Please help me ID this disease, white leaves

[LenaBeanNZ]

diseased 005.jpg

diseased 007.jpg

For the past 3 weeks this one Brown Cherry has shown very pale yellow new growth. A few days ago Ive also noticed some brown patches. The rest of the plant looks healthy, so do the other Brown Cherry plants on either side. The affected plant doesnt seem to have grown much though, you can see the other plants are a bit taller by now. Any idea what is going on here?

[LenaBeanNZ]

Had upload problems, here is the other picture.

Lena

[dice]

So you were looking at 120-180 plants this year? On the off
chance that it is infectious, I would say that this one can go.

Anyway, you can look through the pictures of mineral
deficiences on these pages:

http://4e.plantphys.net/article.php?ch=5&id=289

http://www.luminet.net/~wenonah/min-def/tomatoes.htm

[Medbury Gardens]

I had a Black krim cutting do the same thing during the winter in my tunnel house, the plant came away come spring and is now a large plant with fruit days away from ripe,
What about cutting off the infected part off??

[dice]

What about cutting off the infected part off??

Sure, you could try that. You could crush a couple of aspirin,
mix them with water, and water the plant with that, too. The
plant will react to the salicylic acid in the aspirin with an
increased immune response. If it is a disease caused by some
microorganism (fungi, bacteria, or virus), that may help the
plant overcome it. If it is a mineral deficiency, that probably
won't do anything, and new leaves will show the same
symptoms. (If it is a microorganism caused disease for which
the plant has no defenses at all, the aspirin probably will not
be enough to let it recover.)

[LenaBeanNZ]

Thankyou all for your responses. I cut the tops off the plant last night, now Ill just wait and see.

The plants on either side look healthy, so I dont think its mineral deficiancy. I feed my tomato-growing soil very well, withhorse manure, seaweed, blood and bone, comfrey, home made compost, fish emulsion, worm juice etc.

The aspirin idea is a new one to me, I have alot of questions... can you please tell me some more about how and why it works before I ask them all? Im very interested. Thanks

[dice]

The aspirin idea is a new one to me, I have alot of questions... can you please tell me some more about how and why it works before I ask them all?

Salicylic acid is used by plants as part of chemical signaling
pathways that become much more active when the plants
are under stress from disease. (Plants naturally use salicylic
acid to activate many of their disease defense mechanisms.)
Adding it in the form of aspirin solutions allows the production
of chemical defenses by a plant under attack from disease
organisms to ramp up faster than it would if the plant had to
produce all of its own salicylic acid.

How much of it is deactivated by other soil organisms and
chemicals before it can be absorbed by the roots and whether
it can be absorbed through the foliage are as yet unanswered
questions for me.

I could post URLs found on the WWW relative to these
questions, but they tend to be either technical biochemistry
papers that examine specific chemical processes within
plants or non-technical summaries without research results
(like this explanation).

From your description of how you prepare your soil, I would
tend to doubt mineral deficiency as the cause, too (unless
that specific plant has some kind of genetic defect that
interferes with its ability to use particular nutrients). What
made me think of that was the way that the damage tends
to start at the stem end of the leaf rather than at the tip or
at random locations somewhere in the middle of a leaf in your
pictures. A few different mineral deficiences show that same
characteristic.

[LenaBeanNZ]

Thankyou Dice! That makes sense now.
I think I rememer from highschool biology that ants contain alot of salicylic acid. I wonder what they do with it.

Plant is still alive, making an axial bud which I will NOT pinch out! Strange how the symptoms didnt start until it was quite a few weeks old already.

[tessa]

Originally Posted by LenaBeanNZ

I think I rememer from highschool biology that ants contain alot of salicylic acid.

that's called ant-acid.

[LenaBeanNZ]

Ah ha ha ha ha ha!

[dice]

Here is one brief summary of some research results on salicylic
acid and plant immune systems:

http://www.medicalnewstoday.com/articles/84713.php

[LenaBeanNZ]

Interesting article, thanks.

[dice]

A lot of the news articles are like that one, focusing on the
potential for using the SABP2 gene in GMO modification of
plants that don't already have it. GMO modification is not
required for adding salicylic acid to a plant to have a benefit,
though, as most plants where salicylic acid plays a large role
in their immune response already have it (else they would have
been more disease prone and probably gone nearly extinct
already, at least for cultivated vegetable crop cultivars).

[LenaBeanNZ]

Ive found another plant looking sick, the top half has curled up leaves covered in brown speckles. The one next to it is showing similar symptoms but less severe. Both are Polish Linguisa. Is that early blight?

If I use aspirin, how many mg should I use per plant? approx.

[dice]

If I use aspirin, how many mg should I use per plant?
approx.

I have no idea. I have heard 1.5 aspirins to two gallons of water.
(Since aspirins come in different sizes, that is not real useful.)
Another grower drops one aspirin in a planting hole at transplant
time, on top of fishheads, eggshells, bonemeal, and 4-6-4
organic fertilizer. (This is for healthy plants before they show
any symptoms of disease.)

I crushed two 500mg aspirins, mixed them with water, and
watered them in around the roots of a couple of plants with
verticillium wilt this year. I did not notice any ill effects, but
then the plants were already stressed, so it would have been
hard to tell.

On one plant, the stems that were covered with wilted leaves
stayed that way, and I ended up cutting them off. The plant
grew back new, healthy branches on the side where the wilt
had not progressed, so that dose of aspirin was clearly not
fatal or even severely toxic. On the other plant, all of the stems
had wilted leaves, and it never recovered at all, although it
stayed alive that way most of the summer. (The few fruits it
eventually ripened were quite horrible tasting, so if I see any
more like that I am pulling them rather than trying to save
them.)

Curled leaves on the top sounds like a virus to me. (We get
some cucumber and potato viruses on tomato plants here in
N. America that look like that.)