The MGS Forum
Gardening in mediterranean climates => Pests and diseases => Topic started by: hereistay on October 22, 2013, 11:54:48 PM
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Two weeks ago I bought 45 plants of Pistacia Terebinthus.
These have 2-4 years and are inside a 9x5 alveolar polystyrene tray.
The seller told me to put them outside and to humidify the soil.
I live in Center Italy, at the same latitude of Rome but on the Adriatic coast, at about 10km from the sea with an altitude od about 200m slm.
Here in Abruzzo Pistacia Terebinthus grows spontaneous on mountains, and at an altitude of about 600m slm.
These plants come from southern Italy where the temperaturea are higher than here but they have been cultured at 1000m slm, so the temperature is not a problem I think.
When the plants arrived, leaves were yellowing and there were black spots on leaves.
Now, after two weeks, a lot of leaves have dried and it doesn't seems to be due to fall season.
This is a deciduous plant, so it is normal loosing leaves at this time, but there are these spots and i want to understand what it is!
I can add that the first 10 days I put the plants inside a big agricultural greenhouse because temperatures seemed to have lowered and it was raining but this week temperatures raised so I asked the seller and I decided to put them outside.
What is strange, according to me, is that the seller told me to water twice a week, because I read that this plant suffers of root rot and can live on rocks without water for a long time!
So, by watching these photos, are you able to tell me what these spots are?
(http://img196.imageshack.us/img196/2702/61fg.jpg) (http://imageshack.us/photo/my-images/196/61fg.jpg/)
(http://img22.imageshack.us/img22/508/0qii.jpg) (http://imageshack.us/photo/my-images/22/0qii.jpg/)
(http://img811.imageshack.us/img811/9012/b8lo.jpg) (http://imageshack.us/photo/my-images/811/b8lo.jpg/)
(http://img854.imageshack.us/img854/3561/rawv.jpg) (http://imageshack.us/photo/my-images/854/rawv.jpg/)
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It looks very much like Septoria leaf spot.
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Septoria pistaciae commonly affects deciduous Pistacias around the Mediterranean and elsewhere. Trials in the 1990s in commercial pictachio orchards in Arizona found that common fungicides including Benlate did control the spotting, so much so in fact that while in untreated trees the leaves around nut clusters had died off by harvest those in treated trees were still alive. (But the trial plots were too small to show whether this improved the actual harvest yield.)
I doubt if it's worth bothering to spray your plants, unless you find the spotting really disfiguring.
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Ok...
So if it is Septoria, have I to remove leaves or to prune?
I would to spray cupric because I read that next spring the disease may occur again and my goal is to let them grow to graft with Pistacia Vera from next year, so I want vigorous plants.
Now I'm going to put about 30 plants inside phyto bags (the black plastic bags for plants) and I'll leave them there and I'll try to graft while they are inside bags.
I want to plant in orchard the remaining 25 plants and try to graft them in the coming years.
According to you have I to plant now or is better to wait next spring?
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Your questions are not straight forward. Frankly with this level of infestation I suggest that you ask your supplier for clean material. Is P. vera susceptible to disease? I would cut back as hard as you can to an obvious bud, collect all the clippings and fallen leaves and burn.
Move these plants to a clean area. Spray now with benlate, copper or any general fungicide and again in two weeks. Start to spray in the spring as soon as fresh growth appears.
Probably it is better to plant now..... assuming you have confidence that the shortened plants will establish and grow.Perhaps you should ask the supplier for his advice----after all he should be the expert.
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The supplier told me to plant now in orchard or to leave inside the polystirene tray until next spring!
Today I removed the dried leaves and tomorrow I'm going to put about 20 plants inside plant bags and to spray a cupric fungicide.
I'm going to spray cupric sulphate g.10 (=124 g/l) in a ratio of 16ml/l.
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Today I moved the plants to plant bags, now i have 20 plants in plant bags, 3 plants in pots and 22 plants in the polystirene tray, so they have more space than before!
About the treatment for Septoria, someone told me to use triazole fungicide, because a cupric one is ineffective, but someone told me if these plants will survive after this treatment because they are too little!
What do you think about it?A fungicide treatment will kill them?
I thought also to put some straw on the top of the bags to defend from cold, what do you think about it?It's a good idea?
In general it's a good idea to leave these plants outside?
Here some photos:
Plants in plant bags (23):
(http://img820.imageshack.us/img820/1931/yzax.jpg) (http://imageshack.us/photo/my-images/820/yzax.jpg/)
Plants in tray (22):
(http://img534.imageshack.us/img534/4083/4vhs.jpg) (http://imageshack.us/photo/my-images/534/4vhs.jpg/)
I placed the plants on a old house terrace south-facing, as you can see in the photo below.
Do you think is a good place?
Have I to build a shelter from rain?
(http://img834.imageshack.us/img834/7249/s8bc.jpg) (http://imageshack.us/photo/my-images/834/s8bc.jpg/)
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The literature is not very good however it seems that all the Pistacia spp are equally susceptible to Septoria. The modern fungicides based on strobulirins give the best control however most broadspectrum fungicides seem to work satistactorily. It really depends on what is available on the market. Two sprays in the 3 Quarter seem to give best control but clearly you need to find out the local recommendations.
triazoles will do a good job.
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Somenone told me that fungicides based on strobulirins doesn't work at low temperatures...
So you mean strobulirins works good from July to September?
Anyhow now I'm not going to spray any fungicide because the leaves are falling and the incoming low temperature should stop the fungus.
I'm going to spray some penconazole at new growth in february-march!
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Penconazole is a broad spectrum triazole. I think you should spray now to try to reduce the innoculum that is building up in your plastic house. Clean up the fallen leaves as well.
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Plastic house?
The plants are outside...
Anyhow, do you think that sprying fungicide will kill these little plants?
And...what ratio have I to prepare to spray?On the label there is no ml/l quantity for pistacia terebinthus of course!
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A spray now will not hurt your plants. I cannot tell you what dose to use unless know the concentration of the product. .
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I don't know if I can write the brand of the product...on the label is written:
Active Ingredient in 100g of product: 19g (200 g/litre) PENCONAZOLE in the form of an oil in water emulsion.
Also contains: 139 g/litre hydrocarbon liquids, 1,2-benzisothiazolin-3-one.
For the control of Powdery Mildew in Grapes, Cucurbits, Peas and Apples and
Blackspot in Apples and Pears.
I have a question.
In a italian gardening forum, some members told me not to give fungicide because leaves are falling and low temperatures will stop the fungus.
Is it a good idea?
If I avoid the leaves to touch the soil, next spring Septoria will reveal again?
Is it true that winter low temperatures will kill Septoria fungus?
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Is you product aliquid of powder?? Not clear
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It is liquid!
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I have checked the Syngenta label. If your product contains 100g of active ingredient per litre the rate of use is 25ml per 100litres. Or
2.5ml per 10 litres. Hope that helps.
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It is Topas 200ew of Syngenta.
The label on my bottle says it is 200g/litre of penconazole, not 100g/litre...
Anyhow, David, are you expert with pistacia?
According to you it's ok if I leave the plants outside during winter season?
How much water should I give during winter?
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If your product contains 200gl/ litre then you can cut the rate by half. I am not a Pistachia expert just using common sense after a career in the plant protection business.
How much water will depend on how wet the winter is! I doubt if you will need to water very often however.
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Ok!
Thank you very much!
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I have a little problem!
Here where I live it's raining from 10th November.
I have these plants outside, I tried to cover them but they passed a day and half under the rain.
Yesterday, when rain stopped for a while I made additional drainage holes in the part that rests on the ground of the plant bags and I put them on perforated plastic containers, to facilitate drainage.
In the last days there were temperature anomalies for this period (>20°C) but the plants were allmost without leaves but I don't know if because of Septoria or because of dormancy.
When I put plants inside plant bags I made a soil mixture with about 150lt of universal soil, 50lt of volvanic lapilli (large grain), 25lt of expanded clay, a large bucket of sand.
Some of the bags are with volcanic lapilli and some with clay.
Is it well-drained enough?
In the bottom I put clay or lapilli or stones but not in all the bags.
The plastic sheet seems to do its work, in fact the stems of the plants are not wet.
Now it is not raining but a lot of rain is arriving according to weather forecast so I don't know what to do, if to leave them where they are or to move, maybe in the greenhouse.
This is the current situation:
(http://img203.imageshack.us/img203/3774/2mkd.jpg) (http://imageshack.us/photo/my-images/203/2mkd.jpg/)
Sorry if I am over topic!
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Your soil mix sounds to me as if it has OK drainage. A very basic test is to pour water into the top of a plant pot. It should quickly drain away from the top. If water still stands in the top of the pot, you need more drainage.
Lifting the pots off the ground by using those plastic crates is a good idea. (Perhaps not if you expect hard frost though!)
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Hello everyone!
3 weeks ago my plants started to grow, but today I noticed the first spot of septoria! :/
So, I decided to give penconazole in the form of Topas 200 ew at 0.25ml/l.
Please tell me if my calculations are ok!
Topas 200ew has 200g/l of penconazole, so it means that every ml is 0.2g of penconazole, so 0.25ml has a total of 0.05g of penconazole.
I have now a product with 1,5g/l of penconazole, so it means that 1ml is 0.0015g of penconazole, so to have 0.05g I need of 33.333ml of the product.
So I need of 33.333ml in a liter of water to have the same 0.2ml/l with topas 200ew.
Is it correct?
ps: my perplexity is: why a ready-to-use fungicide has a so high concentration?
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Correct, calculation! I can only assume that the formulation you are using is the " commercial " formulation which makes measuring "easier" for the farmer?
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Today I sprayed penconazole!
A question, I made some graftings, one month ago, pistacia vera on my terebints, have I also to treat them with fungicide?
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In these days I read a lot of stuff and I found that septoria on pistacia is treated with:
-trifloxystrobin+tebuconazole
-25.2 % W/W Boscalid 12.8 % W/W Pyraclostrobin (is acommercial one)
-dithiocarbamates
-metconazole
-tebuconazole
-azoxystrobin
-chlorothalonil
-ciprodinil+fludioxonil
-propiconazole
-fluopyram+tubeconazole
According to you wich one is the best?
I used penconazole, but I know that all these other fungicides are used as prevention, not as cure.
So if the spots are on leaves already I have to spray a curative fungicides, is it?So for this year I'm going to spray penconazole.
Next year can I spray a better fungicide (one of the list), after the first leaves appear?
My goal is to graft these terebinths with pistacia vera, so I need healty plants!
So, according to you, how many years have I to treat them with fungicides to defeat pistoria?
Another question, I planted in field 10 of these plants, I treated them but is it possible that the fungus is in the ground plate?
If it is right, is it possible that the soil and plants near them will be infected?
How is it possible to defeat the fungus if it is in the soil?
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The strobilurins are a "recent" discovery. Gm for gm they are probably the most active of the fungicides. They have systemic, curative and protective properties with I think a fairly specific mode of action. The dithiocarbamates on the other hand are protective fungicides but with a broad mode of action and were around in the 60s ...if I remember correctly.
They are both good fungicides. It is a good idea to use them alternately to stop build up of resistance however I doubt if there is sufficient inncolum in your garden which might be selected for resistance!
I,m not sure how often you wil have to treat however in my experience with apple scab, mildew, vine diseases, coffee etc its non stop. I have not check the life history of Septoria on pistachia...however it should be very easy to check on the web. I do not think it comes " from the soil", It probably carries over from season to season on old leaves nd stems. Again you should be able to read about this.
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Sorry David, I modified my post adding other fungicides meanwhile you were writing your answer!!!
What can you tell me about the other fungicides I added?
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The "conazoles" are triazole fungicides introduced in the 70s. They are all broad spectrum each having a slightly different spectrum of activity . They are especially active on Rusts and Septoria of cereals. Since their mode of action is limited to a single site they are often used in progammes/mixtures with fungicides having a different mode of action. ( to delay the onset of resistance).
Strobilurins ....we, ve discussed.
Chlorothanil is in its own class. Another broad spectrum fungicide ?...
Start spraying early in the season,,,,before the spots appear....xheck on Wikepia the life -history...I think there may be other comments on the Forum.
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I found only this:
"EPIDEMIOLOGY AND DISEASE CYCLE
S. pistaciarum (and S. pistacina) overwinter in fallen leaves that were infected while on the tree in previous seasons. Pseudothecial primordia appear on fallen leaves early and young asci develop from then until February to early March. Most ascospores are mature
and ready for discharge from late April through May, and are released during or after rain. The optimum temperature for the development of pseudothecia and asci of S. pistaciarum is 10ºC (50ºF). Infections due to ascospores of S. pistaciarum have an
incubation period of about 10 days. Pycnidia with viable conidia of S. pistaciarum have been found on fallen leaves throughout winter and up to July, but their role in the disease is unknown. Secondary infections are caused by S. pistacina conidia, which spread by rain or
sprinkler water, and may continue until late fall. Spermogonia production begins on leaves on the tree in mid-September and continues on fallen leaves until December. Their role is unknown. Nothing is known about the epidemiology of S. pistaciae"
CONTROL
Septoria leaf spots are controlled with preventive fungicide sprays. Dithiocarbamates (zineb, mancozeb) are recommended. Also chlorothalonil and copper fungicides are also effective, but must be applied after fruit have reached 1 cm size to avoid phytotoxic damage to very young fruit. Benzimidazole fungicides are also effective. Applications should begin when the first leaves unfold and repeated if necessary monthly until early June. None of these fungicides are registered for California pistachios."
and...
"Septoria leaf spot
Septoria leaf spot is caused by the specie Septoria pistaciarum (Mycospharella pistaciarum). In years with high diseases incidence S. pistaciarum may also attack the fruits. This species primary infections are produced by ascospores released from pseudothecia in overwintering leaves on the263
ground. These diseases are common and especially in years with rainy springs, they may cause heavy defoliant in late summer. Leaf spot from natural infections are round to irregular, 1-2 mm diameter, with 1 to 20 flaslike fruiting structures of the fungus (pycnidia). Pycnidia measure 60-108
mm in diameter, pycnidiospore are colourness, curved to scale-shaped, and 44-85.5 x 3-3.9 mm, with 3 to 9 septa."
So...I don't know if it is septoria pistaciae or pistaciarum and wath the difference is!
If we wold listen to this article I would have to treat them montly from spring untill june, is it?
So the "best" way I have is to give, for example, trifloxystrobin and a dithiocarbamate alternately, from the first new growth untill June?
Another study about septoria on pistachios of Arizonsa USA, says that fungicides should be sprayed during high humidity months, in July-August, but I don't know if I can apply the same timing, but is it true that I bought them in october and the disease was just on them!
Anyway, 3 days ago I sprayed penconazole because I had only that fungicide and in two days I'm going to give a second treatment of attack.
After that second treatment have I to use another one of these fugicides (a curative one) or I have to continue to use penconazole for this year?
If I have to use again penconazole have I to use a lower dose how many times?
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The answers are in the article....spores overwinter and are released in the spring , April..May after rain...When temperatures are above 10C. To my mind that could be anytime around March. new infections can occur monthly up to the end of July to mid September and maybe longer
Control should start when the first leaves unfold and continue every month until early June...that is if protective sprays such as the dithiocarbamates are used.. A thorough cover is essential!!!
Lets assume the two Pistachias are the same...at least as far as control is concerned.
Keep the sprays going from first leaf, every month, until at least June. You can use a dithiocarbamate on a routine every month basis, or dithio plus say a stribilurin at the same interval. Keep all new grothnprtected with a covering of fungicide.
I found only this:
"EPIDEMIOLOGY AND DISEASE CYCLE
S. pistaciarum (and S. pistacina) overwinter in fallen leaves that were infected while on the tree in previous seasons. Pseudothecial primordia appear on fallen leaves early and young asci develop from then until February to early March. Most ascospores are mature
and ready for discharge from late April through May, and are released during or after rain. The optimum temperature for the development of pseudothecia and asci of S. pistaciarum is 10ºC (50ºF). Infections due to ascospores of S. pistaciarum have an
incubation period of about 10 days. Pycnidia with viable conidia of S. pistaciarum have been found on fallen leaves throughout winter and up to July, but their role in the disease is unknown. Secondary infections are caused by S. pistacina conidia, which spread by rain or
sprinkler water, and may continue until late fall. Spermogonia production begins on leaves on the tree in mid-September and continues on fallen leaves until December. Their role is unknown. Nothing is known about the epidemiology of S. pistaciae"
CONTROL
Septoria leaf spots are controlled with preventive fungicide sprays. Dithiocarbamates (zineb, mancozeb) are recommended. Also chlorothalonil and copper fungicides are also effective, but must be applied after fruit have reached 1 cm size to avoid phytotoxic damage to very young fruit. Benzimidazole fungicides are also effective. Applications should begin when the first leaves unfold and repeated if necessary monthly until early June. None of these fungicides are registered for California pistachios."
and...
"Septoria leaf spot
Septoria leaf spot is caused by the specie Septoria pistaciarum (Mycospharella pistaciarum). In years with high diseases incidence S. pistaciarum may also attack the fruits. This species primary infections are produced by ascospores released from pseudothecia in overwintering leaves on the263
ground. These diseases are common and especially in years with rainy springs, they may cause heavy defoliant in late summer. Leaf spot from natural infections are round to irregular, 1-2 mm diameter, with 1 to 20 flaslike fruiting structures of the fungus (pycnidia). Pycnidia measure 60-108
mm in diameter, pycnidiospore are colourness, curved to scale-shaped, and 44-85.5 x 3-3.9 mm, with 3 to 9 septa."
So...I don't know if it is septoria pistaciae or pistaciarum and wath the difference is!
If we wold listen to this article I would have to treat them montly from spring untill june, is it?
So the "best" way I have is to give, for example, trifloxystrobin and a dithiocarbamate alternately, from the first new growth untill June?
Another study about septoria on pistachios of Arizonsa USA, says that fungicides should be sprayed during high humidity months, in July-August, but I don't know if I can apply the same timing, but is it true that I bought them in october and the disease was just on them!
Anyway, 3 days ago I sprayed penconazole because I had only that fungicide and in two days I'm going to give a second treatment of attack.
After that second treatment have I to use another one of these fugicides (a curative one) or I have to continue to use penconazole for this year?
If I have to use again penconazole have I to use a lower dose how many times?
Suggest you talk to local growers, extension workers , your co -op for local details!
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Sorry, tell me if I understood, I have to spray dithiocarbamate every month a or a dithiocarbamate plus a stribilurin every month, is it right?
If I'll spray both of them I have to spray them together in the same treatment or separately by few days?
Or I didn't undertood and you mean to spray a month a stribilurin and the next a dithiocarbamate?
Unfortunately there is no pistachio growers here, only grape, olive tree and other fruits growers, so I think none could help me here! :(
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I noticed some spots also on my cercis siliquastrum which were near my terebinths during autumn and winter!
Is it possible that septoria of my terebinths infected also my cercis?
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Good morning!
After a few days of rain I noticed that these spots have appeared on my pistachios from seed .
I took away the leaves with spots and I gave a treatment with penconaole at 0.2% and I will give another one next week.
My terebinths, near these plants semms to have no syntom but I treated them too.
According to you is it septoria, again, or something else?
(http://i60.tinypic.com/2j5dgs8.jpg)
(http://i58.tinypic.com/11s2kom.jpg)
(http://i59.tinypic.com/dg74g1.jpg)
(http://i62.tinypic.com/v66eee.jpg)