Could The Humble Potato Change Your Image of GMOs?

Hash browns cooking - regular potatoes on the left and the new "White Russet" biotech potatoes on the right

Last week I got my first chance to cook with a "GMO" Potato.  I made one of my favorite breakfast dishes - hash browns!  I was excited to try that with these new potatoes because they have been modified to turn off the gene for the enzyme that makes them turn brown when cut (polyphenol oxidase), or in this case grated.  With regular potatoes, even if you work quickly, the grated potatoes begin to darken before you can get them into the pan.  I've gotten around that by grating them directly into the hot oil, but that is far from ideal in terms of safety.  With these new potatoes I had plenty of time to grate them and shape them.  They turned out not only looking far better, but also came out crispier and better tasting.  It is going to be difficult to put up


These potatoes have been approved for sale and are in many stores, but are not yet in stores where I live.  Colleagues at Simplot Biosciences were kind enough to mail me a bag.  I also posted a video about using this excellent new product.  There is a next generation of potatoes going through the USDA deregulation process.  In addition to the traits that reduce food waste (non-browning/bruising, low sugars in storage) and enhance food safety (reduced acrylamide production during frying), the latest potatoes also have a gene from wild potatoes that makes them resistant to a disease called late blight.  That is what caused the Irish Potato Famine in the 19th century and an issue for potato growing to this day.  The following is the comment I submitted to the USDA in support of deregulation:

(Submitted to USDA on 10/11/16 - https://www.regulations.gov/docket?D=APHIS-2016-0057)

I am writing to support the deregulation of the X17 and Y9 potato lines which involve the same modifications as in previously deregulated lines.  Potatoes are a difficult crop to breed because they only rarely make seed and are polyploid.  While new lines are being developed, there is a substantial advantage of being able to modify older varieties that have proven field performance and desirable characteristics for cooking.  In this case the modified lines are Ranger Russet and Atlantic which are both important commercial varieties.

As with earlier lines, the RNAi gene silencing mechanism has been used to reduce the potential for acrylamide formation during cooking, reduce sugar production during storage which lowers quality, and reducing bruising and browning.  Together the last two traits will help to reduce food waste.  I believe that consumers will also find these potatoes to be quite desirable.

This week I had the chance to cook some of the Russet Burbank cultivar with this non-browning/bruising trait.  I like to make hash browns with fresh potatoes but because of the browning issue I have to grate the potatoes directly into the hot oil.  With these modified potatoes I was able to grate the potatoes and form them into servings prior to frying.  The non-modified potato I used for comparison was definitely inferior in terms of appearance and taste (I've included a picture of the hashbrowns - the upper one is with a standard potato and the lower one is with the down-regulation of the polyphenol oxidase gene.  I will certainly be looking forward to seeing more of these potatoes in commercial channels.

Top hashbrown from a standard Russet Burbank, lower from a White Russet, modified version.

Some critics have implied that the RNAi gene silencing mechanism could have unintended effects.  I believe that this discussion developed by Food Standards Australia New Zealand does an excellent job of debunking the paper by Heinemann et al which is often cited in this context.  Small double stranded RNAs are abundant in the food supply and this mechanism of gene regulation is widespread among eukaryotes.

As a plant pathologist I am particularly excited about one of the traits included in these new potato lines - resistance to the late blight fungus, Phytopthora infestans.  Not only did that disease cause the Irish Potato Famine in the 1800s, it represents a major management burden for potato growers around the world today.  To be able to include plant resistance in an integrated control program will be extremely helpful for potato growers.  The gene, VNT1, comes from wild potatoes native to South America.  To move that gene through conventional breeding would be slow and it would be very difficult to get back to the horticultural and culinary characteristics of desirable potatoes like Ranger Russet or Atlantic. This is an extremely logical application of modern biotechnology and one that would make a great deal of sense for other crops like grapes or coffee which also have pools of genetic diversity which are hard to utilize using conventional or even marker-assisted breeding.

To conclude it makes perfect sense to deregulate this crop as it presents no plant pest risk and substantial societal benefit in terms of food waste reduction and disease management.

A Day Of Accidental Ag Tourism

(This post originally appeared on Better Food Stories 10/3/16)

A few weeks ago I flew to Pasco, Washington and then drove up to Yakima. Eastern Washington is a very dry region, but it has several major rivers and the Columbia Basin Reclamation Project that allow for a flourishing and diverse agricultural industry. My progress was slowed by an irresistible urge to continually exit the main highway to take pictures of these carefully tended crops and to see some of the on-going innovation in planting systems.

A classical, widely spaced orchard

Tree fruits like apples, pears and cherries have long been important to this region. It was fascinating so see some of the innovation used to grow these crops. The image above is from a more classic orchard where large trees are grown with fairly wide spacing between trees and with large swaths between the rows. The next image shows a newer style orchard, in which trees are planted at high density along the row (every 18” or so), and supported by a trellis.

A newer, high-density, trellised orchard

This system gets the trees into full bearing within 2-3 years and can be harvested without the use of ladders (a worker safety and efficiency advantage). The space between the rows is also narrower requiring smaller equipment in terms of tractors, sprayers etc. Note that weeds are controlled in the row with herbicides for water efficiency, and the “middles” support a diverse “cover crop” which stabilizes and feeds the soil.

An alternative "V"shaped trellis system for apples

In the photo above we see a different trellising strategy. In this case, the high density trees are trained in a “V” shape with the goal of even more efficiently capturing the sunlight. Driving further down the road I saw something unusual in the distance and decided to investigate.

An interesting, covered orchard in the distance

It turned out to be another high-density, trellised apple orchard, but in this case it was being grown under a shade cloth to filter the light. This would reduce the chance of fruit getting a “sunburn”, and as you can see, this orchard had an abundant crop of picture-perfect fruit nearing maturity.

High density trellis under shade cloth

Hops

Hops, a highly aromatic plant, have been grown in this region since the 1870s, but even more so of late to meet demand for the booming craft beer industry. Hops are a vine which is trained on very tall (20’ or more) trellises. It is quite impressive to see! From the side of the field (below) it is a giant green wall.

One of the many "hop yards" in Washington serving the craft beer boom

Hops grown on trellises with telephone pole sized supports

Grapes

Washington state is home to a flourishing grape industry with many excellent offerings for wine aficionados. It has also been a long-term source of juice grapes, which is what you see in the vineyard below. Note again the clean vine-row and the cover crop in the “middles.” This is the best way to use water efficiently, build soil quality, and prevent erosion on these hilly locations.

Vineyards

Eastern Washington is also home to many other crops. I’ll just throw in two more examples of a sweet corn field and an alfalfa field.

Sweet Corn 

Alfalfa

The next day I had the privilege to spend time with a number of representatives of the grower organizations and others that support these Washington farmers. The meeting was organized by the Washington Friends of Farms and Forests, which is a grass roots alliance of those who grow the crops or tend the timberlands. I’ll be working with many of these folks for the next few months documenting some of their challenges and strategies tending these diverse plant species for the benefit of the broader society. As always, it was great to see real farming in action!

Why Wheat Is Like Wine

Wheat harvest on the Palouse in Idaho

(This post was originally on the Better Food Stories blog 9/26/16)

There is a term in the wine grape industry called “terrior” which celebrates the fact that fruit quality for wine making is greatly influenced by cultivar, climate and soil type.  Year-to-year differences in weather further influence the quality of specific “vintages.”  Wheat may be a humbler crop, but it is like wine in the sense that there are different classes of wheat for different end-use products and there are different regions where each type excels based on climate (wheat can be hard or soft, spring or winter, red or white, and there is a separate type called “durum” for pasta).  There are even year-to-year differences in quality.  For instance, to make an artisan bread, it is best to use flour from hard red spring wheat, that comes from the northern plains (North Dakota, Minnesota) or from the prairie provinces of Canada (e.g. Alberta and Saskatchewan).  For Asian noodles one wants a soft white winter wheat from the Pacific Northwest.  For crackers a soft red winter wheat is best from a place like Southern Illinois or Kentucky.  For pasta, a distinct type of wheat called durum is used and this is grown in Arizona and in the northern plains.

There are several important measures of wheat quality that reflect important properties of the dough, like strength and elasticity. These properties drive features, like how well the dough will rise and balance of different classes of starch, which influence the texture of baked products.  A yearly report on U.S. hard red spring wheat examines eight categories of “grading” data and eleven measure of “kernel quality.”  53% of U.S. wheat and 60% of Canadian wheat are exported around the world and purchased by customers looking for specific qualities (based on FAOStats data 2011-13). Europe is a major producer of wheat and has much higher wheat yields compared to the lower rainfall production areas in North America, but European countries still import a great deal of wheat for high quality bread and pasta and use much of their domestic production for animal feed.

As with all crops, wheat is attacked by various pests. Unlike grapes, it is possible to deal with some of the pests by breeding resistant varieties of wheat (winemakers are reluctant to accept new grape varieties preferring the traditional favorites that have been in use for hundreds of years).  A key advance in the “Green Revolution” of the 1960s was developing resistance to a particularly damaging fungal disease called “Stem Rust.”  That resistance held up for decades, but in 1999 a strain of the fungus overcame the trait, and since then wheat breeders worldwide have worked to breed a new resistance gene into all the different genetic backgrounds for the diverse wheats grown around the world.

In wet climates, wheat can be infected by many different fungal pathogens and commercial production requires the use of several protective fungicide treatments, starting with seed treatments and spaced throughout the growing season.  In drier North America, diseases are not as problematic, but do sometimes require treatments to preserve yield and quality.  If it rains during the time when the wheat is flowering, a fungus called Fusarium can infect the crop and wheat has proven to be very difficult to breed for resistance. A well timed fungicide spray can help against this disease, but that is not always possible. This particular fungus can produce a mycotoxin chemical in infected wheat kernels called Deoxynivalenol or DON.  It is also called “vomitoxin” because of the effect it has on animals that consume contaminated grain. In our food system, the consumer is well protected from exposure to such toxins, thanks to the care and expense taken on by farmers.

The global wheat industry is really made up of many distinct sub-crops, but as a whole, wheat production has been making steady progress in keeping up with growing global demand with only minimal expansion in planted areas (see graph below).  Some of that progress has been made by diminishing pest damage through a combination of breeding and crop protection agents like fungicides.  Also, a great deal of modern wheat production is in “no-till” systems where weeds are controlled with herbicides instead of by mechanical tillage.  This system greatly reduces soil erosion, lowers fuel use and leads to improved soil health and carbon sequestration.

The green part of each par shows the proportion of the increased production achieved through higher yield rather than additional planting area

So the next time that you enjoy a wheat-based product, think about the effort and risk that a wheat farmer faced, not only to produce the grain, but to produce it with the positive qualities needed and with the absence of issues like DON toxin.