news, features, articles and disease information for the crop industry


Scientists Find a Cure for Pests in Maize

02 November 2011

AFRICA - No maize means no food in a large section of Kenya. And so any effort to save the crop from pests, diseases and increase yields is a welcome idea to not only farmers, but also scientists and policy makers.

Maize forms an important part of the diet for the communities in the East African region with Kenya leading in production and consumption reports All Africa.

Maize production in Kenya has always been faced with the attack of maize stem borer, an insect that eats the stalk of the plant, leading to substantial loss of the crop in the country. The insect attacks the leaves and growing point of the plant, stunting the growth and sometimes killing off the plant.

In an effort to ward off the attack of the insect, scientists in Kenya have developed a biological control system where maize is intercropped with Napier grass and desmodium, a legume. Both plants are animal feeds and are locally found in most parts of Africa.

Samuel Njihia a senior research scientist at Kenya Agriculture Research Institute (KARI), says the technology has taken eight years to develop.

"We have tried it on 71 farmer field schools of about 31,000 farmers and the results are significant because a farmer can now produce 3.5 tonnes per ha, compared to one tonne before the intervention," he says.

The Napier grass forms a perimetre around the maize garden to attract the maize stem borer moths which fly at night and are attracted by the scent of maize. However, they prefer the napier scent than maize.

About half of the remaining 40 per cent of the moths that enter the maize crop are pushed away by the smell of desmodium which is intercropped with maize.

Ms Julia Kariuki, a farmer from Thika District in Central Kenya, says her yields have more than doubled in two years after the introduction of the technology. "Out of two acres of land, I have been able to harvest five bags of maize compared to two bags I harvested two years ago before I started this technology," she says.


Mr Njihia says the focus on the push pull system has also benefitted the farmers by not only controlling the pest and increasing the maize yields at low cost, but also their livelihoods by increasing on milk production, improving soil fertility and biogas production.

Ms Kariuki attests to this saying she no longer has to cook her food using firewood and that milk yields from her three herds of cattle has increased. "Since the introduction of push pull system, my milk yields have doubled from about 10 litres to about 20 litres."


Despite the intervention and high yields, farmers are still faced with marketing of their produce and land shortages in some parts of the country.

Ms Kariuki says her group produced a lot of maize last season, but was unable to sell the produce because of low prices. She wants government's intervention and group marketing.

"Lack of good market has discouraged many farmers because they are paid peanuts for their milk and maize. If we could sell our produce collectively, it would reduce the use of middlemen and increase our incomes," she says.

With the success so far, registered Kenya scientists are focusing at how this technology can be scaled up in maize growing regions of East African countries. Since Uganda is also a maize growing country, this technology could help in increasing the yields.

TheCropSite News Desk

Our Sponsors