Date: Thu, 29 Jun 2000 10:40:35 -0400 From: "Tom Massey" <massey@fmhi.usf.edu> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg1952$foo@default> Subject: RE: Strange disease
Hey Peter and all:
I have had this problem occasionally with a few plants. I think I wrote in
about it once or twice (?), and we have discussed it at our local club once.
Here are a few observations (delete now if you don't want long stories!):
It seems to strike at both hybrids and species equally, with the exception
of S. psittacina. This may be pure happenstance, who knows?
First time I saw it was about two years ago, (I have been growing Sarrs.
since about 1976).
This is definitely not associated with any of the root borers or cutter
wasps.
There may be two problems, one rhizome related and one pitcher and leaf
related, or they may constitute the same disease.
Description: On the pitchers and leaves: The spot can start anywhere on
the pitcher and may at first look like the red/black spots that you see
occasionally. This spots slowly expands and definitely destroys the local
vascular tissue. The result will be that if the spot is on the lower stem,
the entire pitcher will loose turgor and wilt. This happens very quickly.
An apparently healthy trap one day will be wilted the next. For a grower
with much experience, it will clearly look different from a mature pitcher
that is slowly dying from old age or some other damage; the difference being
that the entire pitcher wilts at one time. If the spot starts higher on the
pitcher, you will often find that the portion of the pitcher above the spot
all the way to the top of the pitcher wilts and turns brown. The result is a
pitcher with a strange dead streak running up one side of it.
This is not the same as dead spots caused by pitchers with a full gullet of
insects. In those cases the dead spot is at the point of contact with the
insects inside the pitcher, and as often as not the pitcher above remains
healthy.
If the pitcher is left on for a few days, there seems to be a gray fuzz
(how's that for scientific terminology!) that forms on the spot. I always
though that this was a fungal problem and I was seeing the fruiting bodies,
but here I am out of my expertise.
I recently saw what looked like this problem in the wild for the first time
when I took Andrew and Peter from NZ out to see our local S. minors.
It seems to me that the spot does not necessarily migrate long distances up
and down the pitcher, although there is a rhizome problem that may or may
not be related.
This problem disappears in the winter(even here in mild Tampa).
I am not sure but it seems loosely associated with occasional problems with
the teardrop scale, but it could also be that stressed plants are more
susceptible.
I have used Captan, Benlate, Zerotol(sp), chipco/alleatte(sp), -- and just
in case the vector was bugs, malathion and ortene. I have never lost a
plant from the problem, altho you can loose some pitchers. After I cut off
infected pitchers I sterlize my razors, just in case.
Well thats most of it for the pitcher/leaf part of it.
Oh yeah, Neps don't seem to be susceptable.
Tom in Fl.
-----Original Message-----
Behalf Of CALIFCARN@aol.com
Sent: Wednesday, June 28, 2000 5:29 PM
To: Multiple recipients of list
Hey folks, Peter here at California Carnivores.
Here at our nursery we have gotten several phone calls from people in the
southeastern United States describing a weird problem with Sarracenia they
grow outdoors. All claim that the lower stem of the pitcher, where it joins
the rhizome, or the ala near the bottom of the pitcher tube, begins to turn
red or brown and rots, causing the pitcher to collapse and wither. Only one
phone caller noticed webbing inside of the pitcher, which may or may not be
of the grass-cutting wasp Isodontia. This latter pest usually results in the
upper part of the pitcher toppling, due to the nest prepared inside of the
pitcher, so I do not think this pest is responsible. Also, no one reports to
see the reddish debris chimney coming up from the rhizome as would be the
case for Sarracenia root borer. All these growers report the same symptom:
rotting of the pitcher's lower stem, causing the pitcher to fall over and
die. One claimed the "disease" seems to spread into the rhizome. We have
gotten about eight phone calls in the past two weeks describing the exact
same phenomenon, from states like Texas and Georgia and Florida. Anyone have
any clues?
Joe Harden asked me (before the conference) to describe the unusual
fungus that has bothered our Sarracenia. If you can imagine a pitcher made
of
paper, and someone holding a lit cigarette or lighter to various parts of
the
leaf and what it would look like (browned and burned), that is the best
description I can give. The Domaine seems to be controlling it but I'm
having
to apply it every 10 to 14 days. I still suspect it is some form of
anthracnose, and as I explained previously, it seems to have started in
sycamore trees out front of our greenhouse.
Th-th-th-th-th-that's all folks! Peter
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