Is it currently possible to engineer a virulent crop blight?

Inspired by this GD thread:

Kix brings up an interesting point:

Is such a thing currently possible? Could we or an adversary (or have we already) engineer a bio-weapon that would introduce a virulent crop blight that could take out all/much of the corn/wheat in the Great Plains? I’m thinking something that could be spread on the sly by spies in a few different areas early in the season, that would then spread and kill the rest.

Granted, we have pretty big-ass surpluses, so even one year’s crop failure wouldn’t mean the death of everyone in the US (though it would obviously strain us and probably necessitate early livestock slaughter for lack of feed), but is such a weapon possible with current technology and expertise?

Why do you think killing off the corn and wheat or even soy for that matter would mean starvation anyway?? I’m alergic to wheat, I’d be psyched!

Even if you had a virulent strain of something horrible, I’d say it would be near impossible to infect an entire seasons crop. Ever driven through eastern Montana, all of Nebraska and Kansas? A sea of wheat/corn/soy. Not a few miles of it, but thousands of square miles of it. IMHO such a weapon could not work. At least not on the scale you are talking about.

well, no corn (and sorghum, I guess) means no animal feed means much less meat, dairy, eggs, etc.

Are there rice blights? It’s such an innocuous plant … no allergens, after all …

This monoculture is why I think you could have problems. Endless sea of exactly the same thing …

But I have no idea how tough it would be to engineer, or if there’s anything similar to the potato blight that could hit cereal crops. I suppose they could seed the area with gabillions of grasshopper eggs … plague of locusts.

Could you engineer a crop blight? Sure. Crops can be affected by bacteria, viruses and fungi, all of which should be pretty easy for an experienced bio-terrorist to whip up.

Would it immediately doom the United States to famine? Not likely. As Coda points out, there’s a LOT of cropland, hundreds of millions of acres. Crop blights tend to spread relatively slowly (famine-wise, that is.) Citrus canker sore has been spreading through Florida for years, and last time I heard, hadn’t made it as far north as Orlando yet.

Plus there are many different varieties of the major crops. Some varieties would likely be more resistant than others, and the major seed companies would soon (possibly the next season, probably not more than 2) have blight-resistant varieties generally available.

  1. Is it possible? Yes. The costs would be great though.
  2. Would a terrorist do it. Probably not with the cost compared to other methods available. Plus why do something that people would blame on God.
  3. I wouldn’t be so quick to dismiss the possiblity of infecting an entire seasons crop. While dispersment of the blight would be needed history has shown an entire country’s crop to be destroyed by a natural blight. Coda does rightly point out that only one type of crop would be destroyed.
  4. We may do it ourselves accidentally.

Plant pathogens tend to be quite picky about temperature, humidity, host plant genome etc. Back in 1970 when Bipolaris Maydis (nee Helminthisporium) ravaged the US monoculture of Texas male sterile corn, it only detroyed about 15% of the crop. That amounted to a major disaster, but no one starved because of it. AFAIK, we haven’t done much research into producing more tolerant, deadlier plant disease agents.