CABI Blogs: hand picked... and carefully sorted

Protecting our chocolate supplies - controlling cocoa pests and diseases in West Africa

I love chocolate – I really do – but we take it for granted that it will always appear on the shelves of our local shops. Most of us are oblivious to the many pests and disease that are attacking cocoa plants around the world and the work of farmers and researchers to fight against them – cocoa is afterall big business. The latest issue of GRO-Cocoa, a twice-yearly cocoa newsletter funded by the US Department of Agriculture and published by CABI, includes articles about 2 strands of research offering hope for controlling insect pests and diseases in West Africa – source of 80% of the world’s cocoa:

1. Research in Ghana shows how weaver ants could be exploited to control cocoa mirids and other insect pests – this reduces pesticide use and its associated impacts on human health and the environment.

2. CIRAD have identified new sources of disease resistance in wild cocoa in French Guiana, which is now being used to breed clones with better resistance for the fungus Phytophthora megakarya in West Africa, and for local strains of the disease in French Guiana.

Disease outbreaks on the map

Earlier this month I came across an article in the BMJ about HealthMap, a website that automatically monitors and disseminates information on disease outbreaks; some of the people involved describe it in more detail in an article¹ in PLoS Medicine.

The traditional disease surveillance network suffers from gaps in coverage and sometimes from restricted flow of information between countries; the purpose of HealthMap, which has been operating since September 2006, is to bring together the large amount of information now available on the Internet from discussion sites, news outlets and the like. It is funded by Google.org, the philanthropic arm of Google, and available free of charge to users.

The Chinese Mitten Crabs US invasion reaches eastern coastline

The Chinese Mitten Crab (Eriocheir sinensis), originally a native of East Asia, quickly invaded the European coastline as well as the western coast of the US. Now it looks as if their pincher movement to invade the US is complete. Within the last week The Marine Invasions Research Lab, Maryland, has reported that the Chinese Mitten Crab has invaded two locations in New Jersey. In addition they're also reporting new sightings of the crab along New York’s Hudson River.

The Plot Thickens

Allotments are hip and trendy at the moment, but for how long? Well, a little longer than it would take to eat £15 worth of food from your local grocery store I hope. I am reliably informed that this is one year’s rent for an allotment in a particular area of South Oxfordshire. So, if you’re not into status symbols or looking for an apt place to flaunt your Birkenstocks®, allotments are also a great way of honing your green fingers when you haven’t got a patch attached to your home. Or, for those of you trying to avoid pests in your own gardens, spreading your Savoy cabbages over several plots!

EU soil maps atlas

As readers will know I have a fondness for the European Soil Data Centre (ESDAC) and their publications (see previous post). Well they have produced another corker with the Soil Atlas of Europe. The 128 page Atlas can be downloaded either as a complete or in parts pdf or as individual high resolution pdf or jpeg pages. With chapters covering the basics of soil characteristics, the soil of Europe, the global perspectives of European soils and key threats that Euro soils face, all with supporting regional maps on soil chemistry, physics and classification (see thumbnail), this publication should be in every soil scientists and map lovers electronic library. Image copyright remains with ESDAC 2008 

Waste no more!

As I was screening publications for the CAB Abstracts database this morning, I came across an environmentally encouraging bit of news – Anglian Water is producing enough biogas from its new advanced digestion system to deliver 980kW of energy at the engine without any further fuel requirements. The article (1) in the July 2008 issue of Water and Wastewater Treatment reported that the Anglian Water plant (Kings Lynn), where the new digesters are in operation, is currently producing about 12,000 cubic metres of biogas from about 11,000 tonnes dry solids. But how are they doing it?

An example of anaerobic digestion towers

You say tomato, I say cardioprotective antiplatelet factor

Several studies have indicated that tomatoes may help reduce the chances of heart disease (see for example "Organic tomatoes - better for your heart?"). But how might this work? A paper in CAB Reviews looks at the evidence that proteins which prevent the clotting of platelets may play a key role.

Platelets play a vital role in preventing excessive blood loss by clotting at the site of an injury. However, platelet aggregation is a central step in heart disease, including heart attacks and unstable angina, says Asim Duttaroy, from the Faculty of Medicine, University of Oslo. While aspirin shows some activity in stopping this aggregation, its action is relatively weak, and it can cause gastrointestinal disturbances and bleeding problems in some patients. Studies directly on platelets show that tomato juice and kiwi fruit juice are both potent at preventing platelet aggregation.

Researchers went further and tried to identify which components in the tomato juice had the biggest effect on platelets. Besides water, most of the juice was made up of soluble sugars, which had no effect, but once those had been removed, different components had different effects on clotting. They showed that the sugarless extract supplied in orange juice could reduce platelet aggregation in humans, 3 hours after drinking the equivalent of 6 tomatoes-worth.

The studies also showed that people who had known markers for heart disease were more sensitive to the extract than those who did not. While there is much still to be confirmed by more detailed study, Duttaroy says “Consumption of such tomato extracts as a food supplement could benefit public health by helping maintain platelets in an inactivated state and reducing the risk of thrombotic events mediated by platelet activation”. Which is good news, as you could enjoy the health benefit even if you didn’t fancy eating 6 whole tomatoes.

“Cardiovascular health benefits of tomatoes” by Asim K. Duttaroy appears in CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources.

Obesity & Diet -a new twist

It's not what you eat but what your mother eats that could set your bodyweight, suggest scientists at Baylor College of Medicine. Robert Waterland and colleagues studying mice with a genetic tendency to overeat found that successive generations of the mice became fatter. This increasing obesity was prevented by a diet rich in folate and B vitamins. 

Pesticides persist in ground water

Numerous studies over the past 40+ years have established that pesticides & herbicides, typically applied at the land surface, can move downward through the soils unsaturated zone to the water table at detectable concentrations. This downward movement of pesticide degradation products, formed in situ, can also contribute to the contamination of ground water. Once reached ground water, depending upon the chemical structure of the compounds and the environmental conditions, pesticides and their degradation products can persist for years.

Scientists at the U.S. Geological Survey (USGS) investigated the occurrence of selected pesticides (plus degradation products) in ground water. The group of scientists examined several of the factors (e.g. oxidation-reduction (redox) conditions and ground-water residence times), that can influence the likelihood with which pesticides and their degradation products are detected in shallow ground water at four study sites across the United States. Click here for the paper which is free to non-subscribers of Journal of Environmental Quality for July 2008.

New tool to fight viruses?

A new device caught my eye this week. Marketed by Aethlon Medical, it claims to treat HIV and other viral infections by removing viral particles from the blood. Aethlon claims the device could be used against HIV, hepatitis, and biological warfare agents such as Ebola and smallpox. Great news, but it sounds too good to be true. Could this really work?