I loved the movie Interstellar. From the very first time I saw the trailer, I was hooked. I could not wait to watch the movie after hearing Mr. Alright Alright Alright talk about how we used to be dreamers and explorers with images of space exploration playing across the screen.  I’m a sucker for space operas and science fiction movies in general. In the beginning of Interstellar, we see how the Earth of the future is different than our own. How there was this “blight” that was wiping out our staple crops, such as corn or soybeans. This was scary in itself, but also because it was actually grounded in science. With our world being ever interconnected and mono culture crops reigning supreme, we are in a good spot, or rather a bad spot, for such things to happen. Good thing it was only a movie.

The “blight” was doing more than just taking the food off of peoples’ tables. It was also destroying how they thought of themselves. When they previously were able to support their families, one morning they’d wake up to find it all gone. Generations of tending, nurturing, and back-breaking sweat, and it was all gone in the blink of an eye. It was unfair, and it was heart-wrenching to think about. You can imagine the billions of dollars in damages, thousands of jobs lost, and the paralyzing fear that comes from not knowing how to stop this blight.

Before we move on, let’s recap: the destruction of crops, billions of dollars in damages, and no hope in sight. It’s a good thing this is just a movie, set in the far future.  We should have plenty of time to ensure it won’t happen to us. Should being the operative word if we lived in a perfect world. But it’s not a perfect world. While the futuristic blight in Interstellar is fictional, we have already been facing our own blight in the United States for almost ten years. This is the story of Citrus Greening, which has been rocking the citrus (i.e. oranges, lemons, etc…) industry for nearly a decade. Read on to learn for yourself.

 

Citrus Greening ( Huánglóngbìng or HLB)

The United States Department of Agriculture probably says it best with, “one of the most serious citrus plant diseases in the world…Once a tree is infected, there is no cure.”1.   HLB is thought to be a bacteria that is transmitted two different ways: from tree-to-tree through the Asian Citrus Psyllid(ASP) or through grafts taken from already infected trees. As the name Asian Citrus Psyllid might suggest, this disease is not native to to the US, but was brought here. You can think of it as similar to the Zika virus, in that it’s transmitted through a bug that acts as a host as it goes about its natural life processes. This is the same process. ASP is being used by the disease to thrive and grow.  You’re probably asking, “how big of a problem is this, or, is this just a local problem since I haven’t heard of it before?” To give you context, in 2007/2008, when HLB was first being detected in the US, we were producing close to 14 million tons of citrus in places like Florida, Texas, and California.  Today, 10 years later, we are projected to produce around 6 million tons of citrus (See Figure 1). That’s about a 57% decrease in production, or 8 million tons of missing citrus, and it looks like it’s getting worse.

In Florida alone, which is known for being the orange state, there has been about an 80% decrease. That’s huge. Whenever I think of Florida, I think of blue crabs, Disney World, and oranges. They put the orange on pretty much every sign, and people who have driven through the state can attest to that.  To have their staple crop reduced to only 20% of previous years is absolutely astounding.

And that’s just in Florida. To zoom out again to the national level, we have had a 57% decrease,  8 million tons of citrus destroyed, and billions of dollars in damages. So, you must be asking, “what are we doing to stop this?!”.

 

 

Actions We Are Taking

For thousands of years, the basic thing we could do to combat the spread of disease was quarantine.  In the Middle Ages, ships that were being attacked by the plague would raise a special flag, and have to wait it out, anchored just offshore. By wait it out, I mean wait for the infected to die or recover, and then wait for the disease to do the same. Today, much like our ancestors, quarantine is one of the most effective methods we have for containing this horrific disease. It’s a part of a larger strategy to fight this illness, such as  antibacterial management, education programs, removal of infected trees/plants, and frequent surveying. These are all good efforts, but are still only half the equation in a modern plan to fight a disease like this. A hundred years ago, the citrus would most likely have been doomed to being brought low like we were by the plague in the Middle Ages. Today, we have amazing technology, such as genetic engineering with gene drives and altering host characteristics, to prevent the spread of this illness. There is money being earmarked to find new ways to fight this disease in the Farm Bill as well, which tells you how seriously this is being taken. In the meantime, researchers are working to better understand it, fight it, and stop it. While we wait, we can use the methods mentioned above and also help spread the word. For those in impacted states (see figure 1), here are the key signs to look out for, so you too can be part of the process in using the most effective method we have right now. Quarantine.

 

Signs

1. “Early symptoms of HLB on leaves are vein yellowing and an asymmetrical chlorosis referred to as “blotchy mottle.” “(2)
2. “Leaves may be small and upright” (2)
3. “Some leaves may be totally devoid of green or with only green island” (2)
4. “Visible psyllids or waxy psyllid droppings” (3)
5. “Lopsided, bitter, hard fruit with small, dark aborted seeds”(3)
6. “Fruit that remains green even when ripe”(3)
7. “Asymmetrical blotchy mottling of leaves”(3)
8. “Yellow shoots”(3)
9. “Twig dieback”(3)
10. “Stunted, sparsely foliated trees that may bloom off season”(3)

Is This The End?

Both for this blog and podcast series, and for citrus, the answer is categorically no. This is not the end. This is the beginning.  Citrus has the benefit of great researchers, the US Agriculture Department, modern technology, and each of us reading this. If we could stop the plague with quarantines hundreds of years ago, then we can stop this using similar methods and modern advances that are changing the way we do business when it comes to the prevention and eradication of disease. Additionally, this is the first part in a multi-part series, culminating in a podcast episode with the leading experts describing their work, Citrus Greening (Huánglóngbìng or HLB), and what has been going on (akin to a Radiolab or Freakenomics style episode). Stay tuned for that and for the other parts of this blog series, and please share this. We all need to do our part in raising awareness. 

 

If you liked this post you might also enjoy these podcast episodes as well. 

1. Next Generation Insect Crop Innovation Startup, Beta Bugs, and Founder, Dr. Thomas, to Create Next Generation Feed, Food, and Fuel
2. Extinction, Vaquita Porpoise Conservation, and SAFE Food Label Discussion with David Bader the Director of Education at Aquarium of the Pacific
3. Cellular Agriculture, Clean Meat, Developments, Building a New Industry, and How to Get Involved With New Harvest Research Director Dr. Kate Krueger
4. Penguin Expert, TED speaker, and Author of The Great Penguin Rescue Dr. Dyan DeNapoli Discusses Going back to School at 30, Pollution, and Penguin Conservation
5. Whale Talk, Whale Facts, Whale Falls, Seafood Rules of Thumb, and Conservation Practices with Aquarium of the Pacific Education Coordinator James
6. Bloody Fat Popsicles, Polar Bears, Conservation, Life in the North, and Career Progression with Alysa and BJ Who are Directors at Polar Bears International
7. Elizabeth Stulberg, Science Policy Manager the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America Part 2
8. Elizabeth Stulberg, Science Policy Manager the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America Prt 1

A special thank you to Dr. Elizabeth Stulberg, who has been featured on this podcast two times (episode 8 and 9). And to my best friend Amy for helping me with my horrible commas and capitalization.