By Herbert Musoke
As cassava farmers cry over the damages and losses from whiteflies that cause up to 100% loss, experts at the National Agricultural Research Organisation (NARO) have announced various tips and methods to help farmers.
Dr Irene Bayiyana, a researcher/agricultural economist and the national invasive co-ordinator at NARO, explains they have been doing research with farmers in several cassava-growing districts to find a solution to the whitefly pandemic.
She explains that cassava is the second most important food crop in Uganda after matooke in terms of production and consumption.
The traditional growing areas of cassava are West Nile, the northern and eastern parts of Uganda. It is increasingly becoming an important crop in Uganda’s southern and western areas.
The crop (cassava) is mainly grown by smallholder farmers owning one to two acres for food and income generation.
Most of it is sold as dry cassava or flour milled from dried chips but gradually more and particularly in urban areas as fresh cassava roots.
Whitefly epidemic
Dr Bayiyana explains that the cassava crop had been invaded by whiteflies, a major pest in Uganda that transmits viruses, further damaging the crop and the root tubers.
“The eggs develop through instar stages and take about one month to mature. When they feed on the leaves, whiteflies cause damage and spread cassava mosaic diseases and brown streak virus disease,” Dr Bayiyana says.
These diseases manifest with different signs. With cassava mosaic, the plant has distorted leaves and stunted growth.
Leaf stalks have a characteristic of an S-shape. On the other hand, cassava brown streak is a devastating disease that causes root tuber production and quality loss.
Fighting cassava whiteflies
Dr Christopher Omongo Abu, the programme leader of the National Crop Resources Research Institute in Namulonge, Kampala, says they have come up with innovations geared towards fighting the whitefly and its effects.
“We are working with farmers to fight whiteflies. We are trying to find sustainable control methods. Whiteflies are the tiny insects that hide under the cassava leaves and are known for spreading mosaic diseases and cassava brown streak disease,” Omongo says.
He advises farmers to plant improved varieties that are less susceptible to the diseases.
A short-term solution is to reduce the population of whiteflies as the institute embarks on innovating more resistant varieties as a long-term solution.
However, conventional breeding takes long (about 10 years). Researchers at NARO have resolved that farmers adopt limited use of insecticide in the first four months when they (the flies) are young and feed heavily.
Research, however, shows that cassava at five months and above is mature and the flies cannot affect it much.
According to the findings, farmers are appreciating that spraying helps to reduce the whiteflies’ effects on cassava.
The main target farmers are those working on a large scale who can supply to National Agricultural Advisory Services, Operation Wealth Creation and other non-governmental organisations.
In the end, other small-scale farmers will also benefit because the 60% loss will be solved. The research is done under NARO working with 36 private farmer groups in 18 districts like Bugiri, Buikwe, Serere, Palisa, Kamuli and Luwero.
“We believe that if it is done right, it shall be recommended to farmers as the short-term solution fronted by NARO through the Ministry of Agriculture, Animal Industry and Fisheries,” Omongo says.
Magnitude of loss
Many cassava farmers are making losses due to whiteflies that attack the crop, threatening many who wish to invest in it.
Florence Nakato is one of the cassava farmers and a member of Matovu-Rural Farmers’ Organisation in Matovu village, Bugiri district. Nakato started growing cassava in the early 2000s and has been losing her crop because of whiteflies.
“Cassava does not yield because at about six to nine months, when you harvest, you find the stem empty and some that have tubers would, at many times, be rotten,” she says.
Gladys Nabirye, the chairperson of Ryemokyandi Farmers’ Association, a cassava farmers group with 169 members at Namuntenga-Kimbale in Muterere sub-county, Bugiri district, says in this area, people live on cassava as their staple food.
“Before the whiteflies evaded their area, they would harvest over two tonnes but now they harvest about 700kg or less, resulting in losses,” she says.
LEAD PHOTO CAPTION: Dr Bayiyana (centre) and Dr Omongo (right) inspect cassava for whiteflies in Bugiri recently. Photo by Herbert Musoke
