Wednesday, August 28, 2013

When A Genetic Solution Saved The French Wine Industry

The mid to late 1800s was a very difficult time for the European wine grape industry.  New pests associated with native North American grape species made their way to the "Old World" because of transport between the continents.  I recently wrote about how a fungal disease called downy mildew nearly destroyed the industry until it was saved by the accidental discovery of an effective chemical fungicide.

In today's post I'm going to talk about an insect pest that was introduced to Europe in the same era.  It was a a root feeding relative of aphid called Phylloxera.  Native American grapes are quite tolerant to it, but when it started attacking the roots of the European, Vitis vinifera grapes it began debilitating and finally killing the vines.  It may have arrived in the 1850s, but was first recognized in 1863.  This was an extremely trumatic economic and social crisis.  More than 1 million hectares of vines were killed and many more debilitated before a solution was finally found. In this case the ultimate solution was found via genetics  (There are many good sources about the extended drama and real economic suffering associated with this this crisis - see links below)
1888 drawing of what is now classified as Daktulosphaira vitifoliae

The Genetic-based Technology Solution

The solution to Phylloxera that was ultimately applied seems obvious with hindsight.  Since the North American grape species had always tolerated this pest, why not use them as "rootstocks" and graft the revered European varieties on top of them?  Grafting of desired varieties onto the roots of less desirable, but either more hardy or already established versions of the same crop was not a new idea.  That had been practiced for thousands of years for many tree and vine crops.  The ancient Hebrew and Christian scriptures are full of literary images based on the concept of grafting.  It was an ancient, practical solution - but what it amounted to was a rather dramatic "genetic modification" of the roots of millions acres of European grapes (and eventually grapes around the world).

This idea of grafting onto foreign, low quality grapes was hard to swallow for much of the French wine community of the day.  Their questions included:

  • Will treasured, traditional varieties like Pinot Noir grafted on this inferior sort of grape still make a classic red Burgundy worthy of each specific appellation in that district?  
  • Will this new reality mess with the quality that was traditionally achieved with complex blend of varieties in a region like Bordeaux?
  • Will this new pest eventually overcome this solution?  
  • Should wine made from grapes grafted on American rootstocks be labeled as GMO?
Ok.  They didn't ask the last question in the 1800s, but there was a long-running and eventually meaningless debate about whether pre-Phylloxera wines were better.

An Ironic Modern Rejection of a Genetic Save for Grapes

Flash forward to modern times.  There is a nematode pest which spreads a grape disease called Fanleaf Virus.  Once the soil on a given site has been contaminated with that small, roundworm parasite and the virus, if you plant vines there, even after ten years with no grapes, after a few years they decline and die.  This is actually a problem nearly as old as Phylloxera, but fortunately it does not spread easily.  Once people understood how it works, it has been mainly limited to certain areas in France, some other European countries, and a few places in California.  The sad part is that there are significant hectares of vineyard sites in premium wine growing districts that can't be used to make great wine because of this issue.  For many crops, one can just move away from such problems, but for wine the unique combination of climate and soil can create conditions which are legitimately important for quality.  The term "Terroir" is used to describe that essence of place.  Fanleaf virus and its vector severely compromise the Terroir wherever they occur.

With the advent of biotechnology there was the possibility of a better solution for Fanleaf contaminated sites that never existed before (there were some nematode resistant rootstocks but they were undesirable for other reasons).  A rootstock was developed which was resistant to the virus using the same approach that saved the Hawaiian papaya industry.  With that genetic solution, high quality grapes could be successfully grown on on compromised sites in a way directly analogous to how American grape rootstocks saved the crop from Phylloxera in the 1800s.

One might imagine that with the tremendous esteem for terroir in the wine French wine industry, this means of rehabilitating highly valued vineyard sites would be eagerly embraced by the wine industry. Unfortunately that was not the case.  There were some modest field tests of this rootstock being conducted by a French governmental agency in 2010.  There was a great deal of public controversy about this, little industry defense, and ultimately activists destroyed those trials on August 15, 2010.  Their stated concern was that this new rootstock could "genetically contaminate" the rest of the grape crop.  Let me explain why that fear was irrational to an absurd degree:

As this post describes, back in the late 1800s, the entire French and European grape crop was replanted on American rootstocks which differ from the Vitis vinifera grapes by probably hundreds of genes or versions of genes.  No one has ever needed to worry about "genetic contamination" from those millions of acres of genetically "foreign" rootstocks even though they have been present for over 100 years.  If those industry-saving American rootstocks (which are normally only underground) ever happened to get the chance to flower and generate pollen, it still wouldn't matter because grapes are never grown from seed. They are always grown from cuttings or buds.  That is also why you can plant blocks of different grape varieties side by side with no issue of "contamination."  So why would rootstocks with ONE very useful gene inserted by genetic engineering suddenly be a contamination risk?  There was absolutely no risk!

As far as I can tell, the grape industries in France and elsewhere were sufficiently intimidated by the magnitude and ferocity of the irrational response to have decided to simply live with some of their best vineyard sites being compromised. If someone in those industries knows differently, please let me know.

You are welcome to comment here and/or to email me at  I tweet about new posts @grapedoc

grape image mine
Phylloxera drawing from Wikimedia Commons

There are many websites which describe this traumatic event for the European grape industry and for the economy as a whole (Wikipedia: Great French Wine Blight, a review of what sounds like an interesting book about this by Christy Campbell,  a nice summary from 1986 in Wine Tidings republished  by The Wampum Keeper).

Wednesday, August 21, 2013

When A New Technology Saved The French Wine Industry

Amy Harmon's excellent, recent article in the New York Times describes how the Florida orange juice industry may soon be wiped-out because of a new bacterial disease spread by an introduced insect.  It looks like there could be a technology-fix for the problem using genetic engineering.  The question is whether the growers will get to apply that solution.

Coffee Rust - later these infected leaves fall off

The sort of crisis situation now facing the Florida orange industry is not at all unique in the history of farming.  There have been many times when some new pest  threatened the economic viability of a major crop.  Sometimes the pest "wins" and a particular farming industry simply goes away.  In the mid 1880s when Coffee Rust made it from Africa to the coffee plantations that supplied England from Java and Sri Lanka, the industry collapsed, and so the English had to switch to tea to get their caffeine.  When Wheat Stem Rust made it too hard to grow wheat in the Southern colonies of what would later become the US, the farmers shifted their cropping to cotton and tobacco.  That involved much higher labor requirements which in turn lead to the sad institution of slavery in that region.

But there have been other times when some new technological breakthrough has saved a threatened crop, as it possibly could for the Florida orange growers.  I'll give just one example here.

Back in 1874, a plant scientist name Pierre Millardet was walking down a road in Bordeaux France.  The famous vineyards he was passing were being devastated by a fungal disease called downy mildew.  It had been unwittingly brought across the Atlantic by the British who came back with specimens of the wild grape species they found in North America (e.g. Vitis labrusca - Concord types).  Those grapes harbored the downy mildew which was not too problematic for them, but the Vitis vinifera grapes of the Old World were extremely susceptible.  The wet climate of Europe was also ideal for fostering the fungal epidemic.
Grape downy mildew symptoms. Later leaves fall off.  Fruit can be effected too

Millardet was very concerned about this problem as were all the French looking at the possibility of not continuing to be able to produce wine.  As he walked past vineyard after vineyard nearly defoliated by the disease, he came upon one small part of a vineyard that looked remarkably healthy.  He quickly sought out the owner to ask why those vines looked so good.  It turned out that the grape grower had been frustrated by the fact that so many passer-bys on the road would help themselves to his grapes as they ripened.  He had concocted a mixture of copper sulfate and hydrated lime and sprayed it on the grapes to make them less attractive.
What the Bordeaux mix looks like sprayed on tomato leaves

By accident the farmer had developed a reasonably effective fungicide.  Millardet promoted that option, and soon the "Bordeaux mix" saved the French and other European grape industries.  It also saved the European potato crop which was also being devastated by a related disease that belatedly followed the potato from its origins in the Andes and caused the epic Irish Potato Famine.

Fortunately today we have many superior fungicide options to protect these crops.  Copper-based fungicides were "state of the art" in the 1870s, but by modern standards they are rather toxic to mammals, persistent in the environment, and bad for aquatic invertebrates.  One of their remaining uses is for organic farming which has only a few fungicide options that qualify as "natural."  New, synthetic fungicides that protect grapes, potatoes, wheat and other crops in Europe and elsewhere are far better for health and the environment. Still, without the accidental discovery of the "Bordeaux Mix," the European wine grape industry could have disappeared.

I gave an invited talk for the Specialty Coffee Association and its annual symposium back in February. The Arabica coffee growers in the highlands of Central and South America are facing a severe, new threat from a disease called coffee rust.  My role at the the conference was to put that crop threat into a global and historical perspective.  This grape disease story is one of the examples in my talk titled: "Humans vs Pests, The Long View."

You are welcome to comment here and/or to email me at  I tweet about new posts @grapedoc

Orange grove image from USDA-ARS
Coffee Rust (Hemileia vastatrix) image from Smartse
Grape Downy Mildew (Plasmopara viticola) image from the University of Georgia Photo Archive
Bordeaux mixture residue image from the Tomato Lover blog

Thursday, August 15, 2013

In Which My Grand Daughter And I Became Flower Rescuers

My favorite fellow flower rescuer in action
One of the fun aspects of grandparenthood is getting up to speed with what is on children's television.  My personal favorite is "Shaun The Sheep," but one of my grand daughters Kay's favorites is "Go Diego Go."  Diego is a little kid that has adventures as an "animal rescuer."  The show tends to give the impression that wild animals can't really do very well without help, but at least it does expose kids to some biology.  Because of watching Diego, at 3 Kay can go to the zoo and accurately identify anything from a macaw to a pigmy marmoset.  But back to the flowers.  Here is the tale of how Kay and I became "flower rescuers".

For you Grandma!
About a quarter mile from our house there is a commercial greenhouse.  It is one of the few remaining floriculture operations from what was once a big industry here in northern San Diego County.  They produce beautiful gerbera daiseys for cut flower sales.  When they can't sell all they pick on a given day, they dump them for informal composting on an open area that Kay and I pass when we go for walks during her summer visits to Grandpa and Grandma's house.  She liked to scoop up bunches of flowers to take back to Grandma.  When I said she was a "flower rescuer" she loved the concept (These flowers recovered really well and lasted in a vase for several days).

Whole plants in the background during this rescue trip

On one of our visits to the flower graveyard we found hundreds of large gerbera daisy plants rooted in eight inch cubes of rock wool - a soilless growing medium that is used in the greenhouses.  It turns out that there was an infestation of "leaf miners" in the greenhouse and the grower was purging his supply to get rid of them.  Leaf miners are a nasty pest.   I certain kind of fly lays its eggs in the leaf and the larvae that hatch then burrow their way around inside of the leaf until they grow large enough to emerge as adults and repeat the cycle.  Many insecticides are useless against these pests because they are inside of the plant and not easily reached.

Leaf miner damage

Kay hated the idea of seeing the whole plants strewn in piles and dying, so I agreed to try to rescue some of them.  
Strollers can be good flower rescue vehicles

Saved gerberas after the dead and insect infested leaves were removed
We took the plants back to the house, cut off all the miner infested leaves, and planted these big plants in our flower beds.  It took a week or so to get the plants adjusted to being outside instead of in the greenhouse.  Some of the plants also had powdery mildew infections (a fungal disease) that I killed with some dilute dish soap (powdery mildews grow on the surface of leaves, so they can be killed with any surfactant if you have time to thoroughly apply it to both sides of every leaf).  Then with some fertilizer the plants began to thrive - producing their large flowers that are good for a week as a cut flower or even longer on the plant.
Happy transplanted gerberas on terraces in my backyard
Conscious of the fact that I am growing these plants close enough to the greenhouse for pests to move, I've also treated my plants with a nice product that is finally available to homeowners called "3-in-one Insect, Disease and Mite Control" that comes from Bayer.  It is for use on ornamental plants and it includes the systemic actives imidacloprid (something that would take care of any more leaf miners), tau-fluvinate (that would take care of mites), and tebuconazole (a fungicide which would prevent more powdery mildew in the future).  Don't worry about the imidacloprid hurting bees - I've watched and they don't visit the gerberas.  I'm now confident that I'm not putting the new flowers at the greenhouse at risk by planting them all over my yard.

I love having the chance to teach my grand daughter about plants, and I'm happy that she thinks being a "flower rescuer" is cool.  I'm enjoying that role as well.

You are welcome to comment here and/or to email me at  All images on this post are mine.  I tweet mostly about new posts @grapedoc.

By the way, if you are familiar with Go Diego Go or the related show Dora The Explorer, you should really see this faux trailer for a movie about Dora grown up

Tuesday, August 13, 2013

Is There Really GMO Pot?

"Blimey, is that GMO?"

An interesting issue came up through my volunteer work for the new website, "".  Apparently some pot users are concerned that they might be unwittingly consuming what they consider to be a dreaded "GMO."  The irony is that while marijuana has definitely been "genetically modified" to contain higher levels of THC, that change didn't involve the tools of modern biotechnology. Instead, the changes were achieved using rather clumsy methods from the past.

New plant varieties have often been based on chance mutations in their DNA.  For instance the sweet corn varieties we enjoy today include a mutation that allows them to retain their sugar content after picking. In the 1950s and 1960s many plant breeders employed "mutation breeding" to increase the chances of finding DNA changes that would result in new traits.  They exposed the plants or seeds to doses of chemicals or radiation that would cause random mutations, and then looked for the rare cases where there was some desirable effect.  They would also use the toxic chemical colchicine to induce the plants to double their number of chromosomes, something that sometimes leads to more vigorous growth.  These same methods were quite successfully employed by the extra-legal marijuana industry over the last few decades.

Both mutation breeding and chromosome doubling can lead to genetic changes which are undesirable but which remain undetected.  If you go through the list of "what ifs" that are typically raised by the opponents of genetically engineered crops (new allergens, changes in regulatory pathways or other patterns of gene expression...), these old methods are far more likely to create such problems. Unlike a modern biotech crop where the exact nature of the genetic change is known, we really have no idea what all has changed in crops improved using these "old school" methods. (Kevin Folta posted an excellent comparison of transgenics and mutation breeding)

However, the crops developed using these clumsy tools have never been regulated or safety tested like biotech crops.  They qualify for use in organic farming.  Such crops would not have to be labeled under the various bills and initiatives that have been proposed.  Now the truth is that foods developed using these old methods have a decent track record of safety.  But applying the same "you never know about long-term effects" logic used against biotech crops, we really can't be sure they are ok, even after decades.  I guess the advantage is that you are less likely to worry about such questions after partaking in some mutant, highly-ploidy weed.

Cannabis raid image from the West Midlands Police

You are welcome to comment here and/or email me at
I tweet about new posts @grapedoc

Monday, August 5, 2013

A Week On An Island Of Angst

I've just returned from a week on Kauai.  It is known as "The Garden Isle" of the Hawaiian chain, but recently that garden has been heavily sown with seeds of fear, suspicion, and conspiratorial narratives. On Wednesday, the 31st, there was a marathon session of the County Council during which hundreds of people lined up to give testimony about Bill 2491 from 1 pm until midnight.  Angst was a common theme. The activist speakers made hyperbolic assertions about heartless corporations perfectly willing to sicken the entire population of the island and destroy the environment. Many non-agricultural residents expressed their palpable fear for the safety of their families.  Some of the employees of the seed or coffee companies tried to explain to their fellow islanders that they and their families also live there, and so they would never want to put either their families or neighbors at risk. These people have good reason to worry about the future of their jobs.

This Is Actually About Biotech, But...

Kevin Folta, head of the horticulture department at the University of Florida, was there for the week to represent a truly independent, scientific perspective on the safety of biotechnology.  He was quite effective because of his willingness to engage in dialog with even the most dedicated wing of anti-GMO camp.   I was there to offer some perspective on the pesticides used.  Activists are targeting the biotech industry, but the primary means through which they have been generating fear has been by talking about a list of "Restricted-use pesticides" employed by the coffee and seed industries. 

Strategically, the focus on pesticides makes perfect sense for the activists.  Unlike plant biotechnology, pesticides had a "bad old days" during which legitimately scary things happened.  In the present campaign, these sorts of events are highlighted without any perspective on how much change there has been over the last 44 years since the EPA was established in 1970.

Most people know something about the dramatic improvements society has seen since that particular era when it comes to automobile safety, control of exposure to secondary smoke, protection against egregious manifestations or racial and gender discrimination.  Most people have a concept of how far we have come since the 1960s with regard to a host of technologies in medicine and electronics.  What is unfamiliar to most people outside of agriculture is that there have been comparably dramatic improvements with respect to the safety of agricultural pest control technologies.  For the most part, only farmers have witnessed this change.  Others doubt the progress on the regulatory front, convinced that all regulatory agencies have either been bought-off by nefarious industry influence or rendered impotent by funding limitations.  Anyone who has worked in a heavily regulated industry like farming or pesticide manufacturing knows otherwise, but that knowledge base represents a tiny fraction of the population.

At the hearing (and in public forums, press interviews and meetings with business leaders), I simply attempted to use data from transparent, public sources to put what are actually not-so-scary-pesticides into perspective (see a previous post with more details).  That was helpful, but only in settings where were able to have a real conversation.  I think the most effective way for people to relieve their angst is to take the seed companies up on their offer to provide tours of the research farms so people can see first-hand the sort of safety precautions used and the extensive documentation required to meet regulatory requirements for multiple agencies at the federal, state, and county level.  Inexplicably, the council members who introduced Bill 2491 have yet to take such a tour. Why try to understand something you try to legislate against? 

What I witnessed at the Council Hearing suggested how politically difficult it is going to be for other local elected representatives to resist the pressure to legislate based on fear rather than facts.  The activists are also expanding the campaign of fear to discourage the tourist industry, which is actually the life-blood of the local economy.  Can they generate as much angst there as they have with residents? Tourists may be harder to reach, but in an on-line age when many people's standard of truth has become, "I saw something about that on the internet," it is sadly possible.

As my plane climbed to afford me a last, beautiful view, I thought back to the first time I visited Kauai in 1993, only months after the devastating blow from Hurricane Iniki.  At that time, broken-over trees still dominated the landscape.  The natural systems of the island are self-healing and the evidence of that storm is now essentially gone. The current storm of activism impacting Kauai is a campaign that claims to be about stopping the "poisoning of paradise." The human experience of that paradise is an experience of the mind informed by the senses. That potential joy has indeed been poisoned by the intentional mass-cultivation of angst on the Garden Island. 

You are welcome to comment here and/or to email me at  I tweet about new posts @grapedoc

Image of  "The Scream" by Edvard Munch from CHRISTOPHER MACSURAK
Protester image my own