Kampala, Uganda — For two seasons, Ms. Faridah Kabagenyi a farmer from Mukono 24KMs east of Kampala missed out on harvesting cassava not because she didn't plant any but because whenever she harvested, the tubers either had brown patches or some plants had not yielded anything.
Kabagenyi had not realized what the problem was until she visited a friend who faced a similar problem but had been helped by a researcher to identify it.
"My friend told me that my crops had the cassava brown streak virus that destroys the tubers before the crop matures," Kabagenyi laments.
She says the disease together with the banana bacterial wilt will soon deprive people of food since the diseases mainly affect staple foods that are consumed largely in the country.
Like Kabagenyi, many farmers in the country register low yields due to plant diseases but have with little knowledge of the cause. Mr. Yona Mukibi of Kayunga 71Km from Kampala says he has tried many ways to prevent the cassava virus from spreading to his one acre of land but his efforts did not help.
"Last season I planted cassava but it failed to mature, I decided to change the specie but the problem has persisted", complained Yona.
He at first thought that it was the cassava mosaic disease. When the symptoms changed, he learnt that his crops had been attacked by yet a new infection. Little did he know that it was the brown streak disease caused by cassava streak virus.
"Different from the mosaic, I realized my cassava had brown lumps and an unusual taste that even my pigs refused to eat," he said.
Cassava brown streak disease makes the top part of the plant appear healthy but eats up the tubers. The disease together with the bacterial banana wilt has spread to many areas of Uganda making the country prone to food insecurity.
The situation is worsened by the fact that the majority of the population depend on agriculture for income. If they cannot sell food and have to buy, then poverty and hunger are assured.
"Banana being the staple food for many Ugandans such diseases highly affect the local markets since it causes food scarcity resulting in high food prices", said Kabagenyi.
Banana wilt can affect the plant at any stage of growth depending on cause of the disease and its common symptom is premature ripening.
"At the flowering stage, the wilt can be introduced by flower visiting insects (such as bees) and at any stage, the disease can be introduced by using infected tools," said Mr. Robert Anguzu the Public relations officer at National Agricultural Research Organization (NARO).
Banana bacterial wilt affects 30 districts in Uganda while the cassava brown streak has spread to 20 districts. In 2001, the banana bacterial wilt disease started spreading in banana growing areas of Uganda. Since then research organizations have been making efforts to curb the disease.
The bacteria that begun in Mukono, has continued to spread to several parts of the country at a rate of 75 KM per year. Among the efforts to curb the disease was to train farmers how to control and prevent it from rapidly spreading. Dr. Geofrey Arinaitwe, a National Research Institute-based banana researcher, said the best way of averting the wilt is by breaking off all the male flower buds as soon as the fruits have formed.
"If the disease appears, cut down the stem and dig up all the affected plant so that it does not produce any new suckers then dig a hole where the plant was growing and bury all of the pieces completely," he advised.
He said if a farmer cannot dig a hole and bury the pieces, then he/she should heap them into a mound, cover them with leaves and leave them to decompose for at least six months before disturbing the mound.
He encouraged farmers to sterilise all tools used in cutting the diseased plants to avoid carrying the infection to other plants.
"Wipe them thoroughly with a dilute disinfectant such as jik, alcohol or heat them up in a fire," added Arinaitwe.
The commissioner for crop protection in the Ministry of Agriculture, Komayombi Bulegeya, said 85% of banana farmers know how to control the spread of the banana wilt disease and 30% of the farmers are aware of effective control of the disease. The government is however working towards introducing a new banana variety which is resistant to the wilt and this is still under experimentation.
Currently, genetically engineered crop species are undergoing field trial including cassava and banana. Dr. Arinaitwe said that in addition to guarding against the wilt, the new banana specie under field trial at the agriculture institute will be bio-fortified with a component that protects the crop against quick ripening. Cassava brown streak resistant specie is being developed and still under confined field trail at National Crops Resources Research Institute (NACRRI).
In Mukono, the government in a bid to counter the disease's effects has also introduced mobile plant clinics being operated by plant doctors.
"With mobile clinics, farmers are asked to take plant samples to the doctors for diagnosis who in turn interact with farmers and give them appropriate advice," said Anguzu.