Better solutions than GM in Kenya (11/8/2004)


See quotes at end from Director General of Kenya's International Centre of Insect Physiology and Ecology, amongst others.

See also the incisive article from the Kenyan press, 'Don't Embrace GM, Go for Homegrown Solutions'

And nice to see Rothamstead's Prof John Pickett FRS doing something constructive - for more on Pickett's less constructive side:

Non-GM alternatives in Kenya
1.Icipe Researchers Find a Way to Stop the Stemborer
2.Tapping into Nature's Arsenal to Fight Farmers' Enemies

1.Icipe Researchers Find a Way to Stop the Stemborer
Naftali Mungai
The Nation, 9 August 2004

The push-pull programme aims at controlling the stemborer, which causes an estimated loss of 15 per cent of Kenya's maize and other cereals, writes 'Nation' Science Editor NAFTALI MUNGAI

On June 18, the fraternity of the International Centre of Insect Physiology and Ecology (Icipe) honoured its founder director, the late Prof Thomas Risley Odhiambo, by renaming the Mbita Point field station after "TR", as he was fondly known by his friends.

But besides renaming the station after one of Africa's most illustrious scientists and visionaries, Icipe also showcased one of its most interesting works in sustainable agriculture that is having a far-reaching impact and changing lives in several districts of western Kenya.

When Prof Thomas Odhiambo founded the International Centre for Insect Physiology and Ecology (Icipe) in a car garage at the Chiromo campus of the University of Nairobi in 1970, some sceptics criticised such a development as premature, arguing that Africa was not yet ripe for science-led development.

But to Prof Odhiambo, the mission of Icipe was clear. One of its aims was "to transform the discoveries and innovations from advanced research and development work into first class ecologically-friendly, sustainable strategies for managing insect pest and vector populations so that they are rendered harmless both socially and economically."

Thus, when on June 18, the Icipe fraternity honoured Prof Odhiambo by renaming the Mbita Point field station after him, it was recognising one of Africa's most illustrious scientists and visionaries.

However, besides renaming the station after Prof Odhiambo, Icipe also showcased one of its most interesting works in sustainable agriculture that is having a far-reaching impact and changing the lives people in several districts of western Kenya.

One year after his death, resource-poor rural communities in Nyanza Province, where he was born, are reliving his dream by the thousand through the "push-pull" programme. This is a habitat management method that controls the stemborer – which causes an estimated loss of 15 per cent of Kenya's maize and other cereals, worth an estimated Ksh6 billion ($76.9 million) – by using fodder plants. The programme also increases milk production.

Push-pull is a repellent and attraction diversionary strategy that uses different plants for the management of cereal stemborers. The stemborers are repelled from the main plant (maize or sorghum) and are simultaneously attracted to a trap plant, usually napier or Sudan grass, where they go and lay their eggs.

But push-pull is not only about controlling stemborers only. It is also controlling Striga hermonthica – one of the most noxious weeds known in the world, aptly called the African witchweed, and kayongo in Dholuo.

The striga weed, which has strikingly beautiful pink flowers, is the bane of maize farmers wherever it is found. It attaches its roots to those of maize, literally sucking the maize plant dry by imbibing nutrients that the maize would otherwise use for its growth, and will only germinate in the presence of maize or other cereals such as sorghum.

Says the head of the Habitat Management Programme at Icipe, Dr Zeyaur Khan: "During attempts to control stemborer damage to maize by intercropping with repellent plants, the fodder legume silverleaf, Desmodium uncinatum, was accidentally found to reduce the incidence of infestation by the African witchweed, Striga hermonthica. This reduction was found to be significantly greater than that observed with other legumes such as sun hemp, soybean and cowpea."

In Africa, the intercropping of maize and legumes has been practised for a long time and the most common system is the intercropping of maize and beans.

The push-pull system relies on a carefully selected combination of companion crops to be planted around and among the maize or sorghum plants for the manipulation of pests and their natural enemies. Dr Khan says that both domestic and wild grasses, often ploughed under in modern single cropping practice, can help protect the cereals by attracting the stemborers.

The grasses are planted in a border round the maize or sorghum fields, where invading adult moths become attracted to chemicals emitted by the grasses themselves.

"Instead of landing on the maize plants, the insects head for what appears to be a tastier meal. The grasses thus provide the "pull." They also provide a haven for the borer's natural enemies, where they are devoured as they seek refuge," says Dr Khan. According to him, good trap crops include napier grass (Pennisetum purpureum) and Sudan grass (Sorghum vulgare sudanese), a type of wild sorghum.

The "push," which is the repellent effect, was initially provided by molassses grass (Melinis minutiflora). But now, it is provided by a nitrogen-fixing leguminous plant that also provides fodder for cattle, the desmodium (Desmodium uncinatum), which is native to Latin America. "It came to Africa about 50 years ago after seeds were imported from Australia," said Prof Lester Wadhams, the head of the Biological Chemistry Division at Rothamstead Research Station in the UK.

Dr Khan says that as they were working with "push-pull" to control stemborers, they noticed that where desmodium was planted, the maize fields had less striga germinating.

Striga, which is native to Africa, causes maize losses of between 50 and 80 per cent. In the US, it is controlled by exposing it to ethylene continuously so that it keeps germinating, burning itself out in the process. But Dr Khan says that, "This is a very expensive method that only very rich countries like the US can afford."

In the fields, desmodium is planted in between the rows of maize. Because it is a low growing plant, it does not interfere with maize growth and has the advantage of maintaining soil stability and improving soil fertility through its nitrogen-fixing action. It is also easy to harvest and serves as a highly nutritious animal feed.

Dr Khan says that a ground cover of desmodium, interplanted among the maize, reduces striga growth by a factor of 40. The desmodium ground cover also reduces soil erosion, conserves water by acting as a mulch and provides fodder for cattle.

According to Dr Khan, more than 2,000 small-scale farmers covered by the Icipe programme have significantly increased their maize yields and milk production. "Fodder produced by the 'push-pull' farmers contributes to production of one million litres of milk annually," he says.

He adds that 300 farmers are now producing desmodium seed for income generation and are linkedto the Western Seed Company. "Extra income from push-pull has helped more than 300 farmers to send at least one child to secondary school," adds Dr Khan.

It is estimated that by the end of 2006, at least 10,000 farmers will benefit from the "push-pull" strategy. But by the way the technology is spreading, Dr K

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