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Published Date: 2011-11-02 12:29:13
Subject: PRO/PL> Black pod, cocoa - Cameroon: (CE)
Archive Number: 20111102.3254

BLACK POD, COCOA - CAMEROON: (CENTRE)
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International Society for Infectious Diseases
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Date: Mon 31 Oct 2011
Source: MENAFN News, Dow Jones Newswires report [edited]
http://www.menafn.com/qn_news_story.asp?storyid={6ff7b2f2-5494-4974-8cf8-06da2078ec8d}

Black pod disease hits central Cameroon cocoa crop
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Cocoa output in the Center Region, Cameroon's 2nd-largest producing
area, will likely fall due to an attack of black pod disease.

Unprecedented rainfall throughout October [2011] washed away chemicals
sprayed to protect cocoa pods leaving them exposed to the fatal black
pod, the Cameroon National Organization of Cocoa and Coffee Producers
said. "Sunshine has been rare and farmers have very little money left
to buy more fungicide. We fear there may be a 4-5 percent drop in the
main harvest in the Center Region."

The Center Region accounted for 40 percent of Cameroon's annual output
of around 240 000 metric tons in the last cropping year ending July
[2011], government and industrial data showed. The country is the
world's 5th-biggest cocoa producer.

[Byline: Emmanuel Tumanjong]

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ProMED-mail
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[Black pod (also called _Phytophthora_ pod rot) is the primary fungal
disease affecting cocoa worldwide. In Africa, the fungus-like
pathogens _Phytophthora palmivora_ and _P. megakarya_ are associated
with it, but 2 additional species are found in the Americas. _P.
palmivora_ is the most common pathogen and can cause yield losses as
high as 95 percent in very humid climates, with every pod affected.
Pods progressively turn a dark brown. Losses are most severe when pods
are infected during the 2 months prior to ripening. The disease also
causes stem cankers, which are estimated to kill up to 10 percent of
trees annually.

Black pod is spread by insect activity, mechanical means, plant
debris, water, and wind. Multiple infections from several sources may
occur in plantations, with epiphytotics developing from a series of
foci simultaneously. Genetic resistance is generally low in commercial
cocoa cultivars. Disease management is difficult and needs an
integrated approach, including cultural techniques, phytosanitary
measures, and targeted fungicide use.

To prevent problems with rain wash-off of foliar fungicides, such as
described above, trunk injections with phosphorous compounds have been
shown to be an effective alternative control measure against black pod
in Papua New Guinea (see link below). Similar methods are being used
in the control of _P. cinnamomi_ diseases in some tree species, for
example jarrah dieback and avocado root rot in Australia. The mode of
the protective action of these compounds against _Phytophthora_
species is still being investigated.

Maps
Cameroon and neighbours:
http://geology.com/world/cameroon-map.gif and
http://healthmap.org/r/1oxr
Cameroon regions:
http://www.mapsofworld.com/cameroon/maps/cameroon-map.jpg

Pictures of black pod symptoms:
http://blog.worldcocoafoundation.org/BlackPod.JPG,
http://www.tava.com.au/res/processing_20black_pod.jpg,
http://www.thecocoaplan.com/images/4.5_MG_0293.png, and
http://www.dropdata.org/cocoa/cocoa_pics/Ph_meg_section.jpg

Links
Information on black pod:
http://cacao.posterous.com/cocoa-basics-what-is-black-pod-cacao-farming,
http://www.tava.com.au/article_processing.html, and
http://www.dropdata.org/cocoa/cocoa_prob.htm
Black pod control:
http://www.publish.csiro.au/nid/39/paper/APP9900127.htm
(phosphonate) and
http://www.dropdata.org/cocoa/icm_bkp.htm
Molecular diagnostic methods for black pod:
http://www.ias.ac.in/currsci/jul102003/34.pdf
Economic impact of black pod and other cocoa diseases:
http://www.plantmanagementnetwork.org/pub/php/review/cacao/
_P. palmivora_ taxonomy:
http://www.indexfungorum.org/Names/SynSpecies.asp?RecordID=194605
_P. megakarya_ taxonomy:
http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=320483
Review of cocoa production in Cameroon:
http://www.feedar.interconnection.org/cocoa_coffee.html. - Mod.DHA]

See Also