Forget about drought and animal diseases, armyworms are the newest threat to East Africa’s food basket
By Ben Oduor
A new epidemic now threatens to tear apart East Africa’s grain basket, quickly rising past drought and common crop and animal diseases generally known to affect the region’s agricultural sector.
This follows a new research announced by scientists at CABI, a research website, which confirmed that ‘a recently introduced crop-destroying armyworm caterpillar is rapidly spreading across Mainland Africa and could spread to tropical Asia and the Mediterranean in the next few years.’
CABI says the caterpillar, known as fall armyworm (FAW)-Spodoptera frugiperda– is native to North and South America and can devastate maize production, the staple food crop essential for food security in most parts of Africa. The worm destroys young plants, attacking their growing points and burrowing into the cobs.
The caterpillar, the researchers say, has been an indigenous pest in the Americas and had not previously been established outside the region.
It was named fall armyworm because it migrates into temperate North America in autumn (fall) to damage vital crops, mainly maize (corn) and more than 100 different plant species.
But in the past year, it was found in parts of West Africa for the first time, with Ghana and Nigeria confirming presence.
“We are now able to confirm that the fall armyworm is spreading very rapidly outside the Americas, and it can be expected to spread to the limits of suitable African habitat within just a few years,” Dr Mathew Cock, CABI Chief Scientist, revealed, adding:
“It likely travelled to Africa as adults or egg masses on direct commercial flights and has since been spread within Africa by its own strong flight ability and carried as a contaminant on crop produce.”
It’s apparent the worm’s invasion found Africa pants down. Government’s, communities and farmers had no past experience dealing with the pest.
According to UN’s Food and Agricultural Organisation (FAO), it took only eight weeks for the pest to spread to the six Southern African countries where there are suspected infestations.
From the West African countries of Ghana and Nigeria where various research groups confirmed infestations, the pest has been reported in South Africa, Zimbabwe, Malawi, Zambia, Namibia, Mozambique and Sao Tome and Principe.
However, as of January this year Zimbabwe remained the most affected country. FAO reported the presence of the worms- both the native African armyworm (Spodoptera exempta) and fall armyworm- in seven of the country’s eight provinces, with estimates of 70 per cent crop destruction in some areas.
To combat the threat, Zimbabwean government started circulating information and pesticides in a desperate move to salvage crops from the rigorously spreading worm.
Neighboring Zambia, whose over 100,000 hectares of farmland had been infested, according to BBC, dispatched army planes to spray the affected areas with pesticides.
East Africa’s response
And now East Africa is battling a similar threat.
In response to the worm’s invasion in 10 counties within Kenya’s Western, North and South Rift regions, the Ministry of Agriculture, Livestock and Fisheries issued a national alert and disseminated necessary technical information immediately it learnt of the pest.
It also engaged key stakeholders and development partners for concerted efforts towards containing the outbreaks, and constituted a multi-institutional team of about six bodies to offer technical guidance in the fight against the worm.
Despite the concerted efforts, farmers from the country’s food basket regions of western and Rift Valley have complained of invasions, worsening situation at the agricultural sector which is the lifeblood of Kenya’s economy.
In Rwanda, government opted for a joint effort involving the community, soldiers and government officials to eradicate the threat.
Early April, the country’s Minister for Agriculture and Animal Resources, Gerardine Mukeshimana, said the outbreak had so far been reported in 108 sectors (among 416 of the country) in 23 of 30 districts where they had infected 15,699 hectare of maize and sorghum crops.
To contain the deadly pest from spreading rapidly, Rwanda Agricultural Board (RAB) Director General Mark Cyubahiro Bagabe told a local daily that they had rallied different partners including Rwanda Defence Forces (RDF), the National Police, among others.
Bagabe said they had included integrated management methods, physical and chemical measures, provided field equipment such as manual and motorized sprayer pumps and protective gear, as well as pesticides to eradicate the threat.
The government, on its part, commissioned RDF soldiers to work with farmers in spraying chemicals on the affected regions.
“The pest has spread across the country. Using a car to deliver pesticide from Musanze, to say, Eastern Province, then to Western Province, was taking longer, yet the assistance was needed as soon as possible to salvage what we can which led us to use the RDF aircraft,” Acting RDF Spokesperson, Lt Col Rene Ngendahimana told The New Times.
Other East African countries Uganda and Tanzania have also reported invasion.
It’s difficult eradicating the worm
Fall armyworms attack time is unpredictable. According to UN’s Food and Agricultural Organisation (FAO), the pest can cause extensive crop losses of up to 73 per cent depending on existing conditions.
In Southern Africa, for instance, FAO says the pests attacked at the height of the effects of two consecutive years of El Nino-induced drought that affected over 40 million people, reduced food availability by 15 per cent and caused cereal deficit of 9 million tones.
Controlling the pest is also expensive since it can’t be eradicated with a single type of pesticide, especially when it has reached an advanced larval development stage.
Also, it spreads fast once it attacks and the invasion is diverse. Sources say the invasive species can lay six generations of around 50 eggs in a single location, leading to rapid colonization and destruction of territory.
To make matters worse, unlike the African armyworm that is visible on the plant, fall armyworm escapes detection by burrowing on plant stems making it hard for farmers spraying external parts of the plant to reach it.
Other than maize, fall armyworm attacks cotton, soybean, potato and tobacco crops easing its chances of survival, and when it invades, up to three-quarters of the crop can be destroyed.
However, as the search for a cure to the menace continues, FAO Sub-regional Coordinator for Southern Africa, Dr David Phiri, advises countries to develop capacities for rapid response.
“The countries need to maintain and, where needed, expand diagnostic laboratory, surveillance and response capacity as well as conduct assessments and research to enable rapid responses to recurrent and new threats,” Dr Phiri said.