Mozambique: WEMA maize shows promising resistance to destructive fall armyworm

Scientists have observed unexpected benefits in Mozambique’s Water Efficient Maize for Africa (WEMA) field trials that could well be a game changer in efforts to ensure Africa’s food security.

Though the maize varieties were genetically engineered to withstand drought and the vicious stem borer pest, they’re also showing promising resistance to the destructive fall armyworm pest, which arrived on the African continent in 2016 and continues its devastating advance.

Early results from Mozambique indicate the genetically modified WEMA seeds can offer significant protection against insect pests — without the use of pesticides.

This has positive implications for the other nations that are developing WEMA varieties, including Tanzania, Uganda, Kenya, South Africa and Ethiopia.

In Mozambique, the WEMA seeds are being tested on a 2.5-hectare confined field trial site at Chokwe in the Gaza Province, some three hours’ drive from the capital Maputo.

Ordinary local maize varieties, which are conventional, and the WEMA seeds, which are transgenic (GM), were planted last year to provide comparisons, and the results have exceeded the expectation of scientists working on the project.

No pesticides or insecticides were applied at any point in time in the life cycle of any of the plants. Four weeks after sowing the seeds, scientists analyzed the level of infestation by fall armyworm and other pests in the maize fields. “The leaf damage is higher in the conventional material than the transgenic one,” Dr Pedro Fato, the plant breeder in charge of the WEMA project, told Joy news during a visit to the field trial site.

“Here we have a combination of insect pressure from stem borer and fall armyworm. There was more than 30 percent [difference] on yield between the conventional and the transgenic, which means WEMA protects about 30 percent of the yield. The WEMA material shows resistance to both insects,” he noted.

The results are important because maize is a major staple in Africa, consumed by more than 300 million people. But the stem borer is a major pest that destroys maize by eating through the plants, leaving them struggling to survive. In many countries, fall armyworm is proving to be equally destructive.

Currently, farmers try to control these pests through the use of pesticides. Farmers in Mozambique say they have to spend a lot of money on pesticides, and they fear using the products could endanger their health.

“When I plant maize, pests attack them. I use pesticides to stop them,” explained Armahdo Bule, 59-year old farmer. “I know that using the pesticides without personal protection could give me diseases. I know that using pesticides is not good because it could give you problems. But we still use them,” he added

The pests also greatly reduce crop yields. “Stem borer is a biotic stress that Mozambique is concerned about, especially in this [Chokwe] area where there is a lot of heat,” Fato said. “It occurs throughout the country and sometimes causes yield loss of more than 40 percent.”

Further compounding the problem of pest attacks is the worsening weather. “Drought is another big challenge we farmers have to deal with repeatedly,” said Tabusa Arije, president of the local farmers association.

“The way the climate is changing has brought a lot of problems. Last year, we planted beans in July, but we didn’t make anything because the rain didn’t come and the temperature was high,” he noted.

Officials managing irrigation services in the country are equally concerned, saying the drought problem has gotten worse recently and led farmers into debt situations.

“There was a bad drought in 2016 and there was no water in the irrigation canals,” said Soares Almeida Xerinda, board chairman of the government irrigation organization Hydraulics of Chokwe.

“The impact was very bad because the farmers lost the crops that they have… Some farmers work with the banks to get inputs including seeds and fertilizers but until now, they still face the consequence of the drought.”

To address the problem facing maize, the African Agricultural Technology Foundation (AATF) launched the WEMA project, a public-private initiative that aims to produce conventional and genetically modified maize resistant to drought and pests.

The WEMA varieties are being developed through a collaboration between the International Maize and Wheat Improvement Center (CIMMYT) and government research institutions in six African nations using gene technology donated by Monsanto.

Since the resulting seeds are royalty-free, local seed companies can make them available to smallholder farmers at affordable prices.

“The project aims to develop and avail to farmers drought-tolerant and insect-protected maize varieties using a range of approaches, including conventional plant breeding and genetic modification,” said Dr Denis Kyetere, AATF executive director.

“These varieties will improve yields under moderate drought and protect maize from insect-pest damage,” he said.

Conventional WEMA varieties already have been introduced onto the market in target countries, except Ethiopia, which is currently testing the conventional varieties and preparing for drought-tolerant and insect-resistant (Bt) genetically modified maize confined field trials.

In 2016, South Africa became the first project country to commercialize Bt maize for use by smallholder farmers. Mozambique hopes to release the WEMA maize as the country’s first genetically modified organism.

The scientists are excited to discover that the Bt WEMA maize is also showing partial, but significant resistance to the fall armyworm, which has already spread to almost 30 African countries, destroying maize and other crops.

The pests are especially destructive because they don’t respond easily to pesticide applications and reproduce very rapidly.

In Mozambique alone, between 282,000 and 712,000 tonnes of maize were lost to the fall armyworm last year, costing the country’s economy between $83.8 and $208.7 million.

According to a report by the United Kingdom-based Center for Agriculture and Biosciences International (CABI) on the potential impact of the fall armyworm pests in Africa, which was commissioned by the UK Department for International Development (DFID).

Fato said the additional resistance to fall armyworm is good news for Mozambique’s agricultural sector, although that was not the intent of the research work.

“To control stem borer and fall armyworm, the farmers use a lot of insecticides and the cost of insecticide is higher particularly for the fall armyworm. So if you can produce maize that doesn’t need any protection in terms of insecticide, that will help the farmers a lot, in terms of yield.”

Farmers in the vicinity have already visited the WEMA fields and are excited about what they saw. “WEMA is providing solutions for problems and will increase productivity,” said Armahdo Bule.

“WEMA is welcoming because it will help us deal with diseases and drought,” said farm leader Tabusa Arije. “We are waiting eagerly to get the seeds.

"We are teaching ourselves about the seeds, how to apply pesticides and ensuring technology transfer with the hope that tomorrow, with WEMA varieties, things will be okay.”


This is the second — and perhaps last — of the confined field trials for insect resistance trait in Mozambique. Later this year, some of the varieties will be tested for their ability to withstand drought. Fato expects a smooth process that will eventually allow the WEMA varieties to enter the market and reach the farmers.

“In Mozambique, the regulation is in place,” he explained. “And that is why we certain we shall be able to plant these first transgenic materials. I hope that other crops will follow. The regulation is really conducive to GMO technology development.”

Soares Almeida Xerinda, the irrigation company official, agreed. “The WEMA variety will be a very important product because when you get involved in agriculture, you will always have a drought.

"Even if you have an irrigation system, you can always save water. Water is not in abundance. If you can save the water, you can use it for a long time including when you have a drought. The WEMA project is a good initiative.”