The Iron giants of Tanzania:
New mungbeans promise faster harvests and improved nutrition

– 30 October 2025 –

Tanzanian farmers are set to benefit from two new mungbean varieties that combine drought tolerance, high yields, and a much-needed nutritional punch. Recently released by the Tanzania Agricultural Research Institute (TARI), TARI-G-GRAM 4 and TARI-G-GRAM 5 are designed for the country’s semi-arid areas, where farmers depend on crops that thrive under dry conditions.

Mungbean – also known as green gram – may not rival maize or rice in terms of popularity, but researchers see it as a crop of the future in Africa. It grows quickly, tolerates dry conditions, and enriches the soil by fixing nitrogen, reducing the need for chemical fertilizer. Nutritionally, mungbean is also rich in protein, iron, and zinc – nutrients often missing in rural diets, particularly for children and women. In East Africa, where anemia rates remain high and droughts regularly disrupt food supplies, a hardy crop that can deliver both nutrition and income is especially valuable.

The newly released varieties – intended for Tanzania’s Dodoma, Singida, Tabora, Mwanza and Simiyu regions – mature in just 65–74 days, shaving between one and two weeks off the normal time to harvest, helping farmers avoid late-season heat and water stress. They also yield over one ton per hectare – between 10-15% more than local, commercial varieties. TARI-G-GRAM 4 also contains around 17% more iron, and TARI-G-GRAM 5 around 6% more iron than locally available types. Both varieties also provide around 3% more zinc, another critical nutrient often missing from local diets.

TARI-G-GRAM 4

TARI-G-GRAM 5

Breeding mungbeans for better health

The release represents the latest achievement of the Mung4Fe project – funded by the African Union Commission and the European Commission – which works to combat malnutrition in drought-prone areas of East Africa by developing iron-rich mungbeans. The project was led by Uganda’s National Agricultural Research Organization (NARO), in collaboration with TARI, the Kenya Agricultural and Livestock Research Organization (KALRO), and the World Vegetable Center (WorldVeg). Through the International Mungbean Improvement Network (IMIN) – a global partnership supported by the Australian Centre for International Agricultural Research (ACIAR) – WorldVeg developed and shared advanced mungbean breeding lines. These were further tested by TARI and other partners.

The release of the two varieties follows a four-year period of on-farm trials, from Moshi in the northeast, to Dodoma in the country’s semi-arid central interior, as well as Morogoro in the east and Mwanza in the northwest. Farmers took part in the evaluation process, helping to identify the most preferred varieties.

“Mungbean has huge potential to improve food production, soils, and diets in Africa,” said Ram Nair, Global Plant Breeder – Legumes, at WorldVeg. “These two releases represent crop breeding at its best – combining multiple useful traits into two powerful pulses that farmers themselves helped us select.”

From trials to release

After evaluation of WorldVeg’s elite mungbean breeding lines, the best candidates entered Tanzania’s national performance trials in 2022-24. Tests across multiple agroecological conditions confirmed strong performance even under low and unreliable rainfall, with mean annual precipitation as low as 500 mm.

By July 2025, the varieties had met regulatory standards and were officially approved for release. During the process, 345 farmers were reached directly, and 86 kilograms of seed was produced for wider planting. With support from Tanzania’s Ministry of Agriculture under the Tanzania Food System Resilient Program (TFSRP), seeds of these varieties are expected to reach over 800 farmers in the 2025/2026 cropping season.

“It’s particularly exciting to see these iron-enriched mungbeans reach the field after years of work,” said Papias Binagwa, Senior Research Officer and Legume Breeder at TARI. “They’ll quickly provide a protein- and micronutrient-rich food source for communities and help combat malnutrition in semi-arid regions.”

The benefits of the new mungbeans extend to grain traders, processors, and seed companies, who are expected to play a role in scaling up adoption. With their short maturity, it is hoped the varieties can fit neatly into existing cropping systems, offering farmers an extra harvest in a single season.

With climate variability increasing and demand for healthy foods rising, TARI-G-GRAM 4 and 5 could help farmers produce more nutritious food, strengthen rural economies, and build resilience where it’s most needed.