For more than ten years, a majority of orange groves in
Florida have been afflicted with 'citrus greening'. The disease has devastated millions of acres
of citrus crops throughout America and elsewhere.
Trees that succumb to this disease produce fruits that are
green, misshapen and bitter. They're
unsuitable for sale as fresh fruit or for juice. Most affected trees die within a few years.
Research into citrus greening has consumed well over $540
million of funding without a single recovered orange or cured tree to show for
it.
The assumed cause of citrus greening is a bacterium, Liberibacter,
originating in Asia and spread by an insect (Psyllid). However, presence doesn't indicate cause and
effect: it's not been possible to maintain the bacterium in culture to generate
experimental proof, and detection of the assumed culprit is based on DNA
analysis.
Treatment of citrus greening has focused on the mass
spraying of trees with the antibiotic streptomycin, soon to be joined by
oxytetracycline to kill the bacterium.
Both these drugs are important in treating human and animal disease, and
raise the obvious concern of fostering antibiotic resistance. Insecticides are applied to kill the insect
vector. Yet, the sick trees aren't
getting cured.
A GM virus engineered to deliver a bacteria-killing protein
derived from spinach is in the US regulatory pipeline, but its efficacy in the
field is unproven.
Some US universities are working on GM citrus trees
resistant to citrus greening. This is a
long, slow, expensive road (which might not have an end).
Meanwhile, Frank Dean, product development manager of
'Performance Nutrition' (agriculture and turf division of chemical supply
company, LidoChem Inc) noticed that the citrus greening pathology was similar
to diseases afflicting crops in the Midwest where corn, soyabeans and tomatoes
suddenly develop unexplained problems resulting in crop losses. Acting on a hunch, Dean demonstrated that every
visual sign of citrus greening could be induced with the herbicide glyphosate.
Note. Glyphosate is used on most GM crops and is
used on other crops to prepare them for harvest. If you're wondering what relevance glyphosate
has to orchards, it seems the herbicide is used in lieu of mowing between the
trees. This has come about because, as a
water-saving strategy, US orchards have replaced overhead irrigation systems
with micro-irrigation in which water is fed directly to the root area from
pipes laid along the ground. This
reduces water loss by evaporation but the presence of the pipes prevents
mowing.
Dean set about developing the Citrus Greening Recovery
Program. This involves bio-degradation of glyphosate residues in the soil,
restoring the soil microbial diversity and populations suppressed by
glyphosate, and replacing the soil micronutrients which glyphosate makes
unavailable to the tree. The Program
also applies several therapeutic doses of three vital amino acids which plants
poisoned by glyphosate can't produce: these include a plant hormone precursor
needed for healthy root development, and two amino acids which protect trees
from diseases and parasites.
A first trial of the Program focused on a 20-acre plot of
3,000 Valencia orange trees. The outcome
was that trees identified as "dead or dying", almost barren of leaves
and new shoots, and which had had no harvest for three years before treatment
now have a full canopy of leaves, an abundance of fruit and have generated
their third harvest.
The conclusion? It
seems that the assumed bacterial infection could be a symptom of a
poisoned and malnourished tree, not the cause.
And, as for the insect vector,
it's well-known that when glyphosate is applied, the plant's leaves turn
yellow and that the psyllid insect blamed for citrus greening is attracted to
yellow leaves.
No money changed hands during Dean's trial. Inputs were provided free if the grower did
the work (and stopped or limited herbicide applications).
The commercial cost of the Citrus Green Recovery Program
will be around $500 per acre. To put
this in context, the cost of growing citrus, including the possibly
counter-productive agrichemicals, is around $2,000-$3,500 per acre.
It appears there is a cheap, sustainable, scientifically
based, proven remedy for the mass poisoning of America's citrus groves. So, are the authorities rushing to promote it
and save their country's citrus fruit industry?
No, they're still pouring money into GMO, pharmaceutical,
and pesticidal 'fixes'. Dean has been
called "batsh*t crazy" and his presentation has languished unviewed
because it "smelled like a rotting dead fish".
In Dean's assessment, regulators "have painted
themselves into a corner": the amount of public funding flowing into
research on the supposed bacterium, along with academic assurances of
glyphosate's safety make it impossible for them to admit now that a mistake's
been made.
(Regulators are also very shy of treading on biotech
industry toes.)
Glyphosate isn't, of course, likely to be the only factor in
the ill health of the modern citrus groves: the year-on-year accumulation of
multiple pesticides in the soil leads to a build up of debilitating toxic
substances in the plant.
OUR COMMENT
Citrus greening, or the yellow dragon 'huanglongbing', first
hit the headlines back in 2010.
Reporting at the time listed a succession of devastating
diseases in the groves, the latest of which was citrus greening, and for which
the solution was going to be GM orange trees [1]. At the time, we commented on several possible
causes, all of which seemed to have a human origin, but the glyphosate-damage
option wasn't one of them!
The reactions of the establishment to Dean's work are
following an all-too-familiar pattern previously dubbed 'COWDUNG' *[2]. What this achieves is inhibition of
discussion and further scientific enquiry, plus a shoring up of the biotech
industry, the patents, and the scientific reputations and funding sources.
*'COWDUNG' - Conventional
Wisdom of the Dominant Group
'Saving our oranges' with GM is good PR, but what will
happen to our health-promoting oranges when the biotech industry realises
citrus greening can be 'cured' with GM glyphosate-tolerant (not antibiotic or
insecticidal) citrus trees?
If you want to avoid GM glyphosate-laced oranges in the
future, tell your regulators now that there may be a non-GM,
non-chemical alternative to 'curing' not only citrus greening but an awful lot
of other crop diseases and yield losses.
Most important of all ask for public funds to be focused on building soil and plant health
instead of 'fighting' disease.
Background
[1] HUANGLONGBING AND OTHER MOTHERS (Doc) - GMFS Archive, June 2010
[2] COWDUNG - October
2015
SOURCE:
·
Expert says there's a cure for citrus
greening - so why is it being ignored? GM Watch, 11.03.19
CC Photo USDA on Flickr
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