UF researchers exp breakthrough approach to combat devastating citrus greening

[GFC]

Very welcome news

https://www.gainesville.com/story/news/2025/01/09/university-of-floridas-ifas-works-to-combat-citrus-greening/77551490007/

[chris03]

I worked in the Millenium block for a few years. It's a great trial to show how scions and rootstocks interact and impact traits like vigor, yield, and tolerance, but I am almost certain that nothing in there is the solution to greening unfortunately. They do have some pretty decent grapefruits in there, ill be visiting them tomorrow. For a few years their number one tolerant cultivar was some kind of red grapefruit, since I was out there almost daily I learned to differentiate on leaf shape, growth habit, etc. and I was able to identify that they were a set of mislabeled trees.  Glad to see the millenium block getting some attention on the forum! 
Heres a pic I took some years back!

[NateTheGreat]

GMOs.

[Coconut Cream]

It would be great to figure something out to combat the greening, but would a citrus fruit with a gene insertion really fly with consumers? I can smell the boycott already. Imagine going through all that work and then the end product flops in the marketplace. "Enjoy A Genetically Altered Florida Citrus Fruit Today!"

Maybe it's better to just move on to other crops and spend the budget on educating kids and consumers what we can grow here instead of citrus and that so much of it is much more exciting.

[roblack]

Interesting. An extra bacterial gene may be preferable to systemics, but I am not knowledgeable on these matters. Happy Orri citrus is arriving tomorrow though.

[greg_D]

There's an HLB curative coming. It involves injecting a peptide isolated from an Australian citrus species into the trunks of the trees. One of the researchers working on it gave a talk roughly a year ago at the local botanical garden here in Los Angeles.

[Galatians522]

They have had GMO trees immune to greening for 10+ years. I think it was a spinach gene they spliced in back then. I don't want a GMO orange personally. The CUPS screen structures are working out great. We just can't afford to produce juice oranges in them. So, they will be for fresh fruit only (unless someone finds a cheap construction method). That means we will be saying good bye to ~90% of our citrus acreage sooner or later.  :'(

[CThurst83]

They have had GMO trees immune to greening for 10+ years. I think it was a spinach gene they spliced in back then. I don't want a GMO orange personally. The CUPS screen structures are working out great. We just can't afford to produce juice oranges in them. So, they will be for fresh fruit only (unless someone finds a cheap construction method). That means we will be saying good bye to ~90% of our citrus acreage sooner or later.  :'(

HLB was just detected in my city a month ago. I would be ok with GMO citrus as long as there are no health concerns ( is that what the issue is?). If there is a method to protect existing trees with injections prior to infection I would use it on my five trees.

[bovine421]

They have had GMO trees immune to greening for 10+ years. I think it was a spinach gene they spliced in back then. I don't want a GMO orange personally. The CUPS screen structures are working out great. We just can't afford to produce juice oranges in them. So, they will be for fresh fruit only (unless someone finds a cheap construction method). That means we will be saying good bye to ~90% of our citrus acreage sooner or later.  :'(

HLB was just detected in my city a month ago. I would be ok with GMO citrus as long as there are no health concerns ( is that what the issue is?). If there is a method to protect existing trees with injections prior to infection I would use it on my five trees.

I miss my Persian lime tree casualty of citrus green so I believe. As I sit here eating my GMO Corn Flakes I would be okay with a fortified citrus tree.

[Galatians522]

I went back and checked for the article about the "spinach tree." It was not immune, just resistant and was produced back in 2015. They said back then that they were essentially focusing on a GMO solution.

I believe that the real problem with GMO is that we don't really know what we are doing and what the long term effects will be. Genetic discontinuity is a major driver for infertility and diseases such as cancer. For example, they say not to drink scalding hot coffee because it could causr cell damage that leads to cancer.

Splicing one or two genes into a tree will probably not cause much loss in fertility. Once GMO becomes a common place solution to every possible malady, we will see a major yield loss and possibly new diseases that we have never seen before and that will have no simple solution. Sometimes we outsmart ourselves.

I don't mean to sound like a worry wort. I loved my citrus trees as much as anyone else. But I don't think the risk is worth the reward in this case. There are highly resistant citrus varieties with resistance so high they are almost immune. We need to capture those genes through conventional breeding and genome analysis screening (if the seedling does not have the resistance gene it gets thrown). The issue seems to be that this route is "much hard work."

[countryboy1981]

They have had GMO trees immune to greening for 10+ years. I think it was a spinach gene they spliced in back then. I don't want a GMO orange personally. The CUPS screen structures are working out great. We just can't afford to produce juice oranges in them. So, they will be for fresh fruit only (unless someone finds a cheap construction method). That means we will be saying good bye to ~90% of our citrus acreage sooner or later.  :'(

HLB was just detected in my city a month ago. I would be ok with GMO citrus as long as there are no health concerns ( is that what the issue is?). If there is a method to protect existing trees with injections prior to infection I would use it on my five trees.

I miss my Persian lime tree casualty of citrus green so I believe. As I sit here eating my GMO Corn Flakes I would be okay with a fortified citrus tree.

And people wonder why colon cancers are rising.

[bovine421]

They have had GMO trees immune to greening for 10+ years. I think it was a spinach gene they spliced in back then. I don't want a GMO orange personally. The CUPS screen structures are working out great. We just can't afford to produce juice oranges in them. So, they will be for fresh fruit only (unless someone finds a cheap construction method). That means we will be saying good bye to ~90% of our citrus acreage sooner or later.  :'(

HLB was just detected in my city a month ago. I would be ok with GMO citrus as long as there are no health concerns ( is that what the issue is?). If there is a method to protect existing trees with injections prior to infection I would use it on my five trees.

I miss my Persian lime tree casualty of citrus green so I believe. As I sit here eating my GMO Corn Flakes I would be okay with a fortified citrus tree.

And people wonder why colon cancers are rising.

Just dumped out my Frosted Flakes you do have a valid point. Back years ago there was a lot of lawsuits brought on Monsanto by different states. Must have been some hush money donated. Don't really hear too much about it anymore. Thing I remember from back during that time frame was the Mexicans and the Russians didn't want our hybrid corn because it would contaminate their true seed by the pollen drifting in the Wind. Making their Native Seed corn sterile

[countryboy1981]

They have had GMO trees immune to greening for 10+ years. I think it was a spinach gene they spliced in back then. I don't want a GMO orange personally. The CUPS screen structures are working out great. We just can't afford to produce juice oranges in them. So, they will be for fresh fruit only (unless someone finds a cheap construction method). That means we will be saying good bye to ~90% of our citrus acreage sooner or later.  :'(

HLB was just detected in my city a month ago. I would be ok with GMO citrus as long as there are no health concerns ( is that what the issue is?). If there is a method to protect existing trees with injections prior to infection I would use it on my five trees.

I miss my Persian lime tree casualty of citrus green so I believe. As I sit here eating my GMO Corn Flakes I would be okay with a fortified citrus tree.

And people wonder why colon cancers are rising.

Just dumped out my Frosted Flakes you do have a valid point. Back years ago there was a lot of lawsuits brought on Monsanto by different states. Must have been some hush money donated. Don't really hear too much about it anymore. Thing I remember from back during that time frame was the Mexicans and the Russians didn't want our hybrid corn because it would contaminate their true seed by the pollen drifting in the Wind. Making their Native Seed corn sterile

Roundup has antibiotic properties at least to some types of bacteria:

Samsel and Seneff also postulate that glyphosate disrupts the biosynthesis of aromatic amino acids by gut bacteria, based on a study showing a decrease in amino acid levels in a carrot cell line exposed to glyphosate (21). Although it can be hypothesized that glyphosate may disturb the gut microbiome because some bacteria possess the EPSPS enzyme and shikimate pathway, and thus may indirectly affect aromatic amino acid biosynthesis, this has never been studied in a controlled laboratory animal experiment. Indeed, the patenting of glyphosate as an antibiotic to be used against a wide spectrum of microorganisms was based solely on effects in protozoa (not bacteria) and its effectiveness was dependent on the addition of di-carboxylic acids (US Patent No. 7771736 B2). At this stage, it is currently not clear whether glyphosate has an effect on the mammalian gut microbiome, especially at environmentally relevant levels of exposure. Nonetheless, some studies have shown that glyphosate and glyphosate-based herbicides such as Roundup can selectively affect bacterial populations in vitro (22) while others have reported no adverse effects (23). Given these discrepancies additional research is clearly needed to ascertain whether glyphosate-based herbicides at environmentally relevant levels of ingestion can result in disturbances in the gut microbiome of human and animal populations with negative health implications.

https://pmc.ncbi.nlm.nih.gov/articles/PMC5705608/

[greg_D]

With GMO stuff I don't think it makes sense to categorically accept or reject the concept. For example, it is known that an Australian citrus species produces a peptide that helps with HLB. In theory, you could cross that Australian citrus species with navel orange, then spend a really long time doing back crossing, trying to somehow end up with a citrus that has the gene(s) to produce that peptide from the Australian citrus yet otherwise is a navel orange. It would probably take an enormous amount of time and effort. Alternatively, if you could use CRISPR to insert the relevant gene from the Australian citrus tree into the navel orange tree, you would have the same thing you could theoretically get the other way, but way faster. So that is an example of GMO that makes total sense to me.

On the other hand, let's say you somehow make a GMO chicken that grows way faster, for increased commercial production, but has horrible quality of life. I think that would be really bad. And that is something that has already been done, but not with GMO, rather with old-fashioned selective breeding.

So it seems like the issue is not the tool, but rather the product of using the tool. In terms of whether it's natural or not, cyanide is natural, hospitals are man-made. Whether something is natural or man-made doesn't necessarily make it good or bad. That said, the natural equivalent to much of what's done with GMO is called "horizontal gene transfer." There are many examples of "horizontal gene transfer" in nature. Once such example is the human genome. There is stuff in our DNA that originally got there via horizontal transfer from one organism to another.

https://en.wikipedia.org/wiki/Horizontal_gene_transfer

[greg_D]

They have had GMO trees immune to greening for 10+ years. I think it was a spinach gene they spliced in back then. I don't want a GMO orange personally. The CUPS screen structures are working out great. We just can't afford to produce juice oranges in them. So, they will be for fresh fruit only (unless someone finds a cheap construction method). That means we will be saying good bye to ~90% of our citrus acreage sooner or later.  :'(

HLB was just detected in my city a month ago. I would be ok with GMO citrus as long as there are no health concerns ( is that what the issue is?). If there is a method to protect existing trees with injections prior to infection I would use it on my five trees.

I miss my Persian lime tree casualty of citrus green so I believe. As I sit here eating my GMO Corn Flakes I would be okay with a fortified citrus tree.

And people wonder why colon cancers are rising.

Cancer is caused when genetic mutations disrupt normal regulation of cell growth or inactivation of genes that control cell division and repair damaged dna (tumor suppressor genes). This can be caused by things that directly damage DNA, or things that increase cell turnover rate and thus increase the chance of a mutation happening. Inflammation does both. It promotes the creation of things that directly damaged DNA, and it increases cell turnover. To my understanding, obesity and unhealthy foods are both inflammatory. It stands to reason that those are probably more likely the cause of rising colon cancer rates as opposed to GMOs. To say it's GMOs you would need some sort of intermediate step where something being a GMO makes it more likely to do the things that result in cancer. Those things that cause cancer are specific and known. When we discover that something causes cancer it's because we discover that it does one of the things we already know causes cancer.

[chris03]

Personally, I dont think the long term solution is a GMO or the "peptide". What growers are doing now is injecting trees with oxytetracycline antibiotics. I doubt theres much residue in the fruit but I'm not sure. This may be new in citrus, but the apple and pear industries have been doing this for a while to my understanding. So to all those who are into the "no antibiotics ever" foods, maybe do some digging on that.
I think that the best solution is to breed a tolerant scion AND rootstock and the combination will be able to tolerate and produce through the disease. There are actually quite a few already released and seem very promising. Particularly the UFR series rootstocks I've got a few trees with very susceptible scions grafted onto UFR-17 in my yard under HEAVY disease pressure and they seem to do ok. I imagine if it was a more tolerant cultivar it would do much better, I actually started replacing with more tolerant scions.
I am also helping out with some research in my university we have some wild Australian species completely resistant to the bacteria AND they have an early flowering (precocious) gene. The f1, backcrosses, and f2 seem to be very promising, fruit is still relatively small and acid, but significantly larger than the parents species. This is definitely a more long term project focused on total resistance, but there is plenty of material that is ready and tolerant. Just my 2 cents.

[greg_D]

Personally, I dont think the long term solution is a GMO or the "peptide". What growers are doing now is injecting trees with oxytetracycline antibiotics. I doubt theres much residue in the fruit but I'm not sure. This may be new in citrus, but the apple and pear industries have been doing this for a while to my understanding. So to all those who are into the "no antibiotics ever" foods, maybe do some digging on that.
I think that the best solution is to breed a tolerant scion AND rootstock and the combination will be able to tolerate and produce through the disease. There are actually quite a few already released and seem very promising. Particularly the UFR series rootstocks I've got a few trees with very susceptible scions grafted onto UFR-17 in my yard under HEAVY disease pressure and they seem to do ok. I imagine if it was a more tolerant cultivar it would do much better, I actually started replacing with more tolerant scions.
I am also helping out with some research in my university we have some wild Australian species completely resistant to the bacteria AND they have an early flowering (precocious) gene. The f1, backcrosses, and f2 seem to be very promising, fruit is still relatively small and acid, but significantly larger than the parents species. This is definitely a more long term project focused on total resistance, but there is plenty of material that is ready and tolerant. Just my 2 cents.

There's someone named "Herbalistics" on Facebook and Instagram that has some interesting Australian hybrids. They look fascinating to me as someone unfamiliar with them.

A peptide is a short chain of amino acids. A protein is a long chain of amino acids; technically, a protein is a polypeptide made of multiple peptides linked together.

This specific 'peptide,' this molecule, is naturally in finger limes. Which means people have been eating it for hundreds of years with no ill effects. That said, despite being harmless to people, it basically pops the bacteria that causes citrus greening. Like a needle popping a water balloon. That's likely why finger limes are so resistant to HLB. If you extract this peptide from the finger limes, or recreate it in a lab, then get it into the circulatory system of another tree, it does the same thing (kill the HLB bacteria).

How do you get it into the circulatory system of the tree? Apparently, one way is to just spray it on.

More here: https://news.ucr.edu/articles/2021/02/08/researchers-find-peptide-treats-prevents-killer-citrus-disease

The presentation I heard about regarding this was exploring an injection into the tree. It makes me wonder if multiple companies are racing each other to bring a peptide-based cure to market. It's a naturally occurring product so it's not like it can be patented.

The hybridization stuff sounds cool, that said for people who want to grow existing varieties, instead of waiting for tolerance to be bred into those varieties, I think a foliar spray (if effective) that uses something naturally occurring in another citrus fruit as its active ingredient will be a real winner for home growers.

[soulsurfereverafter]

Nice...looking forward to growing a Tahitian pomelo in LA County....Im just a smooth brain gardener and I'll leave the science stuff to the smart people who have studied years and years to earn their credentials. 

[Seanny]

You all can graft fingerlime or Australian Desert Lime to your citrus tree so the graft nurses the tree. Just keep a short branch growing .

I’ve grafted fingerlime to my trees.
I’m waiting on them to push.
ADL is better but I can’t get ADL shipped here.

[CrowdedTown]

We said goodbye to our citrus years ago as they all slowly died.
I would not plant this since it would also kill orange dog caterpillars so it would doom any swallowtails that laid eggs on them

[nofspeppers]

[/quote]

There's someone named "Herbalistics" on Facebook and Instagram that has some interesting Australian hybrids. They look fascinating to me as someone unfamiliar with them.

[/quote]

I love seeing their hybrids on instagram. They have some great looking stuff.

[1rainman]

Cant be any worse than all the insecticides they use commercially but I wouldnt want it for a backyard tree. I would like a fingerlime crossed with a tangelo or something. Maybe an f2 or f3 of good quality that I can grow in a large pot.