Soil-dwelling worms threatening farmers’ livelihoods
Channel: Science & Development Network
Date: 2019-07-19

“Tomatoes are an easy target for nematodes. The overall damage caused by nematodes is both direct, on the plants, and indirectly, in terms of the cost of input that the farmers have to incur.

 “The seedlings are infected from the day they start to grow. During this early stage, the infection is still mild, and the farmer transfers this onto his farm,” explains Coyne, adding that after about two months, when the tomatoes start to bear fruit, the effect of the nematodes then starts to show. 

Sarah Karori, a retired primary school teacher, has been a farmer for over 40 years, cultivating crop plants and fruits such as banana and mangoes. “When I was farming French beans, we used to sell it to a cooperative society and there was a period I earned 120,000 Kenyan shillings (about US$1,150) that I used to pay school fees for my son who was at the Catholic University,” she says. But things have turned quite bad. 

“We water the plants, but, they do not seem to take up the water, and instead they wither and eventually fall down,” Karori tells ScieDev.Net.

She has been using all sorts of fertilisers and chemicals on the crops to address the problem but the yields have been continuously going down for about a decade now. 

In Kenya’s Nyandarua County, Jesse Kamutu’s farming efforts have not been paying dividends lately. The 58-year-old Kamutu has been farming since 2000 after his wife initiated potato farming. 

The two have been using their 15 acres of land for cultivating potatoes. “I switched to producing and selling their potato seedlings in 2008,” Kamutu says.

Kamutu learnt about nematodes in 2018 when researchers from icipe visited his farm where his production had been on the decline each passing harvesting season.

 “I used to get up to 100 bags of 100 kilograms of potatoes per acre, then it reduced to 50 bags and eventually to 30 bags. I have been making losses with each investment,” he explains.

Kamutu uses the proceeds from his farm to sustain his family and educate his only child. He also employed about ten workers on his farm.  

“We would sell about 100 kilograms of potatoes at about US$43 during the high season,” he says. “On a good season, we could make at least about S$1,900 from each plot of land. Today, the nematodes have caused me great losses and I am considering a shift from potato farming,” he adds, with a downcast look. 

Scientists from Kenya-headquartered icipe — an organisation that addresses challenges posed by insects and other pests— have been visiting smallholders  across the Sub-Saharan Africa on research missions aimed at understanding the extent of the damages caused by these worms.

Ruth Muthoni Kihika, a doctoral candidate at icipe focusing on chemical ecology of plants and root knot nematode interactions, says that it is one of the challenges farmers are facing in Africa due to its devastating effects on crops. 

“You see the yields reductions yet most farmers will not know that the problem is the root knot nematodes, which are actually below the ground so they are not seen yet you can see the effects above the ground,” she tells SciDev.Net.

It is a very serious problem in Africa but there is also the challenge of the lack of data on economic loses that nematodes cause. Most of the data that is available in terms of yield loses come from Europe or America but we don’t have much of this in the African continent yet when you visit farmers you will see that nematodes are a great challenge for them, says Kihika.

https://www.scidev.net/sub-saharan-africa/farming/feature/soil-dwelling-worms-threatening-farmers-livelihoods.html