Africa's natural guard protects key crops
Turning natural predators on crop-eating pests and letting them slug it out to protect harvests has been successfully staged in the Asian arena for some time. Indonesia and the Philippines spring to mind. But now the big promoters, including FAO, are increasingly looking to the venue of Africa.
Integrated pest management (IPM), which also includes various plant protection methods like crop rotation and the use of pest-resistant varieties, got off to a good start in Africa in the late 1970s. Sudan cut the use of cotton insecticides by half and later the introduction of a wasp spectacularly controlled the mealybug across the cassava belt.
In the last few years the momentum has picked up again. Ghana has launched IPM as the national crop protection strategy, which includes controls on the importing of chemical pesticides. Elsewhere, countries including Burkina Faso, Cote d'Ivoire and Kenya, from where extension workers recently have been sent to the Philippines for training, have taken useful steps towards adopting IPM.
"African farmers are as excited as they are in Asia about experimenting with natural pests," says FAO specialist Peter Kenmore. "There's a tradition of serious local innovation that is too often overlooked, and the potential is vast."
The new developments in Africa owe much to the Asian success story. Rice farmers across Asia have shown that large savings per hectare can be banked using IPM. Together with policy changes these ring up multimillion dollar savings for governments. It is estimated that the Indonesian Government saved US$120 million in the first two years after adopting IPM as a national strategy.
In all, it's a big incentive that speaks across continents. The message has been carried by donors and agricultural scientists alike, but it has taken time to set up projects. And inevitably so. Partly because IPM developed fast in Asia as a response to the production problems of the green revolution. In the 1960s and 1970s the use of improved seeds, chemical fertilizers, pesticides and plentiful water increased yields remarkably. But at the same time, as unnecessary pesticides upset the natural biological order, along skipped the brown planthopper and other bugs.
The hopper created havoc. And blanket spraying of expensive, chemical pesticides only made matters worse. Other predators like spiders -- there can be hundreds of different insect species in a hectare of rice -- that could have preyed on the hopper were wiped out, while the destructive pest populations grew in resistance.
The search was on for more sustainable methods. And preserving the natural pest-predator balance -- the work that led to IPM as it was first developed began in the late 1950s -- and other methods of pest control such as resistant varieties seemed to provide useful answers.
IPM's big breakthrough came in Indonesia in 1986-87 when it was adopted as the national crop protection strategy and 57 pesticides were banned by presidential decree. This followed a brownhopper outbreak that seriously damaged the country's rice crop and set the nation's political alarm bells ringing.
Just as important, however, was the introduction of farmers' field schools which allow local farmers to harness their indigenous knowledge of natural pest control to IPM. It quickly proved to be a cost-effective method ideally suited for other regions of the world, particularly Africa, which was largely bypassed by the green revolution and did not develop the extensive agricultural extension systems found in Asia.
Later, the 1993 FAO Global IPM Meeting acted as a spur. African plant protection scientists and policy-makers were inspired by Asian IPM implementors. "It works. We must do this in Africa," was the collective cry, said FAO's Sulayman M'Boob. The delegation returned to their countries to put in place the framework for Africa-wide IPM initiatives and the scene was set for expansion.
But it was the increasing use of pesticides in commercial crop production, as well as the paramount need to intensify production in an international climate where large-scale subsidies are frowned upon that made IPM strategies increasingly attractive.
Take Ghana. Here the consumption of rice is increasing faster than any other staple, but there is a hungry gap between domestic production and demand. FAO estimates that by the turn of the century rice imports for the subregion will burn over US$800 million of precious foreign exchange. IPM then, if properly implemented, offers great potential for increased yields and savings.
But many hurdles straddle the path ahead. In the case of Asia, the region was primed for over 15 years with donor funds. This helped build agricultural extension services and expertise reaching right into the villages. "Getting funds for IPM projects these days is much more difficult. And without funds all the good work will grind to a stop," says Gerardus Schulten, who heads FAO's IPM group.
An answer from one quarter would be to look to the private sector for future investment. Major chemical companies have declared their support for IPM -- which allows the use of chemical pesticides only on a strict "need only" basis. But the real danger is that if they do become involved they have the power to shift programmes and strategies in line with their own interest to maximize corporate sales of pesticides.
Every day in the field, the distributors of chemical pesticides can be seen pushing their products. Using vast networks they offer various freebies and incentives to induce farmers and government officials to purchase insecticides. And this is not just an Asian phenomenon. Moreover, big spending of government revenue on pesticides wins a lot of friends and favours. And for many countries, including those in Africa, this can be a brake on moving towards IPM strategies.
Despite such problems specialists like Peter Kenmore remain sanguine. "There are always champions. Some may be interested for purely technical reasons, politicians might want to put it on their agenda to please supporters and attract votes. Even if you have a mildly supportive institutional environment, things can work and do happen."
But most of all, his faith is in the farmers and the training schools. "When we create study farms together it's a liberating experience, a discovery of knowledge by the farmer. They gain a deeper understanding and control over their fields." And it's this, above all, that will see IPM's natural front advance.