Canker in Texas

[mrtexas]

I've been quizzing the Texas citrus experts about the canker and greening
quarantines in Texas. I am in Fort Bend County which is quarantined for
both. I am not in a canker area. I asked a lot of questions about moving trees,
seeds, and fruit into and out of the quarantine area. Harris County (Houston) is in the
same situation and is the next county north. They have found exactly one nursery
tree with greening. They found canker at a tree nursery but not at the tree
nurseries growers.

I found out I can graft my own tree but not a friend's tree. That is news to me
and I think the experts haven't spread the word very well about that. Many members of
the Facebook group graft trees. The local citrus tree growers are putting in screen houses,
even the ones outside the quarantine area.

What shocked me the most is that canker must have been here for some time.
Surely from people bringing in trees illegally from Florida. There have been 645 trees IDed with
canker and only 350 taken out. The canker area is about 5 miles from my back yard.
This is from someone directly involved in the quarantine.

I think long term only GMO will solve this problem.

Just looked it up. Sugar Land Dave who sometimes posts here is in the canker quarantine area!
I was at his house this spring to get budwood for his giant kishu bud sport that made fruit the size of satsumas
but turns out someone yanked that branch off his tree. Didn't know he was quarantined at the time either!

[luak]

Mark, i hope you find a way to protect your beautiful variety of fruit tree's,i know you sure put a lot of work there, good luck!

[mrtexas]

"I'm going to wade into this one. As a First Detector Specialist, I have been working with the A&M Plant Pathology Lab for three years now on Citrus Canker so I do have some information to share. The quarantine areas are set by the TDA through a court order. The Citrus Greening was set up per county lines. Citrus Greening is considered cautious but to date there have been NO in-ground trees testing positive for Greening. One can bring citrus into the three county quarantine if it is certified from a HLB-free facility. You are allowed to move citrus around inside the three counties. The Citrus Canker is very serious because it is Strain A, the most widespread and severe form of the disease. The strain in Rancho Viejo is a different and only attacks lemons and limes. The quarantine area for Citrus Canker is set up per square mile. The area has increased in size three times since July 28th and is set to be increased again in two weeks. The purpose of the quarantine is to eradicate the bacterium. TDA and USDA are canvassing the homeowners,testing trees and trying to remove them. This is a huge task since each tree is removed by persons completely suited, the trees are cut and bagged to be hauled off then the area is drenched. There are (to date) 645 positive trees just in Fort Bend. Harris has 33. Of the 645 trees, only 350 have been destroyed. Legally, they can only take positive testing trees but if a homeowner refuses destruction a court order is obtained to take it our. It is important that no citrus or citrus parts are moved into the area because of the possibility of re-infection. Also important no citrus or citrus parts leave the area since the bacterium can live on twigs, fruit, leaves...any part. As for preventative, A&M suggests owners use approved insecticides to minimize common insect damage since leafminer galleries are the most common avenue of infection. Preventive bactericides common for citrus are copper products. Look for neutralized copper sulfate or copper hydroxide products. Each must be labeled for citrus."

[LaCasaVerde]

" leafminer galleries are the most common avenue of infection. Preventive bactericides common for citrus are copper products. Look for neutralized copper sulfate or copper hydroxide products. Each must be labeled for citrus."

mrtexas how large of a collection do you have- outdoors?  Being so close Id have  a set protocol in place to minimize transmission to your citrus.

 

[LaCasaVerde]

here citrus canker was discovered in 2014, strain not known at the time but infected all citrus. It was then that I focused on an effective program on my citrus to protect  against this threat.  The canker was found 15 miles or so from my area.  I developed CCSD (citrus canker stress disorder)
here is what Ive been doing. Of course there a side effects but overall it has worked.

Protection methods Ive employed  for canker (and greening)
-Built a 28x14 greenhouse over the ones I wanted to make sure I saved in event of spread into my citrus. The greenhouse has roll up sides with insect netting to prevent the little white moths (citrus leaf miner adults) from entering this area. 

Those not protected totaling 25, I have the followed protocol followed religiously-(this is not a recommendation- it s what i do and is a product of my understanding of the listed chemicals- use your own due dilligence.)

-No pruning, grafting period during months March-December
-No weed eating around any tree base.
-Other than rain and foliar applications keep any and all excess moisture away from the plant - in particular the leaves.
-Copper sprays 3/4 times a year to protect against leaf leasions allowing the bacteria to enter. I used to do this once only in the spring...not anymore
- Soil drench with  Imidicloprid 24 percent every month april    through   /nov after  bloom
-Every flush after bloom I foliar spray  with miticide or  Imidicloprid  as new growth easily outgrows systemic protection and is first attacked
-Contact insecticide sprayed on the leaves every 2-3 weeks.

Im looking now for the longest residual kick back topical insecticide formulation as Malathion,sevin and all those tend to be washed off and ineffective after 5-7 days. Until then  I use Malathion . This is the first defense. Could use any advice or recommendations here....

side effects- explosive mite problems.
(correction for this is easier than the canker though)

mrtexas - you are correct . gmos will be the only solution barring  the development of an injectible/foliar applied/root uptake  systemic targeted bactericide

 






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[LaCasaVerde]

 ...lastly for those wondering why leaf miners are dangerous in tandem with this disease:

Leafminer Interaction: The Asian leafminer (Phyllocnistis citrella) can infest leaves, stems, and fruit and greatly increase the number of individual lesions which quickly coalesce and form large irregular shaped lesions that follow the outlines of the feeding galleries (Figure 11). Leafminers feed on the epidermis just below the leaf cuticle. Numerous cracks occur in the cuticle covering leafminer galleries providing means for bacteria to penetrate directly into the palisade parenchyma and spongy mesophyll which are highly susceptible to infection. Citrus foliar wounds normally callus within 1-2 days, however, the extensive wounds composed of the entire leafminer feeding galleries do not callus for 10-12 days, greatly extending the period of susceptibility of galleries to infection. Leafminer infestations can be very prevalent and severe producing hundreds if not thousands of potential infection courts on individual trees. When bacterial dispersal events occur in the presence of the leafminer, not only is inoculum production greatly exacerbated, but so is the potential for infection over the entire dispersal range.