Tanzania: Why Institutions Must Join Forces to Fight BBTD

IN the face of a growing threat to banana farming across East Africa, a coalition of research institutions, agricultural authorities and farming organisations in Tanzania is working tirelessly to contain the spread of Banana Bunchy Top Disease (BBTD) a devastating viral disease that threatens one of the region’s most critical food and income sources.

Leading this collaborative effort are the International Institute of Tropical Agriculture (IITA), the Tanzania Agricultural Research Institute (TARI) and the Tanzania Plant Health and Pesticides Authority (TPHPA), these organisations are combining their expertise in scientific research, seed systems, plant health surveillance and farmer training to combat the disease through both traditional and modern methods.

The disease at a glance

BBTD is caused by the Banana Bunchy Top Virus (BBTV) and is spread by a small insect known as the banana aphid (Pentalonia nigronervosa), Tanzanian farmers called ‘fungashaba ya migomba’. “The insects live around the neck of the banana plant and transmit the virus from infected to healthy plants, ” says Gloriana Ndibalema, Communications Officer at IITA.

“But with the right practices, including improved seed varieties and proper field management, it can be controlled.” Ms Fatma Mussa, a researcher at IITA said the disease has no chemical cure since it was first discovered in Tanzania in 2020 in Buhigwe District, Kigoma Region. Since then, it has spread rapidly to several other regions including Mbeya, Kilimanjaro, Dar es Salaam, Pwani, Morogoro, Dodoma and Mwanza.

“The disease can cause between 90 per cent and 100 per cent yield loss in a single season,” Ms Mussa warns. “Once it infects a field, farmers lose both income and food security and the recovery process is expensive and time-consuming.”

Devastating effects and signs

BBTD does not discriminate against banana types it affects all varieties. Infected plants display stunted growth, tightly bunched leaves that resemble a flower bouquet and spear-shaped yellowing leaves. If infected before flowering, the banana plant fails to produce fruit altogether.

To limit the spread, experts urge farmers not to move infected planting materials across regions and to avoid using suckers from unknown sources. “Sometimes some farmers like to move planting seeds from one place to another, from one region to another, just because they saw a banana plant and liked it.

That is what mostly causes the spread of diseases and their rapid transmission,” Ms Mussa stressed. Fatma outlines several approaches for managing the disease: Traditional methods: Regular field inspection, uprooting infected plants from the roots, chopping them into small pieces, burning or burying the remains and monitoring for regrowth. Scientific methods: Injecting herbicide directly into infected banana stems.

Fatma recommends mixing herbicide with water and injecting the solution into the plant using a large syringe at specific points depending on the weeks later, once completely dead. These interventions aim to kill the infected banana plants completely and reduce the chances of re-infestation.

Seed innovation as a sustainable solution

TARI and IITA’s long-term partnership have been instrumental in breeding and releasing improved banana varieties TARIBAN 1 through 4 that are resilient and yield more fruit. The institutions are also behind the development of over 15 improved cassava varieties such as TARICASS 1 to 9.

Director of TARI from Maruku Centre in Kagera, Dr Mpoki Shemwela said the varieties offer better resistance to diseases and suit different agro-climatic conditions “Our work ensures that these seeds reach farmers quickly and effectively,” said Dr Shimwela. This joint effort extends beyond crop development.

Both institutions have conducted virus surveillance and trained extension officers and farmers on early detection and control of BBTV. He said since the disease was officially identified in 2021, they worked hand by hand to curb its spread.

Safeguarding plant health through policy and monitoring

The TPHPA Principal Agricultural Officer National BBTV Management Coordinator, Mr Hamad Lyimo emphasises the authority’s role in monitoring plant health nationwide.

The agency enforces regulations governing the movement of plant materials and collaborates with international partners on disease diagnostics and surveillance. “We are committed to ensuring that any threat to plant health, including banana diseases, is addressed swiftly through science and policy,” he says

A model of regional cooperation East

Africa’s banana sector faces a shared challenge in BBTD, and Tanzania’s model of institutional collaboration offers hope. Through joint research, seed innovation, community education and strict phytosanitary controls, the battle against this silent crop killer is being fought on multiple fronts.

IITA Communication Officer, Ms Gloriana Ndibalema said the institute has been training agricultural officers and farmers in surveillance, sanitation (roguing) and eradication methods and is supporting efforts to map the disease and distribute clean planting materials.

“We urge farmers to follow the advice of our agricultural officers to ensure productive banana farming. In collaboration with both local and international stakeholders, the institution has secured new, improved banana seedlings. Therefore, there is no reason to continue using old, disease-prone varieties.

By adopting these new seedlings, farmers will achieve better yields and improved produce,” said Ms Ndibalema. Noting: “Science alone is not enough, what makes the real difference is when science meets the field, when we work with farmers and when we all take responsibility to protect our crops.”

By Daily News.