First phase of Ghana cocoa spraying campaign over 

KWABENA SARPONG AKOSAH / Reuters 5aug02

KUMASI, Ghana--The first phase of a government-sponsored mass spraying campaign of Ghana's cocoa farms to combat the fungal black pod disease has ended, a top official from cocoa industry regulator Cocobod said.

Ghana is the world's second biggest producer of cocoa after neighbouring Ivory Coast and its output was affected significantly by black pod last year.

Kwame Sarpong, chief executive of Ghana Cocoa Board (Cocobod) told Reuters in an interview on Sunday that the first part of a three-stage campaign started in the first week of June and ended in July.

He said the second phase would run from mid-August to the end of September, while the last phase would begin in October.

Although the disease is endemic throughout West Africa, a particularly virulent form called phytophthora megakarya arrived in Ghana from Nigeria in the late 1990's.

The fungus infects pods and turns them completely black and rotten. The most significant economic loss arises from the infection of pods in the two months before they ripen.

Sarpong said that not all growing areas were being treated for black pod, only those where the disease was endemic.

He said farmers who were not in areas prone to black pod but still wanted to spray against it would have to buy their own fungicides.

"It is this group of farmers who are complaining of a shortage of fungicides," Sarpong said. "There is adequate fungicide in all the black pod prevalent areas we are spraying."

But farmers in Assin Fosu and Twifu-Hemang-Lower Denkyira in Ghana's Central region said spraying against both insect-related diseases and black pod had not started in their districts because of chemical shortages.

Some crop analysts in Kumasi said several areas in Central region were also having problems with capsids.

Capsids or mirids are small insects which suck sap from trees and pods, causing infection and ultimately the death of a tree if left untreated.

Sarpong said capsid control would start in the middle of August and added that like black pod, capsid control would only be carried out in districts prone to attack.

From the Ghana Cocoa Board Website:
INFESTATION CONTROL ACTIVITIES

The Division has eighteen (18) “Disinfestation Zones within which trained pest control staff operate from strategic locations including the ports, regional capitals and a few District Offices. The operational staff inspect storage sheds and carry out the disinfestation of produce to ensure that only insect-free produce is exported. At the ports every parcel of cocoa is fumigated with Phosphine to completely disinfest the produce before shipment. In addition to insect control activities rodent control operations are also carried out by the Division on all storage premises to prevent rodent damage to produce in storage.

source: http://www.cocobod.org/Publish/qcontrol/page1.html  7aug02 

Phosphine (PH₃), also known as phosphane, hydrogen phosphide or phosphorus hydride, is a grain fumigant, an industrial gas used in silicon chip manufacture, an air pollutant and a natural product of swamps and sewers. 

The Codex Alimentarius (FAO/WHO, 1993) sets out the following Maximum Residue Level (MRL) and Acceptable Daily Intake (ADI) pesticide residues in food for human consumption. The levels are expressed as total phosphine and phosphide, measured as phosphine (PH₃). The MRL is 0.1 mg phosphine per kg commodity (expressed henceforth as ‘parts per million’ (ppm)) for cereal grains, and 0.01 ppm for some other commodities. The ADI is marked as "Not necessary", but a note states, "Good usage practices should ensure that residues are not present at time of consumption." The United States EPA also allows up to 0.01 ppm phosphine in processed foods, requires "…that under no condition should the formulation containing aluminum phosphide be used so that it or its unreacted residues will come in contact with any processed food…" (USEPA, 1988).

NIOSH Alert: Preventing Phosphine Poisoning and Explosions during Fumigation  http://phosphine.com/whiffs/99-126.pdf