greening disease and vectored by the Asian citrus psyllid Diaphorina citri.[5]

Liberibacter europaeus - A novel species described in 2010, found in pear trees where it seems to cause no symptoms and vectored by the psyllid, Cacopsylla pyri.[6]

Liberibacter psyllaurous - A novel species described in 2008 from solanaceous host plants potato and tomato and vectored by the potato tomato psyllid (TPP), Bactericera cockerelli.[7] Liberibacter psyllaurous plays a dual role as a plant pathogen and as an inherited bacterial endosymbiont. This symbiont modifies tomato defenses in favor of itself and its psyllid vector[8]

Liberibacter solanacearum[9] - A causal agent of zebra chip disease in potatoes and vectored by the potato tomato psyllid (TPP), Bactericera cockerelli.[10] There are four haplotypes described within this species, designated LsoA, LsoB (from solanaceous plants in North America) and LsoC, LsoD (from carrots in Europe)[11]

Liberibacter crescens[12] - isolated from papaya growing in Puerto Rico.
It's a member of the Rhizobiaceae family, which contains most of the nitrogen fixing bacteria found in the root nodules of legumes.

And legumes are notably absent from this list of food plants.

Tangy high-protein orange seeds, anyone?
posted by jamjam at 9:51 AM on July 28, 2013 [1 favorite]


hell, there aren't any words that rhyme with spinach, either
posted by pyramid termite at 9:52 AM on July 28, 2013


From the nature of many of these comments, it's clear that many of you, like me, can't get to the article, probably due to the NYTimes paywall. If that's the case, perform this Google News search and the first link takes you there.

Many of your concerns and questions will be answered, and we can level up from the standard OMG GMO script to OMG GMO citrus-agriculture-in-Florida back and forth, which is at least relevant to the topic.
posted by Llama-Lime at 9:56 AM on July 28, 2013 [1 favorite]


spinach
makes my skin itch
posted by fings at 9:57 AM on July 28, 2013 [4 favorites]


hal9k: First, we need to modify a word so it rhymes with orange.

Tom Lehrer already took care of that:

Eating an orange
While making love
Makes for bizarre enj-
oyment thereof.
posted by Kattullus at 10:02 AM on July 28, 2013 [16 favorites]


spinach
makes my skin itch


like he toes of...Dennis Kucinich?
posted by Greg_Ace at 10:04 AM on July 28, 2013 [3 favorites]


"Will my oranges taste like spinach?" - Actual Orange Farmer

Good grief. Imagine being the first guy to explain how vaccination and anti-venom work to these kinds of people. Genetically modified food? You're soaking in it, people. Might as well get used to it (again).

I did enjoy this line, though:
A salmon modified to grow faster was still awaiting F.D.A. approval.

I'm just picturing a salmon, suitcase all packed, eagerly asking "any word yet?"
posted by ShutterBun at 10:04 AM on July 28, 2013 [20 favorites]


So ... China doesn't have citrus greening, but we aren't willing to use Chinese techniques to make non-GMO orange juice? Instead we find an excuse to go on to some GMO.

It's interesting that this report shows that citrus greening was considered a bioterror weapon so scientists in the US were restricted from researching anything about it up until the last couple of years.

But it's really pathological that we don't take up solutions other than chemicals and GMO for problems like this.
posted by graymouser at 10:06 AM on July 28, 2013 [2 favorites]


I have to provide links that there's more than one species of orange available?

I sure would love it if the upshot of this orange blight was that satsumas got better press and wider distribution. Though my guess is that the reason satsumas aren't in every supermarket in the world is because they're less cost effective to ship for whatever reason. More finicky to grow? Don't travel well? Spoil more quickly?
posted by Sara C. at 10:12 AM on July 28, 2013


I meant to also say that [this is good]. Really really good article. It's not secret inside sources in the government, this is all real, verifiable information, that is easily checked, synthesized into a cohesive story that considers many angles. This is what journalism should be. Take for example, this:
If various polls were to be believed, a third to half of Americans would refuse to eat any transgenic crop. One study’s respondents would accept only certain types: two-thirds said they would eat a fruit modified with another plant gene, but few would accept one with DNA from an animal. Fewer still would knowingly eat produce that contained a gene from a virus.
I mean really, perceived risk as a function on difference or danger the donor organism? Makes nearly zero sense scientifically, yet in folk-logic, sure, why not? And why shouldn't a public, which knows nothing about GMO except to be wary, not think that way? This article contains many such insights that I wouldn't have thought of.

And think for a second that a reporter actually went out and did some research about public perception, and turned it into just a single paragraph of a story. Where are you going to get that amount of dedication in modern media? It's well worth the read. The NYTimes Science section is a paragon, the news I'm suspicious of, but the Science section reporters are the best in the business, beating out anything else in the world.
posted by Llama-Lime at 10:12 AM on July 28, 2013 [11 favorites]


"In the heat of last summer, Mr. Kress gardened more savagely than his wife had ever seen."

Is this the intro sentence to some Plants vs. Zombies fanfic?
posted by jclarkin at 10:13 AM on July 28, 2013 [3 favorites]


god damn it universe, Atwood wasn't supposed to be a prophet.
posted by dejah420 at 10:13 AM on July 28, 2013 [4 favorites]


Wait what? Wikipedia just informed me that satsumas are tangerines.

My tiny Louisiana mind just got blown. Why the fuck do we call them satsumas when the whole rest of America calls them tangerines?

I guess this explains why "satsumas" are not in every supermarket in America. They are. As "tangerines".
posted by Sara C. at 10:14 AM on July 28, 2013 [6 favorites]


hell, there aren't any words that rhyme with spinach, either

My childhood says "finnich", and I'm sticking with it.
posted by Thorzdad at 10:15 AM on July 28, 2013 [1 favorite]


Sara C, I think satsumas is also the term the British use. Mandarins and satsumas and tangerines, oh my. The Smithsonian's Design Decoded blog did a really interesting series on citrus which included the proliferation of new kinds of satsuma/mandarin/tangerine-style fruits (which peel easily and ripen at later and later times so they can hit the market after the navel oranges have gone), and other new technologies being used in citrus growing.
posted by LobsterMitten at 10:20 AM on July 28, 2013


I guess all I'm saying is we got plenty other tasty citrus fruits to nom if the monoculture oranges get busted.
posted by Sara C. at 10:23 AM on July 28, 2013


I thought Tommy Smothers had asserted the "door-hinge" rhyme decades ago. "Four-inch" also works, if you say it fast and mispronounce it a little.
posted by Cookiebastard at 10:32 AM on July 28, 2013 [2 favorites]




So ... China doesn't have citrus greening, but we aren't willing to use Chinese techniques to make non-GMO orange juice?

China did have citrus greening.
C. liberibacter, the bacterium that kills citrus trees by choking off their flow of nutrients [was] first detected when it destroyed citrus trees more than a century ago in China ...
It's doubtful China is free of citrus greening.
posted by de at 10:39 AM on July 28, 2013


since orange trees are propagated by cloning.

Makes me glad we're using spinach DNA and not amphibian DNA then. Last thing we need is a pack of feral-hatched orange trees roaming about, unaccounted for by the unsuspecting scientists. Florida's roughly 1/3rd theme park after all, and y'all remember what happened last time.
posted by radwolf76 at 10:47 AM on July 28, 2013 [4 favorites]


I would eat a GMO orange. I worry a lot more about pesticide use on my food. I'm glad it's not Monsanto cooking up the transgenic orange, though, because I seriously object to their business practices.
posted by jlh at 10:55 AM on July 28, 2013 [13 favorites]


These are genetic engineers we're talking about, who do you think created the disease?

I believe the ultimate genetic engineer created this disease - that would be evolution.

But given how expensive developing a GM orange would be, I can't imagine the orange juice lobby really wants to do this. I mean, they want to continue to exist, so they will do this to combat the disease, but right now they are burning crops to avoid that and that's not great for your profit margins.
posted by maryr at 11:03 AM on July 28, 2013 [2 favorites]


hell, there aren't any words that rhyme with spinach, either

Eat your spinach
Grown in Greenwich.
posted by axiom at 11:06 AM on July 28, 2013 [6 favorites]


Sara C. I guess all I'm saying is we got plenty other tasty citrus fruits to nom if the monoculture oranges get busted.

Nope. From the USDA's "Hungry Pests" page on citrus greening: Citrus greening disease affects a variety of citrus bearing trees. Known susceptible plants include orange, lemon, lime, grapefruit, kumquat and tangerine trees.

and

Citrus greening disease has the potential to destroy and eliminate the citrus industry in the United States. In areas known to be affected by citrus greening disease, citrus crops have been seriously threatened or even completely destroyed.
posted by jocelmeow at 11:09 AM on July 28, 2013 [3 favorites]


de: China has fought citrus greening without using GMO techniques, which was my point. So why exactly aren't we following what they did instead of trying bizarre GMO techniques? (Hint: It has to do with the question cui bono?)
posted by graymouser at 11:15 AM on July 28, 2013 [1 favorite]


"Your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should", says Ian Malcolm.

And then Kress is eaten by one of his mutant oranges.
posted by mr_crash_davis at 11:19 AM on July 28, 2013 [1 favorite]


de: China has fought citrus greening without using GMO techniques, which was my point. So why exactly aren't we following what they did instead of trying bizarre GMO techniques? (Hint: It has to do with the question cui bono?)
How did China fight citrus greening? Was it by just stopping most citrus growth in those areas? If you look at the map in the article, a good chunk of China still seems to be infected.

If you read the article, you'll see that there are plenty of farmers that would love to fight the disease without GMO. Who benefits if they go GMO? The farmers seem to think that it will damage the entire industry.

And who else benefits if they go GMO? Specifically?
posted by Llama-Lime at 11:22 AM on July 28, 2013 [1 favorite]


hal9k: "First, we need to modify a word so it rhymes with orange."

When I was a child I looked up "orange" in a rhyming dictionary. To this fucking day I have problems pronouncing "melange" correctly.
posted by stet at 11:33 AM on July 28, 2013 [1 favorite]


My tiny Louisiana mind just got blown. Why the fuck do we call them satsumas when the whole rest of America calls them tangerines?

This is probably not the right time for me to mention clementines then.
posted by FelliniBlank at 11:38 AM on July 28, 2013 [4 favorites]


i don't understand why we don't just build nano-battlebots to punch the bacteria in their tiny faces.
posted by George_Spiggott at 11:39 AM on July 28, 2013 [13 favorites]


Australia can supply the world's uranium and OJ.

Is this how far Australian cocktail culture has fallen?
posted by ActingTheGoat at 11:42 AM on July 28, 2013 [6 favorites]


First, we need to modify a word so it rhymes with orange.

Hmm, I just realized that this issue is going to be hell on anti-GMO chant organizers.
posted by Tell Me No Lies at 11:43 AM on July 28, 2013 [14 favorites]


trying bizarre GMO techniques?

One man's "bizarre GMO techniques" is another man's "um, this is how science works."
posted by ShutterBun at 11:43 AM on July 28, 2013 [9 favorites]


I meant to also say that [this is good]. Really really good article. It's not secret inside sources in the government, this is all real, verifiable information, that is easily checked, synthesized into a cohesive story that considers many angles. This is what journalism should be.

I agree. If I wanted to introduce someone to the economic and political GMO situation in the U.S. this is where I'd start them.

NYT needs a tip box.
posted by Tell Me No Lies at 11:47 AM on July 28, 2013 [2 favorites]


"two-thirds said they would eat a fruit modified with another plant gene, but few would accept one with DNA from an animal." posted by Llama-Lime

OK, you were quoting the article, but surely this merits an eponysterical, no?
posted by ShutterBun at 11:48 AM on July 28, 2013 [11 favorites]


srboisvert: "
Don't be silly pyramid termite. These are genetic engineers we're talking about, who do you think created the disease?


Charles Darwin! Quick get the orange hating bastard off the £10 note!
"

If it wasn't for Darwin and his theories of Evolution, evil Hitler wouldn't have been involve with theories of eugenics and, and maybe we'd still have Juice.
posted by symbioid at 11:52 AM on July 28, 2013


How did China fight citrus greening?

As far as I can tell, the main things are to plant mangos among the citrus, use topical insecticides and introduce natural predators of the psyllid. It's mostly about psyllid management but farming that is dependent on monoculture and chemical insecticides doesn't seem willing to do this.
posted by graymouser at 12:01 PM on July 28, 2013 [2 favorites]


As far as I can tell, the main things are to plant mangos among the citrus, use topical insecticides and introduce natural predators of the psyllid.

So I don't know the specifics of this - i.e., what pesticides and predators are being used here - and that can make quite a big difference. But one of the main things this project is trying to accomplish is actually to make the oranges more robust without having to drench them in insecticide or other pesticides. And as far as unintended ecological consequences, introducing a natural predator does not have a great track record - plus IMO, it is a way bigger perturbation to the ecosystem than engineering in a single gene for bacterial resistance.
posted by en forme de poire at 12:21 PM on July 28, 2013 [1 favorite]


It is a way bigger perturbation to the ecosystem than engineering in a single gene for bacterial resistance.

Just quoting you, but I saw forms of this reasoning throughout the nytimes comments as well. The problem I have with it is that it is not a valid comparison between two well-described costs, but rather an attempted comparison between known costs (we know, i.e. have real evidence of the costs of the various old solutions for caring for our crops) and unknown costs (we have no such actual evidence of or proof about the environmental costs of transgenics). But the known and the unknown are not comparable; it could be argued that is a kind of category error. People conveniently forget that absence of proof is not proof of absence, and then conclude that technocratic solutions like GMO is the way to go. It is poor thinking and poor problem solving, from the standpoint of any competent scientist or engineer.
posted by polymodus at 12:32 PM on July 28, 2013 [3 favorites]


Huh. Where I grew up oranges are all green and yellow all the time. You saying it's a disease now? For reals? We still eat them.

Not understanding the problem.
posted by glasseyes at 12:32 PM on July 28, 2013


On preview, looks like we won't be able to afford expensive gene-splicing tech in Nigeria so we'll be alright then.

/Luddite proud and comfortable.

I mean honestly, this looks like a cosmetic problem to me. So oranges are green, not orange? But taste just as they ever did? And?
posted by glasseyes at 12:34 PM on July 28, 2013


It makes the fruit salty and bitter and eventually kills the trees. See here.
posted by LobsterMitten at 12:52 PM on July 28, 2013 [3 favorites]


So why exactly aren't we following what they did instead of trying bizarre GMO techniques?

well, from the reuters article, it seems that they're ---

1 - burning infected areas to the ground - i'm sure that works, but it's not going to be good for business

2 - paying 60 to 70 technicians what 3 or 4 would cost in our country

3 - handing out a shitload of flyswatters to peasants - that's not going to work in a country where, close to my town, asparagus farmers are plowing under their crops because they can't get enough workers to harvest them
posted by pyramid termite at 1:05 PM on July 28, 2013 [1 favorite]


Polymodus: but we do in fact have information about genetically engineered crops because there are several in existence. Economic and legal issues aside, I am not aware of any ecological disasters caused by GM crops, certainly nothing on the scale of the problems that have been caused by the introduction of a non native predator.

Besides that, your position here is so conservative that it would seem to preclude most scientific innovation, particularly in the life sciences (vaccines, antibiotics, pesticide use, etc).
posted by en forme de poire at 1:11 PM on July 28, 2013 [1 favorite]


This is probably not the right time for me to mention clementines then.

Yeah, but clementines are a whole different thing, right?

Wait, are clementines also tangerines?

*dies*
posted by Sara C. at 1:50 PM on July 28, 2013 [1 favorite]


Hooray for monoculture!!!
posted by hwestiii at 1:58 PM on July 28, 2013


I mean honestly, this looks like a cosmetic problem to me. So oranges are green, not orange? But taste just as they ever did? And?

Sorry if you're joking, but if not, read the article.

Citrus greening is a disease that causes oranges to grow small and misshapen, with a bitter taste, then kills the tree it infects within a few years.

Aside: I grew up in the town in the article, Clewiston FL.
posted by the jam at 2:15 PM on July 28, 2013 [1 favorite]


Also, everyone saying "told you so" re: monocultures, this is a disease that affects nearly all citrus fruits, from grapefruits to lemons to oranges. This isn't about monocultures.
posted by the jam at 2:19 PM on July 28, 2013 [4 favorites]


greymouser: China has fought citrus greening without using GMO techniques, which was my point. So why exactly aren't we following what they did instead of trying bizarre GMO techniques?

I have been following this topic a little bit from time to time because I used to work in the produce biz (stone fruit rather than citrus, though). For folks who are interested, it might help, in looking for information, to know that the original name for this is huanglongbing.

From an article titled Citrus Huanglongbing: Understanding the Vector-Pathogen Interaction for Disease Management out of the University of Florida Citrus Research and Education Center:
Currently, no studies have been conducted proving that managing psyllid populations will indeed provide a benefit in terms of reducing the spread of citrus greening disease. Researchers from countries such as China and South Africa report anecdotal evidence for the need to control psyllids to minimize disease spread and maintain viable citrus production (10,27). However, in each of these growing regions there are differences in climate, cultural practices, and even strains of the pathogen or vector species which makes direct comparison of results difficult.
There are examples where demonstrated low vector populations have limited the spread of the pathogen. In China, for example, greening disease has severely limited citrus production in the lowland areas where D. citri is relatively abundant. In contrast, in the highland areas of China greening disease is not a problem (27). In these areas of higher altitude, D. citri survival is low and thus spread of Ca. L. asiaticus is also low. However, in this particular situation, the cold weather also affects citrus, thus limiting production to mandarin varieties which are better suited for the colder environment.
The situation in Florida is much different as the climate and current production practices are ideal for buildup of large psyllid populations. It is thus impractical to attempt to eliminate psyllids to virtually undetectable levels as this would require an inordinate and unsustainable amount of insecticide applications. A more realistic and sustainable approach to psyllid management would be to target psyllids during the periods when pathogen spread is more likely to occur. This will require knowledge of the seasonal trends for higher percentages of psyllids carrying and transmitting the citrus greening pathogen, if such differences do exist. In addition information is needed regarding when those psyllids are likely moving and infecting healthy trees.
From UC Davis' Integrated Pest Management page on huanglongbing (IPM, in brief, is a strategy that prioritizes several alternative approaches before traditional pesticide use):
Biological Control
Several predators and parasites feed on different life stages of the psyllid. The nymphs are killed by tiny parasitic wasps and various predators including lady beetles and their alligator-shaped larvae, syrphid fly larvae, lacewing larvae, and minute pirate bugs. Some spiders, birds, and other general predators also feed on adult psyllids.

Because the Asian citrus psyllid recently arrived in California, it doesn’t yet have a full complement of natural enemies to help control its populations. Biological control will improve as the psyllid’s natural enemies increase, but this won’t eliminate the pest or prevent it from transmitting the disease.

Chemical control is currently the most effective method to control the Asian citrus psyllid, especially if the purpose of control is to prevent spread of the psyllid to new areas of California. In other areas of the world where Huanglongbing is present, natural enemies aren’t effective enough against the psyllid to keep the disease from spreading, and insecticide treatments are needed to protect citrus trees.
When the IPM folks say chemical control is the most effective method, biological methods are pretty much hosed.

The NYT article doesn't mention it, but introducing natural predators has been tried in Florida, without success (more details in this earlier release):
ACP is attacked in Asia by two tiny parasitoid wasp species, Tamarixia radiata and Diaphorencyrtus aligarhensis. T. radiata is regarded as the more effective. Classical biological control projects, therefore, have been conducted to establish T. radiata in a number of countries invaded by ACP including Mauritius, Réunion Island, Taiwan, Guadeloupe, and the United States (Florida). T. radiata has been inadvertently introduced into Puerto Rico, Venezuela, Brazil, Costa Rica and other areas in the New World. ACP and T. radiata were probably unknowingly introduced into these areas at the same time through the movement of infested host plants. Dramatic success in reducing populations of ACP was achieved following establishment of T. radiata in Réunion Island, with ACP reductions large enough to mitigate HLB. Good levels of biological control have been reported in Guadeloupe and Puerto Rico (although it has not been reported from these areas if biological control of ACP has been enough to mitigate HLB). In contrast to these cases where biological control has significantly reduced ACP populations, only mediocre biological control of ACP has been achieved by T. radiata in Florida citrus.
Having spent a portion of my career working with farmers, believe me, if there is a cheaper, easier, already-established effective way to do something - and almost anything would be cheaper and easier than the described hail-mary research approach - they tend to take it.
posted by jocelmeow at 2:24 PM on July 28, 2013 [8 favorites]


I'm impressed that genetic manipulation (specifically transformation) of citrus trees doesn't seem to have been a limiting technical issue.
posted by maryr at 3:13 PM on July 28, 2013 [2 favorites]


Also, everyone saying "told you so" re: monocultures, this is a disease that affects nearly all citrus fruits, from grapefruits to lemons to oranges. This isn't about monocultures.

The arrival of the disease may not be about monocultures, but the effects of it certainly are. They are unable to find a citrus tree *of the current cultivated breeds* that is immune. That leaves a lot of room, in fact nearly all the room of the world as the number of cultivated breeds is tiny.

The problem is that a consumer knows what an orange is. An orange has a very specific taste and consistency, it peels a certain way, and the smell after the garbage disposal gets done with the rinds is always the same. The large growers need that specific orange.

Were the consumer definition of orange much wider -- in the best case all of the many varieties of the species -- this would not be the issue that it is.
posted by Tell Me No Lies at 4:04 PM on July 28, 2013 [1 favorite]


This does not appear to be true. The Wikipedia page for huanglongbing states that despite a global search, no naturally occurring orange species was found to be resistant.
posted by en forme de poire at 4:21 PM on July 28, 2013 [2 favorites]


Interesting. I wish it had a cite, I can't find anything to back it up.
posted by Tell Me No Lies at 6:51 PM on July 28, 2013


It would be interesting if "real" oranges were to eventually reach the heirloom status of apples.

Better give everyone you know one of these for Christmas. They could be valuable someday.

hell, there aren't any words that rhyme with spinach, either

My childhood says "finnich", and I'm sticking with it.


Yeah, dad used to rhyme it all the time:

You finnich
yer spinnich
Or you'll damn well
sit there.
posted by BlueHorse at 7:13 PM on July 28, 2013 [2 favorites]


Polymodus: but we do in fact have information about genetically engineered crops because there are several in existence. Economic and legal issues aside, I am not aware of any ecological disasters caused by GM crops, certainly nothing on the scale of the problems that have been caused by the introduction of a non native predator.

Besides that, your position here is so conservative that it would seem to preclude most scientific innovation, particularly in the life sciences (vaccines, antibiotics, pesticide use, etc).


Yes, there exists "field data" on the impact of these technologies. But when one considers the scope of the problem, it's not hard to come up with reasons why such extant information is, nevertheless, a narrowly focused, limited sample size. The rational approach is to recognize that the actual burden of proof is indeed nontrivial, and then acknowledge and work with the concerns. Apparently that is too hard for some people, such as a few nytimes commenters, and in particular the most voluble ones that rely on the illogical argument that I mentioned previously. It more valuable to have a deeper understanding of the actual problem—i.e., weighing the risks and tradeoffs of bioengineering technology, as well as clarifying potential versus actual future impact on the global ecosystem, than, for instance, taking either pro-/anti-GMO sides based on biased hunches and preferences.

It's interesting that you mention scientific innovation as a social priority, because scientific ethics go hand in hand with progress and discovery. Indeed, take for example pesticides: What history truly tells us—for example with the case of DDT—is that there are no easy answers. That is a point that is too easily forgotten.
posted by polymodus at 7:25 PM on July 28, 2013


The thing that bugs me about GMO is that it often seems to be messing with organisms that nature already did a pretty good job of designing, and often for some dumb motive like profit. I understand this situation is a bit different, but I can't help but think that if we hadn't just done things more sensibly to begin with we wouldn't be facing so many eco-crises like this one. Like, maybe if we weren't so agro-greedy we wouldn't need to keep modding the planet to get it back to being almost as good as it was in the first place?

Also, if we irrevocably gum up a species DNA (and therefore its "fruit") I'm going to be pissed. I mean, if you really want to know how priceless a tomato is just wait until you can't get a decent one. (Which is pretty much now, at least in a supermarket.)
posted by nowhere man at 8:32 PM on July 28, 2013


Even if a GMO solution is the way to go, what exactly is it? jocelmeow's quote above from the University of FL says: "This will require knowledge of the seasonal trends for higher percentages of psyllids carrying and transmitting the citrus greening pathogen, if such differences do exist. In addition information is needed regarding when those psyllids are likely moving and infecting healthy trees. "

That sounds like more basic science is needed, as we head into an era when legislators regularly demand proof of value before handing out research funding. I think we're too easily swayed by promises of GM technology just because its promoters make it sound like a cheap and easy way to avoid understanding the complexities of the disease.
posted by sneebler at 8:34 PM on July 28, 2013


How can we be sure that employing GMO methods is not just a repeat of what was done with antibiotics vs. bacteria? I think it's important to remember that these "enemies" of ours fight back by evolving ways to circumvent our solutions.

We're already seeing plants that are becoming more and more resistant to glyphosate, right?

I obviously don't have the answer, and I'm not suggesting we simply let all citrus crops go extinct, but it seems to me that humanity's fixation on short term solutions keeps biting us in the ass.
posted by InsertNiftyNameHere at 8:48 PM on July 28, 2013 [1 favorite]


As mentioned in the article, they tried to give you a better tomato through GMO. It wasn't cost efficient and the company that made them went out of business. The invisible hand of the supermarket?
posted by maryr at 8:49 PM on July 28, 2013 [1 favorite]


(Also, I think Bt toxin would be a much better comparison here than glyphosate resistance.)
posted by maryr at 8:56 PM on July 28, 2013 [1 favorite]


maryr: "(Also, I think Bt toxin would be a much better comparison here than glyphosate resistance.)"

I heartily agree, and many thanks to you for mentioning it. I had never even heard mention of Bt toxin. From the tiny bit of reading I've just done, this stuff looks enormously scary!
posted by InsertNiftyNameHere at 9:03 PM on July 28, 2013


...Quite the opposite in my opinion. No proven effect on anything but insects and the study most commonly cited for its effects on Monarchs had serious methodology flaws. But I'm trying not to threadsit so I'll go to bed now.
posted by maryr at 9:10 PM on July 28, 2013 [2 favorites]


In the past several years, out of public view, he has considered DNA donors from all over the tree of life, including two vegetables, a virus and, briefly, a pig. A synthetic gene, manufactured in the laboratory, also emerged as a contender.

Unfortunately, nothing rhizomes with oranges.
posted by Uther Bentrazor at 9:23 PM on July 28, 2013 [8 favorites]


The thing that bugs me about GMO is that it often seems to be messing with organisms that nature already did a pretty good job of designing, and often for some dumb motive like profit.

Nature? Oranges? The article seems to make it clear that every orange you've ever seen has been a product of man's involvement in one way or another.

And since when is "profit" not a good reason to adjust the technology of agriculture? You'd prefer they all went broke, abandoned oranges, or started charging Soylent Green era prices for them?
posted by ShutterBun at 10:11 PM on July 28, 2013 [1 favorite]


If you'd rather all orange growing be done by nonprofits, that's a totally fine and non-capitalist way to be. But the fact remains that nobody is going to be growing oranges at all if citrus greening wipes them out.
posted by the jam at 11:10 PM on July 28, 2013 [1 favorite]


far as i can tell, it is a big yawn form OJ futures perspective
http://finviz.com/futures_charts.ashx?t=JO&p=w1
posted by dougiedd at 11:12 PM on July 28, 2013


My intuition tells me a significant portion of the folks clamoring to the cause of damning the spinach DNA altered orange are in fact enjoying the most potent laboratory field tested marijuana money can buy.

For my money, I'd prefer a broccoli or brussell sprout strain.
posted by vozworth at 11:22 PM on July 28, 2013


There are very good reasons to be concerned about the way GM is being used in agribusiness. That doesn't mean GM is innately bad. The horrors of Monsantoesque Frankenfoods include things like expressing toxins and antibiotics -- which for many reasons should be cause for concern when introduced into the environment, let alone the food chain -- and genetic cross-contamination, as well as basically shitty business practices.

But if the cure here is a simple protein that we can eat safely because we do all the time in spinach but which this particular bacterium cannot abide, and if genetic cross contamination is a positive boon -- i.e. other citrus varieties pick it up -- then it's hard to see the down side.

Obviously some very thoughtful testing and analysis needs to take place here. But this doesn't freak me out the way most GM does; most of the usual red flags are, so far, absent.
posted by George_Spiggott at 11:44 PM on July 28, 2013 [4 favorites]


I'm not even opposed to GM food on principle, but this article has so much fucking subtle hippie-punching and attempts to bring Monstanto's ugly business practices and pesticide-arms-race brand of GM under a "save the oranges" rug.
And when the E.P.A. informed him in June 2012 that it would need to see test results for how large quantities of spinach protein affected honeybees and mice, he gladly wrote out the $300,000 check to have the protein made.

It was the largest single expense yet in a project that had so far cost more than $5 million. If these tests raised no red flags, he would need to test the protein as it appears in the pollen of transgenic orange blossoms. Then the agency would want to test the juice.

“Seems excessive,” Dr. Mirkov said.
Gee a rich businessman is spending a lot of money to pay for tests to ensure his scientifically-engineered oranges don't kill mammals or our (totally not in any danger) pollinators in-vitro or in-vivo. Let me get my tiniest violin out for this bureaucratic travesty.

As well as the anti-labeling bullshit, with the article blaming it on Big Organic and saying
He did not aim to hide anything from consumers, but he would want them to understand how and why his oranges were genetically engineered. What bothered him was that a label seemed to lump all G.M.O.’s into one stigmatized category.
Dude go for it - tell us exactly what genes you spliced in, what proteins they code for, and why. I'm sure most of the dirty hippies would pretty pretty happy with an excess of detail slapped on the package. Between the lines it sounds more like a slight-of-hand where we're against this terrible "lumping" and then Tropicana is going to wind up with a "Citrus Greening Immune" smiley-face logo on it.

It was a fascinating but infuriatingly one-sided pro-corporate article. Oh, right, nytimes.com
posted by crayz at 11:50 PM on July 28, 2013 [3 favorites]


maryr: "...Quite the opposite in my opinion. No proven effect on anything but insects and the study most commonly cited for its effects on Monarchs had serious methodology flaws. But I'm trying not to threadsit so I'll go to bed now."

Congratulations on setting a trap that I was gullible (and uninformed) enough to not see. You've succeeded marvelously at deceiving a single layman.

So, we'll play it your way. Bt toxin is harmless. How does that change the fact that GMO modifications will eventually be defeated by natural evolution? How long (I should say short) has it been since crops GMO modified to tolerate glyphosate (and secondary plants) have started to show signs of resistance?
posted by InsertNiftyNameHere at 11:59 PM on July 28, 2013


Also I love the article's constant refrain that we know what these genes "do", like we're just adding some rum to our cola, "It’s not where a gene comes from that matters, It’s what it does.", contrasted with the need to test a bunch of different genes from all over the tree of life and
When some of the scientist’s promising trees got sick in their first trial, Mr. Kress agreed that he should try to improve on his results in a new generation of trees, by adjusting the gene’s placement.
Oh now the gene placement matters, life pouring the rum in after the coke? Well how many different places could there be? Fuck. It's almost as if we can't predict this stuff's effect as well as we like to claim when we're talking to the safety committee!
posted by crayz at 12:23 AM on July 29, 2013 [1 favorite]


Oh now the gene placement matters
Gene placement matters in at least two ways: 1) hooking the gene into the proper regulation program and 2) disrupting and deactivating other genes or functional genomic elements.

As you point out, the rum and coke analogy is not particularly useful here, there's a lot more going on. The desired effect is to add some amount of protein the cells of the citrus tree, which could supposedly be the rum in your analogy. But you don't add the rum, you add the rum-making instructions. That's essentially what a gene is, instructions for a protein.

The citrus genome keeps its instructions in 9 volumes, each a linear chain, jut as text in a book is a linear chain.

Now, it's not like every cell is just making all the proteins all the time, it's far more controlled. Each type of cell, leaf, blossom, whatever, has all the same instructions, but opens up different parts of the book, by maintaining sections of the DNA as euchromatin (open) or heterochromatin (closed). The DNA is maintained in the state by various type of proteins, some of which, the histones, are the most identical proteins we know about across all the eukaryotes. Which means that small changes in the histones, unlike most proteins, results in them functioning worse enough to impair the organism. And the boundaries of what is open or closed are maintained by other proteins. As a plant grows from a seed, various parts are opened and closed (by yet different proteins) to differentiated cells into the various specialized cells an adult plant needs in order to be a plant. What parts that are opened or closed are at least in part determined by sequences in the DNA that are recognized by certain proteins or groups of proteins.

In addition to open or closed sections of DNA, there's the question of how much protein should be made in a cell, and at what times (continuously, in response to a particular hormone, in response to a stress, etc.). This part of the gene regulatory program is run by yet another set of proteins that bind to promoters in front of genes. If a gene is located in a section of euchromatin, and the right combination of proteins are expressed that bind to that genes promoter, the gene's instructions for a protein can be copied out, and sent off of to the protein factory. (There's also a whole lot of regulation going on during this stage, but I'm trying to keep this cartoon simple.)

So to get back to 1) up there, placement matters a great deal because it will determine if a gene actually makes the protein, and if it makes it in the right type of cells, ie the new gene must be in a section of DNA that is in the euchromatin state in the right type of adult cells.

Second, the gene must not be placed somewhere that interrupts another one of those sections of DNA that get recognized by other proteins, and it must not be placed in the middle of another gene, because disrupting that other gene's instructions will effectively disable it. On large genomes, this is somewhat easier, as there's a lot more filler DNA that can be modified without effect. But the citrus genome is only about 400 million bases long, which means that it has 90% less disruptable DNA then humans, for example. So getting it wrong will mean that the plant will probably grow less effectively at some stages or situations, or not at all. And like all biology and even life itself, the end result is achieved through lots of trial and error. Randomly disrupting the genome is a frequent biology investigative tool, and pre-GMO such random bombardment was used in agriculture and horticulture.

So yeah, placement is pretty important.
posted by Llama-Lime at 3:26 AM on July 29, 2013 [3 favorites]


Nature? Oranges? The article seems to make it clear that every orange you've ever seen has been a product of man's involvement in one way or another.

There's a big difference between hybridization a la Mendel and genetic manipulation.

And since when is "profit" not a good reason to adjust the technology of agriculture? You'd prefer they all went broke, abandoned oranges, or started charging Soylent Green era prices for them?

I didn't say that. However I will say that when it comes to things like education, health care and yes food there are a lot of good reasons not to rig the system so it's all about turning a buck.

I guess some folks really love their unfettered capitalism and their GMO foods. You can have 'em. Hippie peace love and out.
posted by nowhere man at 6:01 AM on July 29, 2013 [1 favorite]


I guess some folks really love their unfettered capitalism and their GMO foods.

I am fine with GMO foods (within reason) and not fine with unfettered capitalism. There is absolutely no reason that these two things have to go together.

Yes, there exists "field data" on the impact of these technologies. But when one considers the scope of the problem, it's not hard to come up with reasons why such extant information is, nevertheless, a narrowly focused, limited sample size.

I agree, but IMO this is a quantitative, not a qualitative difference from previous technologies.
posted by en forme de poire at 8:48 AM on July 29, 2013 [1 favorite]


Also, I think Bt toxin would be a much better comparison here than glyphosate resistance

Both cases show the poverty of current genetic engineering, though.

I mean, in principle, I'm all for it. I actually want the full-on, no-shit frankenfood. I want bacon trees, and watermelons that grow pre-vodka-ed, and beefsteak tomatoes that mean it, etc etc. Cows that give chocolate milk. At the boring level, corn that fixes its own nitrogen.

But what do we actually get? Crops that are marginally cheaper to produce because the farmer can just say "Fuck it" and spray the whole fucking field with roundup. Plants that make their own poison.* Whoopee. This shit, I can't get excited for.

*I have to admit this is still preferable to spraying crops with uncontrolled self-replicating self-modifying nanotechnological poison factories, aka spraying Bt directly.
posted by ROU_Xenophobe at 8:52 AM on July 29, 2013 [2 favorites]


It's weird to me that the word "patent" appears only once in this article, in the context of a negative comparison to Monsanto:
To Mr. Kress in early 2011, any comparison to Monsanto — whose large blocks of patents he had to work around, and whose thousands of employees worldwide dwarfed the 750 he employed in Florida at peak harvest times — seemed far-fetched. If it was successful, Southern Gardens would hope to recoup its investment by charging a royalty for its trees. But its business strategy was aimed at saving the orange crop, whose total acreage was a tiny fraction of the crops the major biotechnology companies had pursued.
What are we to infer from this? That his is a kindly mom-and-pop business with only the good of the orange crop at heart? If the comparison to Monsanto is unfair or invalid, how so? What is his business plan with respect to the work product of all this? What will he do differently?
posted by George_Spiggott at 9:15 AM on July 29, 2013 [1 favorite]


George_Spiggott, I think those are fair questions. I think it really depends on the patent and how broad it is. I think gene patents are mostly bullshit but within the (messed up) IP framework of the USA I think it's not unreasonable to allow a patent for a particular genetically-engineered tree. However, since commercial orange trees are 1) a much smaller market and 2) mostly grown by grafting (i.e., deliberate cloning), I think it's unlikely that there would be a "GM grain blew into my field" case analogous to Monsanto's.
posted by en forme de poire at 9:32 AM on July 29, 2013


Err well the entire point of the article seems to be that without the genetic modification all the orange trees are doomed. And once you've got a single tree you can replicate them by grafting - so is Kress planning a Monsanto-style ban on propagating your own trees without paying him royalties, or can I just buy one and then plant a farm full, or sell my homegrown trees on to others?

A world where no one owns or has distribution rights on the "intellectual property" that underlies their own plants is maybe something worthy of more debate than deigned by the NYT.
posted by crayz at 10:07 AM on July 29, 2013


I was curious what other research was being done besides the project in the linked article, and the Agricultural Research Service is throwing a lot at the problem. Here is one of the non-GMO projects underway:

Scientists at Ft. Pierce have evidence that suggests that guava, interplanted with citrus, prevents the spread of greening. Scientists in Japan and Viet Nam discovered that HLB did not occur in citrus groves when intercropped with guava, while control plots had over 30 percent infection. The mechanism may be volatile compounds produced by guava which disrupt the ability of the psyllid vector of HLB to locate its citrus host. Studies are underway in field plots to validate these preliminary findings and to identify the potential volatiles.

(Confusing insects rather than killing them with pesticides is something done as part of IPM. One way it's done is you can lace the orchard with the bugs' particular pheromones when they are maturing so they can't find each other to mate.)

Here is a very interesting set of slides (PDF) with photos of orchards in Vietnam that informs us that Southern Gardens has contributed a number of test plots to the guava research effort.

That project seems to have been running for five years. A 2012 update records some success:
Guava vs no guava nurseries: Two nursery sites, a guava protected citrus nursery versus an unprotected nursery, have were established with disease free, PCR-negative citrus trees (2 sweet orange and 1 grapefruit cultivars) in June 2009 and were located in the protected and unprotected plots. The guava trees were grown to appropriate size as indicated in Vietnam prior to outplanintg. To date HLB appears to be progressing more slowly in nursery plots interplanted with guava that non interplanted plots.
The previous year's update records some challenges:
This project was designed to examine the potential disease control of citrus huanglongbing (HLB) by interplanting citrus with guava. In Vietnam guava has been shown to be an effective deterrent to HLB, slowing the disease and keeping plantings alive for up to 15 years that normally succumb in 2-3 years. For all plots and experiments, Guava trees, (Vietnamese white cultivar) were propagated and grown to appropriate size requiring ~1 year. Both nursery and field citrus trees are assayed for HLB every 60 days, and have been assayed multiple times. Psyllid populations are monitored continuously every 2 weeks to document repulsion of the vector. For Guava vs. no guava nurseries: Two nursery sites, a guava protected citrus nursery versus an unprotected nursery, have were established with disease free, polymerase chain reaction (PCR)-negative citrus trees in June 2009 and were located in the protected and unprotected plots. The guava trees were grown to appropriate size as indicated in Vietnam prior to outplanting. To date HLB appears to be progressing slowler in nursery plots interplanted with guava than in non interplanted plots. The freezes discussed below did not adversely affect these nursery plots. For Citrus/guava interplantings: 2 commercial plantings with multiple replications were established but due to freezes and property sales these plantings are no longer viable. A third trial planting was established at the USHRL Picos Farm in Fort Pierce. The Picos plot was interplanted with citrus in August 2009. Severe frosts during 2008/2009 and again during 2009/2010 winters affected the U.S. Horticulture Research Lab plots and caused a delay in the experiment. A final hard freeze during the 2010/2011 season killed most of the guava trees. Data analysis to date indicates no differences were observed among treatments, i.e., guava interplanted vs. non-interplanted plots prior to the final demise of the plots. Our interpretation is that Florida is actually a subtropical environment, prone to intermittent freezes and cool or cold temperatures; whereas, Vietnam and Indonesia, where the guava effect seems to work, are truly tropical without such broad temperature swings. It is the new flush of guava which appears to be the best at producing Asian citrus psyllid (ACP) repellent volatiles. Cool or freezing temperatures inhibits volatile production and thus the citrus crop is left unprotected from ACP. While guava not be a viable deterrent as an intercrop, it still may be possible to identify individual volatiles from guava that might be useful under field applications as chemical applications. We are now switching direction slightly to investigate other more temperate Myrtaceous plant species that are more cold tolerant and might be useful as intercrops.

posted by jocelmeow at 10:37 AM on July 29, 2013 [3 favorites]


There's a big difference between hybridization a la Mendel and genetic manipulation.

I'm actually kind of curious how you see this difference. Is it just the range of cross breeding that becomes possible? The supposed accuracy?

At their heart they're both about finding genes that provide desirable attributes and mixing them into existing species. What about the difference bugs you?

(I feel the need to note that this is an exploratory question on my part, not a lead up to a gotcha or anything)
posted by Tell Me No Lies at 10:39 AM on July 29, 2013


Congratulations on setting a trap that I was gullible (and uninformed) enough to not see. You've succeeded marvelously at deceiving a single layman.

I sincerely was not trying to lay a trap. You knew enough to name glyphosate (and not call it Roundup), so I thought you'd be familiar with Bt toxin as well. It is widely used in soybeans, corn, and cotton and has been controversial in the past, i.e. the flawed butterfly study I mentioned above. I was not trying one up you in any way. Herbicide resistance has major flaws. I think that Bt toxin is both a better comparison to the spinach gene (targets one species/family, should be mostly contained within the plant) and a better idea.

But what do we actually get? ... Plants that make their own poison.

Plant have been making their own poison for millions of years, e.g. foxglove, hemlock, poison ivy (it's in the name!). Furthermore, compounds that are poisonous to us are not necessarily poisonous to other species - caffeine, for example.

As for resistance...I mean, I don't quite know how to argue that. Yes, life finds a way. Almost every method of disease resistance we can find will probably be overcome at some point. I don't think the solution is never using those methods in the first place. Antibiotic resistance is a real growing problem and we should regulate their use better (for example, in farm animals) but we don't stop prescribing tetracycline altogether because of it.

Glyphosate resistance arises in part because it's in response to an herbicide we spray all the fuck all over. So you have pressure from random mutations in nature to develop resistance. Only the plants that survive pass on their genes so once that mutation develops, the heritability is going to go pretty high pretty fast. On top of that, corn and weeds are not unrelated species. They're both monocots. So you have genetic drift as well - that's a whole other argument about GM crops though. Pollen is a bitch.

As for Bt toxin - first of all, the likelihood of genetic drift between corn and insects is pretty minimal. Second, and I don't believe this is true of Roundup ready crops, there are laws about how much Bt+ corn you can grow in a region - you have to grow wild type corn as well, I think to make sure we don't wipe out corn borers and fuck up the ecosystem, but I'm not on the regulation side of things. On the science side, yes, it's been shown that (lab) populations can evolve to withstand Bt toxin. There aren't many cases in the wild and improved expression has minimized that. Additionally, the use of Bt+ crops have led to a diminished use of pesticides in crops all over the world. It still seems better to me to use fewer pesticides, at least for a while, and reserve those pesticides that do work as a last resort. If bugs can evolve past Bt toxin, let's go in to the lab and evolve Bt toxin right back at them (that's what the improved expression did).
posted by maryr at 12:38 PM on July 29, 2013 [2 favorites]


crayz: And once you've got a single tree you can replicate them by grafting - so is Kress planning a Monsanto-style ban on propagating your own trees without paying him royalties, or can I just buy one and then plant a farm full, or sell my homegrown trees on to others?

Crayz, what you're talking about are plant patents. This is not just "Monsanto-style" - plant patent laws were inspired by the innovation of Luther Burbank. And yes, if you buy a fruit variety protected by a patent and pay a royalty, you are prohibited from reproducing that plant.

Fruit breeding takes an enormous amount of time and effort - in stone fruit, which is where my experience lies, a full decade can elapse between the first cross and the commercialization of a new variety. A well-known stone fruit breeder in California does from the mid- to the high five figures of crosses per year. So paying royalties and restricting propagation, as unfair as it might seem, is a way to keep that pipeline flowing.

Once upon a time, most breeding was publicly funded, and varieties were released from those programs without royalties. As there have been fewer public monies devoted to fruit breeding, more has been done by private breeders, and so they charge royalties.

Not everyone is honest, of course - there are always whisperings about someone or other being engaged in illegal propagation. I suppose it's not unlike any business where the margins are slim and people are tempted to cut corners.
posted by jocelmeow at 1:38 PM on July 29, 2013 [3 favorites]


I believe Driscoll's berries work that way. Those are traditionally bred plants, but that's how farmers get to put "Driscoll's" label on them.
posted by maryr at 2:54 PM on July 29, 2013




If what's missing from the piece is the "this person says A, but this other person says B in response" style of stephanography journalism, and we get actual knowledge and information instead, sign me up for a lot more "missing" parts.

I would like to hear substantial criticisms of this piece, and hear what it's missing. I would like to hear Michael Pollan say something real on this, because I've really respected what he's done for food. I hope it comes.
posted by Llama-Lime at 11:24 PM on July 30, 2013 [1 favorite]


Yeah, I don't actually understand what Pollan is asking in that tweet.
posted by maryr at 8:20 AM on July 31, 2013 [2 favorites]


A new site from UC on asian citrus psyllid, with information for growers and homeowners.
posted by jocelmeow at 9:35 AM on August 20, 2013 [1 favorite]


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