Combating
Pests without Pesticides: The Miracle of Bilogical Control
IFAD
is a strong supporter of environmentally friendly technologies for
the control of agricultural and livestock pests. It has initiated
and supported some of the most effective and well-known biological
control campaigns. Acknowledged as a pioneering donor, IFAD has
been the catalyst in successful campaigns involving a large number
of donor partners who joined in the deployment of innovative large-scale
pest-control technologies. These have either reduced pest infestations
to economic insignificance or have resulted in total eradication:
a rare achievement measured in purely economic and biophysical terms.
Given the Fund's track record as a major donor in biocontrol, developing
countries continually seek IFAD's assistance in initiating and helping
finance, through donor consortia, eradication campaigns against
insect pests.
IFAD
has assisted in mobilizing more than USD 125 million in donor funds
to support the control of serious pests and diseases.
IFAD's approach has been to help detect potential pest-induced
disasters as early as possible and to identify, design and support timely,
cost-effective and environmentally sustainable integrated-pest-management
strategies. These strategies help the rural poor avoid crop, fruit, vegetable
and animal production losses.
Supporting Innovative Pest-Control Technologies Influencing the Behaviour
of the Desert Locust: The Promise of Preventive Versus Curative Approaches
The desert locust is a relatively insignificant pest in
its solitary phase, in which it is a harmless grasshopper. The locust
becomes a major pest when, stimulated by favourable climatic and other
factors after a long dry spell, it begins to swarm. IFAD has supported
pioneering research work on biochemical signals (known as semiochemicals),
led by the International Centre of Insect Physiology and Ecology (ICIPE),
that has led to successful approaches that confine the pest to its solitary
state, thus avoiding swarm formation and providing a potential global
solution to the locust problem.
The IFAD-led donor consortium, which includes the United
Nations Development Programme (UNDP), the Swiss International Development
Agency (SIDA) and the Arab Fund for Social and Economic Development (AFESD),
is supporting the programme that has led to a scientific breakthrough
in the development of a viable biorational, preventive locust-control
strategy.
A New Approach to Controlling Locusts
The programme has so far achieved a high degree of success
and a great deal of international recognition. It has identified and investigated
the roles of semiochemicals that mediate in the complex behavioral dynamics
of the locust and prevent the gregarization and swarming of locusts in
breeding areas. The research has produced important results for influencing
the location in which the female locust lays eggs (oviposition), manipulating
sexual attraction between male and female locusts and retarding maturation
with pheromones.
Controlling Fruit Flies: Rehabilitating the Livelihood Systems of
Smallholder Fruit Producers through Control of the Carambola Fruit Fly
The carambola fruit fly is a relatively recent introduction into the
Western hemisphere. This fruit fly is recognized as one of the most serious
among the tropical fruit pests, reported to infest about 30 host species,
comprising eight cultivated and 22 wild fruits.
The pest attacks, among others, important fruits such as the starfruit
or carambola, the Curaçao or Java apple, mango, guava, West Indian cherry,
the Sapodilla, etc. Other infested fruits include the tropical almond,
Suriname cherry, cashew, grapefruit, orange and mandarin.
The deployment of the male annihilation technique (MAT) is already showing
results (see charts).
MAT uses a powerful male attractant, methyl eugenol, mixed with a bioinsecticide
and strategically distributed among host trees. Male flies attracted to
the lure are trapped and annihilated by the bioinsecticide. The male population
is reduced to the point at which reproduction is no longer possible, leading
eventually to eradication. MAT involves sequential aerial dispersal of
fibre blocks through a precision dispensing machine fixed to an aircraft
equipped with instrumentation capable of interacting via satellite in
order to maintain grid position. Release flights are conducted under daylight
visual flight rules, normally at 450-900 m above ground level. The flights
distribute the blocks along flight lanes, separated by 100 m, that cover
the treatment area in a grid pattern.
Jackson Trap – cotton wick is imbedded in the trap. It is
dipped in the sexual attractant methyl eugenol, which only attracts male
flies. During the flight to reach the wick, the males become caught by
a special glue. The trap is used only for monitoring the male population.
McPhail Trap – A food attractant (protein hydrolysate or
fruit juice) is used in this trap and it attracts both females and males.
After feeding on the solution, the flies are prevented from flying out
of the trap – crashing against the walls and sinking in the solution.
Carambola Fruit Fly – Trap Catches, before application of MAT
– In Apura and Wageningen in Suriname (on the north coast of
South America), before the use of MAT, the number of flies captured exceeded
15 males per trap per month.
Carambola Fruit Fly Catches, 3rd Quarter 97 - After releasing
blocks impregnated with methyl eugenol and the bioinsecticide, the fruit
fly population was eradicated from the treated areas. In the untreated
area, Saramacca, the number of captured flies remains high.
Launching the Africa-Wide Biological Control Programme
The combating of the cassava mealybug in Africa represents the world’s
largest and most ambitious, successful biological control programme in
recent times. The success of the programme is reflected by the international
recognition it has received – it is associated with the 1996 World
Food Prize and the King Baudouin Award.
The pest was introduced accidently into Africa, where it was threatening
food security throughout the cassava belt from West to East Africa including
Madagascar. The search for a natural predator of the mealybug took place
in Latin America, from where the cassava was first imported into Africa
some 300 years ago.
More than 200 million people were about to lose their staple food across
some of the poorest parts of Africa. In response, IFAD funded an adventurous
search to discover a natural predator against the cassava mealybug in
South America. The large-scale programme that followed involved the introduction
of the natural enemy from Latin America into Africa through quarantine
in Amsterdam, mass-rearing/multiplication at IITA in Nigeria and Cotonou,
and aerial release in all infested countries of Africa.
It has been estimated that at least 20 million lives have been saved,
which with a total cost for the project of USD 20 million adds up to having
saved a life per dollar invested. The economic return of the project has
been investigated in great detail. The latest study shows a cost-benefit
ratio for the project of 1-200. This is a conservative estimate, limited
to a period of only 20 years, although the mealybug will now remain under
control for as long as cassava will be planted.
Search for Enemies of the Cassava Green Mite Ends Successfully
IFAD is also supporting other important initiatives against equally devastating
cassava pests such as the cassava green mite. Successsful IFAD-supported
research has led to the discovery of the phytoseiid Typhlodromalus
aripo, which was introduced from Brazil and is now bringing the cassava
green mite under control in southern West Africa and locally in eastern
and southern Africa.
More than 25 nations and multilateral agencies came forward and pledged
resources for the programme – a demonstration of international solidarity
and commitment in the face of an emergency of this nature. The programme
averted a serious threat to our environment and to the livelihood of millions
of vulnerable African farmers and herdsmen.
Using Environmentally-Friendly Control Against
Pest of Pulse Crops in South Asia
Millions of southern Asia's poor are now living in the shadow of a pulse-crop
crisis triggered by pest attacks. In India, millions of poor farmers in
the semi-arid tropics of the Deccan Plateau risk not meeting their household
nutritional requirements. Both the urban and rural poor, whose dietary
protein intake continues to rely on pulses, will need to drastically reduce
pulse consumption levels as pulse prices rise in the face of production
shortfalls.
Among the pests, the pod borer, Helicoverpa armigera, is of particular
significance (see slide).
The Helicoverpa is present in Africa and across Asia, and is the
single most important insect pest in the agriculture of southern Asia.
It attacks a wide range of crops including cotton, tomatoes, chillies
and sunflower in addition to pigeonpea and chickpea. It has become resistant
to a range of insecticides, resulting in increased production costs and
increased yield losses.
In bad Helicoverpa years' farmers produce insufficient seed to
warrant harvesting their crops. Crop losses in pigeonpea due to Helicoverpa,
alone, were recently estimated at more than USD 420 million annually.
In chickpea, pod damage ranges from 0 to 84% depending on location. Worldwide
losses in chickpea have been estimated at nearly USD 330 million annually.
Slides show a number of IPM solutions, including the use of biopesticides,
botanicals and the nucleo polyhydrosis virus (NPV), which is proving effective
against the pests.
Unlocking the Potential of Smallholder
Livestock Production: The Challenge of Addressing Destructive Pests and
Disease
Animals make a significant contribution to nutrition in
sub-Saharan Africa. Meeting the future demand for meat and milk depends
entirely on improving livestock productivity.
Animal diseases sharply reduce livestock productivity. Annual
losses of USD 4 billion represent appproximately 25% of the total
value of livestock production in sub-Saharan Africa.
Trypanosomiasis – or sleeping sickness – is the
single most important constraint to animal production in Africa. It is
caused by the tsetse fly.
IFAD is financing promising research on the sustainable
management of trypanosomiasis and the tsetse fly.
The tsetse trap is based on using a fly attractant that
lures the tsetse. IFAD-supported research at the International Centre
of Insect Physiology and Ecology (ICIPE) and the International Livestock
Research Institute (ILRI) led to the discovery that the tsetse locates
its host through the odour of cattle urine. ICIPE has done cutting-edge
research that has identified a chemical compound that releases the same
odour. This has proven successful in developing the tsetse trapping technology.
IFAD and its Partners Diffuse an Ecological Time Bomb: The New World
Screwworm
The New World screwworm is known to be one of the most destructive
livestock insect pests in the Americas. The presence of the New World
screwworm fly in North Africa was confirmed in late 1988. The fly, which
had never before been reported outside the American continent, is considered
the most threatening insect pest of livestock in the western hemisphere.
It could have spread rapidly to areas with suitable climatic and vegetational
conditions in the eastern hemisphere and caused damage to livestock, wildlife
and perhaps even human populations in Africa and the Near East. Eradication
of the fly has been achieved successfully in North and Central America
only through the sterile insect technique (SIT): aerially releasing a
large number of factory-sterilized screwworm insects over endemic and
outbreak areas to achieve control and subsequent eradication.
In an emergency response, IFAD acted quickly to design and
support a pilot biological control programme for the eradication of the
fly, implemented by the Food and Agriculture Organization of the United
Nations (FAO). The programme was initiated in December 1989 as a precursor
to a large-scale eradication campaign. Besides testing the feasibility
of transferring SIT to North Africa and its efficacy within the region's
environment, the pilot programme included: support for strengthening livestock
movement control and quarantine operations; assistance for a public-awareness
campaign and development of logistical support in preparation for the
large-scale eradication campaign. The foundation laid during the pilot
programme and the fly-release operations that began in December 1990 facilitated
success in the near-eradication of the New World screwworm population
from North Africa by early March 1991. By the time full-scale operations
started, the campaign was so successful that it had almost achieved its
main objective – the eradication of the screwworm from North Africa,
in record time.
The large-scale programme served to further protect the
area from the regeneration of the screwworm population and from any residual
focuses of infestation that may have remained after the pilot programme
had achieved an advanced level of eradication.
The successful execution of the programme involved a very
large number of participants that responded to IFAD's call to contribute
resources in cash and kind. The implementation of the USD 55 million
programme depended not only on the mobilization and smooth channelling
of financial resources, but on the carefully orchestrated inputs of scientists,
technicians, administrators and implementing agents, all working in a
united effort and on a scale of unprecedented magnitude.
The world's most successful eradication programme in recent
decades was the result of a remarkable international effort behind the
intervention. It represented the first time that so many partners of IFAD
in the international community, many of them with diverse agendas and
conflicting political leanings, came together under a common mandate to
combat the potentially most devastating pest of the century.
More than 25 nations and multilateral agencies came forward
and pledged resources for the programme – a demonstration of international
solidarity and commitment in the face of an emergency of this nature.
The programme averted a serious threat to our environment and to the livelihoods
of millions of vulnerable African farmers and herdsmen.
