Bactericide and fungicide for trees

[stubuzz]

I have several Mango trees in that garden that are in poor health and oozing brown gunge.  I i have fertilized then and i would like to give them a spray to kill any bacteria or fungus that is present. Can anybody recommend a good product?

[soidog2]

You should post some pictures of the " oozing brown gunge " too vague for useful help.

[Thian]

Spray neem-oil (nam sadao) or wood vinegar....or seaweed extract or multi-micronutrients, or molasses...

 

But the oozing i  also have and don't know what it is. And i sprayed all above.

[cooked]

I'm wondering why you suspect bacteria or fungus? If it IS a bacteria you won't be able to  do much about it.

Insect attack can lead to sap oozing from the leaves and fruits, which in its turn becomes infected by various fungi. The excrement of aphids will also attract fungi.

Another source of 'gunge' can be incorrect pruning or pruning at the wrong time of the year. 

Too much nitrogen is not good for fruiting mangoes, maybe .... ?

 

[drtreelove]

Cooked's suggestions/ observations are excellent points. 

 

If the oozing that you are witnessing is on the woody stems: Mango trees are susceptible to borer activity, beetles that invade the woody stems. The entry site will ooze the substance that you describe. Although some beetle borers in other situations can form galleries that cut off sap flow, or introduce fungi that block circulation, these mango borers do not appear to be destructive in this way with a minor infestation, just unsightly.  Heavy activity could prove me wrong and cause impaired sap flow or weakening of structural integrity. 

 

There is no insecticide, fungicide or bactericide that will stop the infestation or resulting infection after the fact. With exception maybe of a highly mobile systemic chemistry that may get to the active feeders, but may also translocate into the fruit.

 

Preventive spraying is the only way; an insecticide barrier with substantial residual effectiveness can be sprayed on the tree trunk and scaffold limbs.  US arborists call it "bark banding" or "trunk banding" treatment and it is used successfully to prevent the very serious killer infestations of pine bark beetles and oak bark beetles and others. The chemical pesticides of choice are pyrethroids mixed at the highest label rate of concentration in order to get the most residual effect: permethrin with about 3 - 4 months residual, or bifenthrin with up to a year residual.  

 

The organic program compatible alternative would be to

• do nothing observe for level of activity and any harmful effects and let biological controls, natural pest predators do their thing. Weaver ants love mango trees and they are an important biological control as aggressive predators. 
• botanical sprays for banding, like wood vinegar, neem products, rosemary or clove oil or others will be very short lived as far as residual effectiveness. You would need to spray at least every one or two weeks to keep the concentration up. Most people find this to be too time consuming and expensive. 

Water management, irrigation and mulching to preserve soil moisture is important. Most beetle infestations are predisposed by drought stress. 

 

The decline in tree health may not be related to the borers as much as to other factors, soil fertility and water management. Chemical fertilization only covers a small range of plant nutrient needs. Most over the counter fertilizers don't provide Calcium, Boron, Iron, Copper and other elements that are important for plant nutrition and resistance to pests and diseases. Improving your soil, preferably with soil testing and prescription mineral and biological amendments is important. But you can get a lot of slow release nutrition with incorporation of organic matter, use of manures and mulching. 

[JungleBiker]

I am not recommending you apply antibiotics but just want to point out that in Thailand some farmers are using antibiotics to treat citrus trees infected with citrus greening disease. Apparently it works but I do not recommend this practice. 

[Thian]

https://plantvillage.org/posts/5056-plantvillage-request-the-support-for-mango

[CLW]

Cooked's suggestions/ observations are excellent points. 
 
If the oozing that you are witnessing is on the woody stems: Mango trees are susceptible to borer activity, beetles that invade the woody stems. The entry site will ooze the substance that you describe. Although some beetle borers in other situations can form galleries that cut off sap flow, or introduce fungi that block circulation, these mango borers do not appear to be destructive in this way with a minor infestation, just unsightly.  Heavy activity could prove me wrong and cause impaired sap flow or weakening of structural integrity. 
 
There is no insecticide, fungicide or bactericide that will stop the infestation or resulting infection after the fact. With exception maybe of a highly mobile systemic chemistry that may get to the active feeders, but may also translocate into the fruit.
 
Preventive spraying is the only way; an insecticide barrier with substantial residual effectiveness can be sprayed on the tree trunk and scaffold limbs.  US arborists call it "bark banding" or "trunk banding" treatment and it is used successfully to prevent the very serious killer infestations of pine bark beetles and oak bark beetles and others. The chemical pesticides of choice are pyrethroids mixed at the highest label rate of concentration in order to get the most residual effect: permethrin with about 3 - 4 months residual, or bifenthrin with up to a year residual.  
 
The organic program compatible alternative would be to

• do nothing observe for level of activity and any harmful effects and let biological controls, natural pest predators do their thing. Weaver ants love mango trees and they are an important biological control as aggressive predators. 
• botanical sprays for banding, like wood vinegar, neem products, rosemary or clove oil or others will be very short lived as far as residual effectiveness. You would need to spray at least every one or two weeks to keep the concentration up. Most people find this to be too time consuming and expensive. 

Water management, irrigation and mulching to preserve soil moisture is important. Most beetle infestations are predisposed by drought stress. 
 
The decline in tree health may not be related to the borers as much as to other factors, soil fertility and water management. Chemical fertilization only covers a small range of plant nutrient needs. Most over the counter fertilizers don't provide Calcium, Boron, Iron, Copper and other elements that are important for plant nutrition and resistance to pests and diseases. Improving your soil, preferably with soil testing and prescription mineral and biological amendments is important. But you can get a lot of slow release nutrition with incorporation of organic matter, use of manures and mulching. 

Is something like this effective and available in Thailand?

[drtreelove]

8 hours ago, CLW said:

I don't know, but that is the tanglefoot principal, a narrow band that may stop ants and other pests from traveling up and down the stem.  But it would not stop flying insects like bark beetles from alighting and entering the stem wood at other points along the trunk.  The chemical trunk banding treatment that I was mentioning would need to be sprayed on a larger surface area. 

On 1/23/2018 at 1:00 PM, JungleBiker said:

 

[CLW]

Okay, thank you.
It's clear now

[drtreelove]

On 1/23/2018 at 1:00 PM, JungleBiker said:

I am not recommending you apply antibiotics but just want to point out that in Thailand some farmers are using antibiotics to treat citrus trees infected with citrus greening disease. Apparently it works but I do not recommend this practice. 

This is an interesting point. I don't know what Thai citrus growers are using or how they are applying, but the use of antibiotics for tree disease needs some clarification of material and method of application depending on the disease and how it is transmitted. Different diseases enter the tree in different ways. Fireblight is a bacterial disease that enters through the flowers, so repeated spraying an antibiotic during bloom as a preventive barrier is sometimes effective. 

 

The HLB bacteria/ citrus greening disease is introduced by an insect vector, a psyllid that is a sucking insect which inserts it mouth parts and in so doing introduces the bacterial disease. So the bacteria is never present on the plants external surface and therefore can not be contacted and controlled with an external spray. Stem injection of antibiotics is possible, but that is an expensive late response to an active infection.  It is far better in my opinion, to prevent the infection from taking place in the first place by preventive repellent protection from the insect vector. 

 

Some bark beetles introduce fungi when they bore into the tree trunk. Preventing the borer activity with a barrier treatment is much more practical and effective than trying to control the active fungal infection.  

[CLW]

This is an interesting point. I don't know what Thai citrus growers are using or how they are applying, but the use of antibiotics for tree disease needs some clarification of material and method of application depending on the disease and how it is transmitted. Different diseases enter the tree in different ways. Fireblight is a bacterial disease that enters through the flowers, so repeated spraying an antibiotic during bloom as a preventive barrier is sometimes effective. 
 
The HLB bacteria/ citrus greening disease is introduced by an insect vector, a psyllid that is a sucking insect which inserts it mouth parts and in so doing introduces the bacterial disease. So the bacteria is never present on the plants external surface and therefore can not be contacted and controlled with an external spray. Stem injection of antibiotics is possible, but that is an expensive late response to an active infection.  It is far better in my opinion, to prevent the infection from taking place in the first place by preventive repellent protection from the insect vector. 
 
Some bark beetles introduce fungi when they bore into the tree trunk. Preventing the borer activity with a barrier treatment is much more practical and effective than trying to control the active fungal infection.  

October issue of Home Agricultural Magazine (Kehakaset) had a big article about the extinction of citrus greening in North of Thailand by antibiotics stem injection. So it seems common practice here...
Not to mention the residues and build up of resistance by doing this.

[drtreelove]

8 hours ago, CLW said:

October issue of Home Agricultural Magazine (Kehakaset) had a big article about the extinction of citrus greening in North of Thailand by antibiotics stem injection. So it seems common practice here...
Not to mention the residues and build up of resistance by doing this.

Is it a Thai language article?  Do they state what antibiotic is being used and what type of injection equipment?  Could you post or email me a link? my username at gee mail

 

This paper is more than most of us need to know, but an example of a thorough study of control measures for the insect vector and the pathogen.

 

http://www.imok.ufl.edu/hlb/database/pdf/12_Boina_14.pdf

 

3.1 Trunk-applied/injectedantibioticsandbudwood/root soakinginantibioticsolution Among the few management options available for temporary cure of the HLB disease (controlling the disease and/or reducing the severity of symptoms), the use of antibiotics is receiving renewed interest. Antibiotics are administered either by trunk injection113–115 or by dipping/soaking of budwood or plant roots inantibioticsolution.112,116–119 Budwoodimmersedintetracycline (1000.0 mg L−1 for 2 h or 500.0 mg L−1 for 3 h) solution yielded good results.118 Tetracycline hydrochloride is the most commercially applied therapeutic treatment for HLB control. This antibiotic is not bactericidal but bacteriostatic, necessitating frequent
PestManagSci(2015) ©2014SocietyofChemicalIndustry wileyonlinelibrary.com/journal/ps
www.soci.org DRBoina,JRBloomquist
applicationsatregularintervals(annualbasis)forcontinuoussuppression of HLB pathogen.113 The frequent application of tetracycline makes it less cost effective and increases the chances of the pathogen becoming antibiotic resistant.113 In addition, repeated trunkinjectionsoftetracyclineledtophytoxicityininjectedcitrus trees.113,115 Althoughbothmethodsoftreatment(trunkinjectionsandbudwoodsoaking)withtetracyclineresultedintemporaryreliefofHLB symptoms (1.0–1.5 years),113,115,118,119 trunk injections provided the best results in Taiwan, China, Reunion, the Philippines, South Africa and India.113,115 One report claimed budwood treated by dipping in 500.0 mg L−1 of ledermycin/penicillin combined with 500.0 mg L−1 of carbendazim for 1 h resulted in complete controlofHLBdisease.119 Whentestedindifferentseasons,treetrunks injected with antibiotics during spring season provided the best results.115 

[stubuzz]

Here is one of the trees.

I have noticed another is covered in sooty mold and tree hoppers. I have sprayed with wood vinegar, but they are still there. Ant tips?

[CLW]

Is it a Thai language article?  Do they state what antibiotic is being used and what type of injection equipment?  Could you post or email me a link? my username at gee mail
 
This paper is more than most of us need to know, but an example of a thorough study of control measures for the insect vector and the pathogen.
 
http://www.imok.ufl.edu/hlb/database/pdf/12_Boina_14.pdf
 
3.1 Trunk-applied/injectedantibioticsandbudwood/root soakinginantibioticsolution Among the few management options available for temporary cure of the HLB disease (controlling the disease and/or reducing the severity of symptoms), the use of antibiotics is receiving renewed interest. Antibiotics are administered either by trunk injection113–115 or by dipping/soaking of budwood or plant roots inantibioticsolution.112,116–119 Budwoodimmersedintetracycline (1000.0 mg L−1 for 2 h or 500.0 mg L−1 for 3 h) solution yielded good results.118 Tetracycline hydrochloride is the most commercially applied therapeutic treatment for HLB control. This antibiotic is not bactericidal but bacteriostatic, necessitating frequent
PestManagSci(2015) [emoji767]2014SocietyofChemicalIndustry wileyonlinelibrary.com/journal/ps
www.soci.org DRBoina,JRBloomquist
applicationsatregularintervals(annualbasis)forcontinuoussuppression of HLB pathogen.113 The frequent application of tetracycline makes it less cost effective and increases the chances of the pathogen becoming antibiotic resistant.113 In addition, repeated trunkinjectionsoftetracyclineledtophytoxicityininjectedcitrus trees.113,115 Althoughbothmethodsoftreatment(trunkinjectionsandbudwoodsoaking)withtetracyclineresultedintemporaryreliefofHLB symptoms (1.0–1.5 years),113,115,118,119 trunk injections provided the best results in Taiwan, China, Reunion, the Philippines, South Africa and India.113,115 One report claimed budwood treated by dipping in 500.0 mg L−1 of ledermycin/penicillin combined with 500.0 mg L−1 of carbendazim for 1 h resulted in complete controlofHLBdisease.119 Whentestedindifferentseasons,treetrunks injected with antibiotics during spring season provided the best results.115 

The article is in Thai. Only a small abstract in English.
The name of the chemicals is obviously transliterated to Thai as I couldn't read it in the article.

[drtreelove]

4 hours ago, CLW said:

The article is in Thai. Only a small abstract in English.
The name of the chemicals is obviously transliterated to Thai as I couldn't read it in the article.

Thanks, I'm going to work on getting more information on this.  

But I have had quite a bit of experience with tree stem injection technology and the systemic chemistries used, and I have my doubts that antibiotic injection can be a viable solution to control of HLB, that it is acceptable for a food plant, and even if it was, that it could be sustained as an annual treatment without serious drawbacks; namely injection site tissue necrosis compounding with repeated drilling and plugging, and then there is the cost of repeated treatments. It is definitely not organic program compatible and in the USA systemic antibiotic injection is restricted to non-food plants, organic or not. 

 

The state of the science choice for an injectable systemic antibiotic now in the US is ArborJet's highly researched and effective product ArborOTC, label attached, which clearly states non-food bearing plants only.  I'm not sure that you want it in your orange juice. 

 

Arbor-OTC™ is a systemic water soluble injectable
antibiotic for the annual suppression of bacterial diseases
in non-food bearing palms including Phytoplasma Disease
(Lethal Yellowing and Texas Phoenix Palm Decline). It can
also be used for the control of bacterial diseases in nonfood
bearing trees including Bacterial Leaf Scorch.
Ingredients:
Oxytetracycline Hydrochloride*....................................... 39.60%
Other Ingredients....................................................................................60.40%
Total.............................................................................................................100.00%

 

And then there is this from the previous article I posted: 

 

"The frequent application of tetracycline makes it less cost effective and increases the chances of the pathogen becoming antibiotic resistant. In addition, repeated trunk injections of tetracycline led to phytoxicity in injected citrus trees."

 

So back to the original post, I'm with Cooked:  "If it IS a bacteria you won't be able to  do much about it." 

Unless maybe you have deep pockets for an expensive treatment program, or what I would suggest: work to prevent further infections by pro-actively controlling the insect vector. Which is often possible with an organic program.  

 

 

 

Arbor_OTC_1_07.pdf

[drtreelove]

One of my daughters, a biologist in Chiang Mai, contacted someone associated with the article and program. He stated that most citrus growers in this program using antibiotic as a curative are using ampicillin. 

 

It's interesting to note that this antibiotic has been researched as a soil/root drench or foliar spray, as well as trunk injection. 

 

Here's a paper from 2015 which is very informative about some of the research, but expresses my concern about suitability for food crops. Commercial producers probably don't care as long as they can get away with it and not lose their trees and crop. But it would not be organic program compatible as far as this information goes. I'll still keep trying to find out more.

 

https://www.omicsonline.org/open-access/application-of-antibiotics-for-control-of-citrus-huanglongbing-aaa-1000102.pdf

 

Beta-lactam antibiotics such as Ampicillin (Amp), and Penicillin (Pen), can inhibit the growth of sensitive bacteria by inactivating enzymes located in the bacterial cell membrane, known as penicillin binding proteins, which are involved in cell wall synthesis [7]. In our previous studies, it was reported that Amp or Pen can eliminate Las bacteria in HLB-affected periwinkle and citrus when applied via root drench, foliar spray, or trunk injection [8-10]. In graft-based assays, Amp and Pen also displayed the greatest antimicrobial activity against Las showing no phyto-toxicity on citrus [11]. In addition as a response to Amp and Pen treatments, the microbial community and structure within the citrus leaf, which is important factor in how Las affects HLB progression, was modified [12,13]. Furthermore, Amp and Pen is easily taken up by citrus [11,12]. Therefore, Amp and Pen have so far been shown to be the most effective antimicrobial compounds against Las. However, due to the public concerns on the emergence of antibiotic resistant bacteria and the potential side effect on human beings, application of ampicillin and penicillin has not yet been approved to be used on crops by the Environmental Protection Agency (EPA) or other regulatory agencies. It may be a considerable, optional strategy to use Amp or Pen as an emergency use agent for control of HLB.

 

So in other words, enjoy your orange juice, but watch out for flesh-eating, antibiotic resistant bacteria. 

[CLW]

One of my daughters, a biologist in Chiang Mai, contacted someone associated with the article and program. He stated that most citrus growers in this program using antibiotic as a curative are using ampicillin. 
 
It's interesting to note that this antibiotic has been researched as a soil/root drench or foliar spray, as well as trunk injection. 
 
Here's a paper from 2015 which is very informative about some of the research, but expresses my concern about suitability for food crops. Commercial producers probably don't care as long as they can get away with it and not lose their trees and crop. But it would not be organic program compatible as far as this information goes. I'll still keep trying to find out more.
 
https://www.omicsonline.org/open-access/application-of-antibiotics-for-control-of-citrus-huanglongbing-aaa-1000102.pdf
 
Beta-lactam antibiotics such as Ampicillin (Amp), and Penicillin (Pen), can inhibit the growth of sensitive bacteria by inactivating enzymes located in the bacterial cell membrane, known as penicillin binding proteins, which are involved in cell wall synthesis [7]. In our previous studies, it was reported that Amp or Pen can eliminate Las bacteria in HLB-affected periwinkle and citrus when applied via root drench, foliar spray, or trunk injection [8-10]. In graft-based assays, Amp and Pen also displayed the greatest antimicrobial activity against Las showing no phyto-toxicity on citrus [11]. In addition as a response to Amp and Pen treatments, the microbial community and structure within the citrus leaf, which is important factor in how Las affects HLB progression, was modified [12,13]. Furthermore, Amp and Pen is easily taken up by citrus [11,12]. Therefore, Amp and Pen have so far been shown to be the most effective antimicrobial compounds against Las. However, due to the public concerns on the emergence of antibiotic resistant bacteria and the potential side effect on human beings, application of ampicillin and penicillin has not yet been approved to be used on crops by the Environmental Protection Agency (EPA) or other regulatory agencies. It may be a considerable, optional strategy to use Amp or Pen as an emergency use agent for control of HLB.
 
So in other words, enjoy your orange juice, but watch out for flesh-eating, antibiotic resistant bacteria. 

That's why I stopped consuming orange products in Thailand. Lemon is not better I guess. Still enjoy fresh soda manao occasionally...