By Prossy Nandudu & Jessica Nabukalu.
Uganda, Rwanda and Burundi are currently battling the mango mealybug. The bug sucks sap from the leaves of the mango tree, branches, leaves and fruits. In the process of feeding, it produces droppings which make the leaves black and sticky.
This lowers the strength of the tree, and its capacity to fruit. Symptoms of a plant that has been infested with the pest include sticky honey dew on leaves and stems, ants running about on leaves and stem among others.
The pest causes up to 100% yield loss because the sticky -waxy covering substance prevent pesticide from getting to the pest to kill it. This affects income earnings by farmers in mango growing areas, who earn from the sale of mangoes, and also fruit processing industries among others, according to the National Agriculture Research Organization (NARO).
While the use of pesticides to spray the affected plants could generate relief, its costly in terms of cost of pesticides, and labor.
Besides, continuous use of pesticides has lasting effects on the environment as the chemicals affect life in the soil and water sources.
Organisms in the soil that are affected by pesticides include the earthworms, that help in breaking down plant residues, to form manure but also create aeration in the soil, while in water fish species are usually affected but also livestock and humans who at some point drink the water among others, adds soil scientists from NARO.
In Uganda, the wasp was introduced to affected villages around Ntungamo district, around Mirama village on the Uganda/ Rwanda border to manage the pests.
That is why experts from EAC and IGAD, are calling for the use of biological control measures in managing pests.
Officiating at the three-day meeting at Sheraton Kampala Hotel on Tuesday, David Phiri the Sub Regional Coordinator for Eastern Africa and FAO Representative to the African Union, said that the persistent or recurrent threat of pests of plants continues to pose challenges to efforts promoting sustainable food production.
Adding that continued reliance on conventional methods of pest management such as the use of chemical pesticides has proved to be insufficient for prolonged suppression of pest problems.
“These makes it imperative that we seek alternatives that are environment friendly and do not pose risks to human health. Achieving this primarily requires the adoption of biological control and bio pesticides in agricultural production to harness the power of nature itself to manage pests of plants,” said Phiri.
At the same event, Dr Charles Owach, deputy director FAO in charge of Uganda programs added that outbreaks from endemic pests and invasion by transboundary pests like desert locust fall army worm, African army worm, have compelled farmers to procure and use inorganic pesticides. He however warned that while synthetic chemical pesticides have a role in agriculture, their use must be rationally based on a sound scientific basis.
“So embracing ecological approaches to pest management is crucial to enhancing food security and nutrition as well as safeguarding environmental and human health. This can be possible if we embrace biological control and bio pesticides to effectively manage plant pests for sustainable agricultural production,” Owach added.
However, for the control measures to be embraced, there is need for collaborations and awareness creation starting from scientists and research organizations in charge of the biological control measures, added Kenneth Mwangi from IGAD’s climate mitigation and adaptation center.
Although the control measures could help countries manage emerging pests like desert locusts and fall army worm, some countries still lack regulations when it comes to importing biological control measures that could be plants or insects like the wasp, added Mwangi.
“To address the fears, Mwangi said that IGAD, plans to engage experts to help in the monitoring IGAD will be monitoring all these, support countries to have regulations in place, monitor control measures in a particular control, conducted joint researchers to address the challenge,” added Mwangi.
Other challenges hindering the uptake of biological control measure include lack of information about potential biological control measures, infrastructure like laboratories among others.
Other biological interventions in Uganda
Management of the water hyacinth in the early 1990s on Lake Victoria, Diamondback-moth, a pest of cabbages, Cassava mealybug, the cassava green mites, Salvinia molesta, and the Maize stem borers (locally called Ndiwulira,) among others.
