News brief
Vaccination,
not culling, urged to tackle avian fluVaccination, not culling, urged to tackle avian flu
Mass culling of poultry to control avian flu has been deemed no longer acceptable. The United Nations' Food and Agriculture Organisation (FAO) and the World Organisation for Animal Health (OIE) ended a joint meeting in Paris in April with a call for vaccination of flocks. The change in emphasis has been driven by the realisation that the virus is so widespread in wild and domestic bird populations, particularly ducks, that culling alone will fail to control the disease. Culling is seen as no longer appropriate as the primary means of control "for ethical, ecological and economical reasons". In 2004, the two organisations urged the use of vaccinations as a targeted strategy along with other control measures, but did so less forcefully than now. Implementing effective vaccination programmes is expected to require US$100-120 million in aid to affected Asian countries over 3-5 years.
The Vietnamese agriculture ministry announced in March that it would soon
start vaccinating ducks in the Mekong Delta for H5N1 flu. Meanwhile, FAO
has announced that an H7 strain of avian flu has been contained in North
Korea (DPRK) through a combination of culling over 200,000 infected chickens
and vaccination of unaffected birds. FAO has praised North Korea for its
prompt response to the outbreaks detected on three poultry farms near
the capital Pyongyang but urged that surveillance measures remain in place.
Golden Rice re-engineered
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| credit: Syngenta |
Golden Rice just got more golden as the controversial genetically engineered
grain has been re-engineered with the maize gene psy, which encodes
the enzyme phytoene synthase, replacing one from daffodils. The switch
has boosted by 23 times the grain's content of beta-carotene, from
which the body synthesises vitamin A. This may answer criticism that the
amount of provitamin A in the original Golden Rice, which is not yet commercialised,
is too small to be beneficial (see also Focus
On 05-2). Syngenta developed Golden Rice 2, as the new version is
called, at Jealott's Hill International Research Centre in the UK.
Syngenta is donating Golden Rice 2 to the Humanitarian Rice Board, which
has supervised the Golden Rice development project since 2000. Permits
to allow planting of the rice in India and the Philippines have already
been received.
Controversial dam to go ahead in Laos...
The World Bank and Asian Development Bank agreed in early April to help
fund a controversial high dam planned for central Laos. The US$1.25 billion
Nam Theun 2 hydroelectric dam is the first major hydro-power project approved
by the World Bank in a decade and the first such venture since a report
in 2000 in which the independent World Commission on Dams set criteria
for big energy and water projects. Most of the electricity generated by
the 1,070 megawatt project - built by the Lao government, Electricite
de France and two Thai firms - will be sold to neighbouring Thailand,
earning foreign exchange for one of the world's poorest countries.
Critics contend that the social and environmental costs are too high even
before taking into account the risks of mismanagement, corruption and
cost overruns in the landlocked and secretive communist state.
...as study damns big dams
A study from Sweden's Umea University, published in Science
in April, catalogued the environmental harm caused by dams, which affect
rivers draining 54 per cent of the world's land area and carrying
60 per cent of its freshwater. Reservoir flooding, parched wetlands downstream,
loss of soil fertility on floodplains and disrupted animal migrations
are among the effects that, the authors say, "need to be accounted
for in global planning for sustainable river management". Another
study in the same issue of Science, from the University of Colorado
in the US, focused on the effect of all human activities on sediment flow
downstream and into the sea. It found that dams decrease sediment flow
while other human activities, notably deforestation, increase it. Excess
sediment flow can suffocate coral reefs and sea grass, while deficient
flow can render coastal areas vulnerable to erosion.
Genetically
modified rape leads to more harm to wildlife than its conventional counterpart,
according to a report released by Britain's Royal Society in March. In
side-by-side tests, the GM fields had fewer of the broadleaf weeds upon
which insects and birds feed. Whereas the conventional fields were sprayed
with herbicide to remove weeds before the rape emerged, the fields with
herbicide-resistant GM maze could be sprayed later, more effectively killing
weeds even though herbicide use was lower. As a result, the GM treatment
reduced by a third the number of weed seeds available to birds after the
harvest. Two years later, the GM fields still had a quarter fewer such
seeds than the conventional fields. Winter oilseed rape is the UK's biggest
and most profitable crop, occupying 330,000 hectares. Bayer Crop-Science,
which owns the patent on the GM oilseed rape, said it would no longer
seek to grow the crop in Europe.
A
survey of Chinese farmers growing experimental Bt rice found that none
had experienced the pesticide-related illness suffered by some farmers
growing conventional rice. The two-year study by researchers at the Chinese
Academy of Sciences and, in the US, Rutgers University and University
of California, Davis, appeared in an April issue of Science.
The participating farmers - 77 in the first year and 101 in the second
- grew the rice without help or advice from technicians, deciding whether
or not to apply pesticides based on observations of the severity of pest
infestations, rather than on any prescribed dosage. Farmers growing the
genetically modified strains applied pesticides less than once per season,
while farmers growing conventional rice varieties applied pesticides 3.7
times per season. Yields of Bt rice were nine per cent higher than those
of conventional rice.
A
tiny wasp is attacking eucalyptus trees in Uganda, deforming their branches
and leaves, according to the country's Forestry Research Institute.
The blue-gum chalcid, previously reported infesting eucalyptus trees in
neighbouring Kenya and now apparently widespread in Uganda, attacks mostly
nursery saplings and young trees, but older trees have also been damaged.
The Ugandan forestry department has called for restricted movement of
planting materials and the cutting down or burning of heavily infested
trees. Originally from Australia, eucalyptus trees have grown in Uganda
for about a century and have recently enjoyed renewed prominence as a
cash crop for subsistence farmers (see 
