Mango Pests, Diseases, and Nutritional Problems

[Guanabanus]

Mango Bacterial Black Spot.  Spray with Copper to reduce spread of MBBS.

[MANGOSCOPE]

Mango Bacterial Black Spot.  Spray with Copper to reduce spread of MBBS.

To reduce Mango BBS with copper, one may need frequent applications. Before, going through the process one should ascertain their current micronutrient analysis specially "Copper". Foliar spray shows little more promising in Alkaline soil than the banding/side dressing or brodcasting. copper toxicity in plants causing symptoms such as chlorosis and necrosis, stunting, leaf discoloration, and inhibition of root growth.
Copper impedes lignin synthesis in Toxic level which in turn interferes the process of photosynthesis, essential for plant respiration thus plant metabolism of carbohydrates and proteins are depleted.
To reduce spread or to contain to some extent we can spray Copper Oxychloride or Copper Oxide in a recommended doses.

KNOWING MANGO BACTERIAL BLACK SPOT IN FLORIDA:

https://edis.ifas.ufl.edu/publication/HS1369


ASSESSING COPPER THRESHOLDS FOR
PHYTOTOXICITY AND POTENTIAL DIETARY
TOXICITY IN SELECTED VEGETABLE CROPS:

https://irrec.ifas.ufl.edu/irsws/History%20Publications/1/JESHYang2002.pdf

[JakeFruit]

My 1 yr old Neelam graft on Kent rootstock hasn't been doing great, at all. It's getting the same fertilizer regimen as several other seedlings, all others doing fine.
It's had two flushes this season, but the leaves are up-turned and the trunk is thin, spindly-looking. The graft union isn't great, but seems well-healed. The rootstock has black pocks all over it (interestingly, none on the scion); guessing that's MBBS, but I also had a bad problem with anthracnose when we were getting rains nearly every day for the last two months. Maybe it's scion/rootstock incompatibility, but I'm thinking it's something wrong with the rootstock.


Does it look salvageable? I'm hoping to see some swelling buds before the grafting season is over, I'd feel better grafting onto another rootstock. It seems completely stalled/stunted at this point. Maybe I should hit it with fish fertilizer every week or so to see if that kicks it into gear.

[Guanabanus]

If the spots on the trunk are depressed, they are likely anthracnose;  if the spots are raised, they are likely Mango Bacterial Black Spot.

Copper sprays can fight the further spread of either disease.  Potassium Silicate spray can toughen the surface.

[JakeFruit]

Thanks Har. The centers of the spots are all definitely sunken, the edge/rim around the sunken spots are slightly raised, though. A few of the spots also have a slight yellow halo. The more I look at the state of the rootstock, the more I want to get a Neelam scion off it asap.

Any recommendations on forcing it to push new growth? It's getting a monthly time-released fertilizer with micros.
Would girdling the trunk 6" or so below the top do anything?

[mangoba]

If the dark spot on the graft union upper right bevel is sap, I wouldn't wait!

[mattyboydesigns]

Mango Bacterial Black Spot.  Spray with Copper to reduce spread of MBBS.

Thank you

[Tony714]

Hi,
I bought this Lemon Zest from parking lot sale.  It looks like graft on Manila rootstock.   I bought it late Apr but leaves like this.  Can you please let me know what may be and how to fix it?  I
I appreciate it.

Soil - perlite,  sand, potting soil
Sprayed Organocide

[Guanabanus]

Potassium deficiency, and other deficiencies.  Also may have been exposed to urea, which mangos mostly don't like.

Last couple of photos seem to show the leaf form of MBBS.

[MANGOSCOPE]

Thanks Har. The centers of the spots are all definitely sunken, the edge/rim around the sunken spots are slightly raised, though. A few of the spots also have a slight yellow halo. The more I look at the state of the rootstock, the more I want to get a Neelam scion off it asap.

Any recommendations on forcing it to push new growth? It's getting a monthly time-released fertilizer with micros.
Would girdling the trunk 6" or so below the top do anything?

Going back to Basics: To regulate plants normal vigor.
==============================================

1) Sunlight: Needs 6-8 hours of Sunlight

2) Watering: Frequent watering kills more mango trees than less watering. Rely more on rain water than sprinkler or other irrigation systems unless, there is a serous drought going on. For established mango trees watering isn't required.

3) Fertilizers: Try to go with 10-10-10(having  primary and secondary macronutrients with micro) to boost vegetative growth, root growth and overall plant health and vigor,1-2 months apart, in a recommended dose. If you have been using 8-3-9, stop that for few months. 

4) Pesticides: Use it, depending on the disease condition.

5)Soil condition: Test soil ph and correct it if it is adverse for the growth. Mangoes do like little alkaline soil.

[JakeFruit]

1) Sunlight: Needs 6-8 hours of Sunlight

2) Watering: Frequent watering kills more mango trees than less watering. Rely more on rain water than sprinkler or other irrigation systems unless, there is a serous drought going on. For established mango trees watering isn't required.

3) Fertilizers: Try to go with 10-10-10(having  primary and secondary macronutrients with micro) to boost vegetative growth, root growth and overall plant health and vigor,1-2 months apart, in a recommended dose. If you have been using 8-3-9, stop that for few months. 

4) Pesticides: Use it, depending on the disease condition.

5)Soil condition: Test soil ph and correct it if it is adverse for the growth. Mangoes do like little alkaline soil.

Thanks for the suggestions! I am using a soilless mix with pine bark fines. I thought mangos preferred slightly acidic soils, but tolerate slight variance on either side of neutral.
I should get a good 10-10-10 for use with seedlings. I don't think my 8-3-9 with micros feeds the young ones enough.

As luck would have it, the Neelam is just starting to push again as of this morning; looks like I will get a scion off of it.

[MANGOSCOPE]

No problem Jakefruit. You're welcome.
If you use solely Pine bark, the ph of which is slightly acidic for mangoes around 4.0 -5.0. And of course, lot of fruit trees love that like Lychees. So, you may consider increasing the ph a bit around 6.0-6.5. By adding lime,  probably, it will solve the ph issue though...

[mangoba]

This year my unknown mango tree has some yellow patch in the middle.
It only shows on old leaves, the new young leaves look normal. This tree is about 3 years old, 2nd year in the ground. About 6 ft tall.
Is it lack of nitrogen? Or too much water?
Other Zill varieties grafted are doing well.
They all get the same fertilizer and same watering schedule.

Thanks everyone!

Just read this today and thought of you.

[mangoba]

Har and Mark,

I always bring the brain teaser questions.

So I have few 1 year old mango seedlings in ground that showed at some point Phosphorus deficiency (8.4 pH/leaching sandy soil/ 90% Calcium). So for the last 5 weeks, I have been giving 2 Tbsp of 18-18-18 and that helped them tremendously. The seedling that had showed the least deficiency is now showing what appears to be a toxicity as described in this paragraph.

Mango trees appear to be quite sensitive to heavy phosphorus fertilization accumulating as much as 0.84 per cent phosphorus in leaves on dry weight basis against 0.08 – 0.175 per cent in normal leaves. This excessive phosphorus resulted in a spotting of mature leaves in fall, first appearing on the lower surface, but later on also on the upper surface.

Necrotic areas also developed on the margins of some leaves. Leaves become chlorotic and shed heavily. It also causes some drying of shoots.

How would you deal with this problem please? I have Potassium Nitrate for next week fertilizer dose and I also have Calcium Nitrate. Can I give some calcium to lock up some Phosphorus?

Thanks

Edit: One week I remembered that I skipped 18-18-18 but gave about 75gr of DAP and 75gr of Potassium Nitrate 
Edit: Just gave 20gr of Sequestrene and 15gr of EDTA chelated mix with 0.6% Zinc.
Edit: Added an image, after cleaning all the older leaves that dried up and died already.




 

[Mark in Texas]

Har and Mark,

I always bring the brain teaser questions.

So I have few 1 year old mango seedlings in ground that showed at some point Phosphorus deficiency (8.4 pH/leaching sandy soil/ 90% Calcium). So for the last 5 weeks, I have been giving 2 Tbsp of 18-18-18 and that helped them tremendously. The seedling that had showed the least deficiency is now showing what appears to be a toxicity as described in this paragraph.

You sure don't need any more Ca. Saltpeter (14-0-43) might be a good food but your faves still need micros.  Contrary to Fl. growers I push my young mangos with a moderate to high N food.  Osmocote Indoor/Outdoor Plus would be good choice for your younguns.

I gave up the high P teat long ago.  Most of my foods are low P like a Peters 25-5-15.  Also high P foods contribute to long internodes, legginess.  Most blame it on too much N.  Not so.

[mangoba]

I gave up the high P teat long ago.  Most of my foods are low P like a Peters 25-5-15.  Also high P foods contribute to long internodes, legginess.  Most blame it on too much N.  Not so.

Thanks Mark, but do you think a low P will work for me with that kind of pH and 90% calcium. I'm still currently at the stage of getting seedlings established.

[Mark in Texas]

I gave up the high P teat long ago.  Most of my foods are low P like a Peters 25-5-15.  Also high P foods contribute to long internodes, legginess.  Most blame it on too much N.  Not so.

Thanks Mark, but do you think a low P will work for me with that kind of pH and 90% calcium. I'm still currently at the stage of getting seedlings established.

High P foods can induce micros deficiencies.  Seedlings need plenty of N, not P.

[CarloGolfer]

Lots of flies and eggs. Are these bad? Nothing to worry about? This is my Glenn mango. It seems to be frozen in time. It appeared to be about to put out a big flush, but the little nubs have been the same for at least a month
 Meanwhile all my other trees are pushing like crazy and have no flies.

[Guanabanus]

Probably mango-scale eggs.   

[Mark in Texas]

Agree with Har, those look like eggs.  Hard to beat a thorough spray of Bonide All Seasons Hort. oil.  If I have a pest like mealybugs (which I did) I add 1 tsp/gal. of Bifen to it.  For the organic purists bifenthrin and permethrin and their sista products are about as non toxic to animals as it gets.  However they'll knock down a big yellow grasshopper within a minute.

[CarloGolfer]

Thanks for the advice. I'll grab the product on my way home. Have a nice evening!

[mangoba]

I'm confused. Does this look like a disease or a nutritional issue please.

[mangoba]

What do you think about this combo please. (EDTA Micros)


N-   P-    K-   Mg-  S-  Z-    Mn
17- 12-  12-  3.8- 13- 0.3- 0.2

[Guanabanus]

If the soil isn't already high in Ca, B, and Fe, you will also need to add those.

[Guanabanus]

Those leaves probably have a total-salts burn;  however, they could have some kind of powdery mildew.