Re: CULT: rot, aspirin etc

Margie, I thought this was so interesting, I'm posting the contents of
the link here so the info will be in the Mallorn archives, in case the
link you posted goes away.
======== copied info ==========
hopefully some useful material on biocontrol, etc./ Aspirin a day keeps
the virus,
                               bacteria and insects at play and away
                                           by mroboz
                                     21 July 2002 03:44 UTC

 Dear BDNOW'ers

   This last issue of "IPM Practitioner, V. XXIV, #5/6, was
particularily interesting.  It is about phytoalexins, how
 plants communicate with each other to protect against attacks of
various kinds, compost teas, etc.

   The classical form of induced systemic response uses the Salicylic
Acid (SA) pathway.  Aspirin, or
 acetylsalicylic acid, is just the hydrolyzed from of 2-hydroxybenzoic
acid.  SA levels increase in response to
 attack; solution of SA added to plants around the root zone lead to
increased levels of resistance proteina and
 increased resistance to pathogens.
   Dissolving 2 uncoated aspirin (5 grains, or 325 mg) in about 1L of
water gives a 4mM solution, which is not
 phytotoxic to most plants.  Plant experiments have ranged from 250uM to
15mM and for some plants, the
 protective doses are close to phytotoxic doses.  Plants that respond
well include tomatos, cucs, beans,
 potatos. Barley tolerated 15mM, brassicas around 10mM, asparugus only
4mM.
   The reason for large concentrations to induce the SA pathway for
resistance proteins is because added
 salicylate is immobilized by the plant.  It is enzymatically reacted
with glucose and is immobilized in the cell
 wall in the form of a glucoside. Free SA is released under attack and
transported via the phloem.
 Concentrations drop off quickly from the point of absorption.
    There are commercially produced analogs out there such as
isonicotinic acid (nicotinic in itself has
 insecticidal properties)
   Induced resistance against pathogens have been seen with sprays of
salts such as Kphosphate, Ksilicate
 and oxalate.  >From other sources I know of people who regularitly
apply kelp as a foliar spray for added
 resistance and nutrients.  If you have Reynoutria sachalinensis, or
giant knotweed, an extract of this weed can
 produce systemic resistance.
    Other pathways to resistance proteins include the activation of the
jasmonic acid (JA) pathway. eg. Plant
 wounding or attack by chewing caterpillars causes tomato plants to
release systemin, an octapeptide that
 triggers the conversion of linolenic acid into jasmonic acid (C18),
which then causes increased genetic
 expression of proteinase inhibitors and other proteins that make
foliage less digestible and less attractive to
 chewing insects.  These jasmonates also increase after wounding,
drought stress.
    Methyl jasmonate, one of the jasmonates methyl esters is isolated
from Jasminum grandiflorum.  Artemisia
 spp. growing near tomatos, when induced to be released from the
sagebrush, results in defensive proteins in
 those nearby tomatos.  This can be done by trimming the sagebrush.
     Some field tests have shown that tomatos sprayed with JA,.
dissolved in acetone, had fewer chewing
 insects such as fall armyworm (S. exigua), flea beetles (Epitrix
hirtipenis), fewer Western Flower Thrips
 (Frankliniella occidentalis, and fewer phloem feeders such as the peach
aphid (Myzus persicae).
 Two-spotted mite (T. urticae), leafminers (L. trifolii) are also
negetively affected with JA treatments.
    JA applications are associated with releases of plant volatiles that
attract natural enemies of chewing and
 sucking insects.  JA treament of tomatos doubled the number of
parisitized pupae of Spodoptera exigua
 produced by the wasp Hyposoter exiguae.  The fall armyworm is a low
density pest, but, JA induction had no
 effect on paristoids and syrphids that feed on high density pests such
as aphids.
    Me salicylate also signals to predators, in this case of the
2-spoted mite.  The predatory mites attracted
 were Phytoseiulus persimilis and Amblyseius potentillae.  This response
was shown on lima beans, cucumber
 rose, apple pear, tomato.
    The rest of this issue considered ryizobacter application, worm
casting product (Wormgold R) for improved
 health, growth and insect repellency. eg. in hibiscus against
whitefly.  Also, application of juvenile nematodes
 (H. bacteriophora) against slow and sedentary soil targets.
   The last section deals with intercropping corn and sorghum with wild
grasses to reduce stem borer moths.
     There are now more heat resistant brocculis that can be grown in
Hawai'i.  U of H, Manoa has shown that
 white, strawberry and yellow sweet clovers intercropped with brocculi
create living mulches and reduced
 diamondback moth (P. xylostella), cabbage webwrom (Hellula rogatalis)
and cabbage looper (Trichopusia
 ni).  More Polistes wasps were seen foraging., as well as spiders.
    In Vancouver's more temperate climate, rove and other beetle
populations would rise.

 Hope this has been of interest......cheers, Michael>
==================

--
Linda Mann east Tennessee USA zone 7/8

Tennessee Whooping Crane Walkathon:
<http://www.whoopingcranesovertn.org>
American Iris Society web site <http://www.irises.org>
iris-talk/Mallorn archives: <http://www.hort.net/lists/iris-talk/>
iris-photos/Mallorn archives: <http://www.hort.net/lists/iris-photos/>




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