Minding the gaps:
The quiet rise of the mighty mungbean

– 8 April 2026 –

In the rice fields of South and Southeast Asia, a quiet agricultural shift has been unfolding over decades. During the once-fallow periods between seasons, some farmers are planting mungbean – a fast-growing legume that matures in little more than two months – perfectly suited to fill the gap.

Mungbean’s protein-rich seeds provide valuable nutrition, while the plant itself fixes nitrogen to improve soil fertility. So, as well as filling the gap, it strengthens the farming system too.

This steady adoption of mungbean as a rotation crop has been driven by decades of plant breeding and collaboration led by the World Vegetable Center (WorldVeg) with national partners and both long-term and project support from the Australian Centre for International Agricultural Research (ACIAR). That work has addressed a particular challenge: closing the yield gap – the difference between what mungbean is capable of producing and what farmers typically harvest under real-world conditions shaped by heat, pests and disease.

Over the past five decades, this effort has produced more than 150 improved mungbean varieties that are typically high-yielding, early maturing and resistant to major diseases. Researchers have drawn on mungbean samples conserved in the WorldVeg genebank – the largest public repository of vegetable germplasm globally, which houses one of the world’s largest mungbean collections.

These improved varieties are now grown in 35 countries, covering an estimated 9 million hectares, helping transform mungbean from a marginal, semi-domesticated crop into one of the world’s most important grain legumes. WorldVeg varieties are grown by more than 1.2 million smallholder farmers in South Asia alone – usually in rice-based farming systems.

Adoption studies from 13 countries suggest these varieties now account for roughly one-third of the mungbean grown there, benefiting an estimated 1.7 million farmers each year. The economic returns have been striking too: studies from Myanmar – the world’s largest producer alongside India – estimate US$1.4 billion in gains between 1980 and 2016, projected to reach US$3.7 billion by 2030 – equivalent to about US$181 in benefits for every dollar invested.

The network effect

Building on these mungbean milestones has been the focus of the International Mungbean Improvement Network (IMIN). Established in 2016 with support from ACIAR and led by WorldVeg, IMIN brought together partners from Asia (Bangladesh. India, Myanmar and Indonesia) and Africa (Kenya). The network has steadily developed links with partners in other countries and developed into a larger network. The initiative strengthens collaboration among researchers, shares mungbean genetic resources and applies modern breeding technologies to expand mungbean cultivation, further close the yield gap, increase farmer incomes and improve nutrition. The extended network now covers 23 organizations across 20 countries.

IMIN supports multilocation trials of diverse mungbean breeding lines, testing promising materials across different environments to assess their performance and potential. The network also shares genetic markers for the crop – tools that allow breeders to more efficiently identify mungbean types that carry desirable traits – helping accelerate the development and release of improved varieties.

Recent IMIN successes include the release of two improved mungbean varieties in Tanzania: TARI-G-GRAM 4 and TARI-G-GRAM 5 for semi-arid regions of the country. Through IMIN, WorldVeg developed and shared advanced breeding lines, later tested by TARI and other partners.

The new varieties mature in 65–74 days, reducing time to harvest by one to two weeks compared with common local varieties. They also yield more than one tonne per hectare – around 10–15% higher than local commercial types. Importantly, the varieties have enhanced micronutrient content. TARI-G-GRAM 4 contains around 17% more iron and TARI-G-GRAM 5 around 6% more iron than current varieties, with both also providing about 3% more zinc. Moving forward, grain traders, processors and seed companies are expected to play a role in scaling up adoption.

Small beans, growing reach

Mungbean improvement is also expanding in West Africa. In Mali, Coprosem, a seed company, tested improved mungbean lines developed by WorldVeg and made available through the Africa Vegetable Breeding Consortium. This led to the release of two new varieties, KOBAS and HABAS, in 2025, for use as a main crop. These mature in about 50 days under Sahelian conditions and produce dark-colored grains preferred in local markets. An NGO supporting women farmers has begun distributing the seeds, with harvests supplying school canteens and food programs for internally displaced people.

The reach of WorldVeg breeding material is also evident in Australia, where mungbean is a high-value export crop, typically grown after winter wheat or barley. In 2025, the Queensland Department of Primary Industries released two new varieties, Brolga and Kookaburra. Brolga is widely adapted to Australian growing regions and produces seeds about 8% larger than Jade-AU, the country’s most widely sown variety. Kookaburra is the first region-specific mungbean variety bred in Australia, combining resistance to halo blight, tan spot and powdery mildew. The great-grandparents of both varieties trace back to WorldVeg.

Clockwise from top left: MSC student Ms. Hemanthsadhana N, from Tamil Nadu Agricultural University, India examining the roots of mungbean plants as part of her research into dry root rot; Farmers in Tanzania inspect improved mungbean lines released in the country; The release of the new mungbean varieties, Kookaburra and Brolga, in Australia.

Breeding for resilience – while building capacity

Despite these successes, important frontiers remain. At the WorldVeg South and Central Asia office in Hyderabad, India, postgraduate researchers are studying challenges such as dry root rot (DRR), caused by the fungal pathogen Macrophomina phaseolina, and post-harvest losses.

Using an approach known as QTL-seq (quantitative trait locus mapping combined with genome sequencing), researchers crossed a disease-resistant plant with a susceptible one to generate 310 genetically distinct lines. Grown in infected soil under greenhouse conditions, these lines allowed the team to identify genomic regions associated with resistance. The integration of QTL-seq into mungbean improvement programs holds strong potential for developing DRR-resistant varieties, thereby ensuring stable yields and enhancing resilience under climate change scenarios.

Another major constraint is pulse beetles, or bruchids (Callosobruchus species), storage pests whose larvae develop inside mungbean grain, hollowing it out and rendering it unfit for consumption or planting. Researchers identified one mungbean wild relative as strongly resistant to three major bruchid species, underscoring the importance of conserving wild plant genetic resources and their value to future breeding programs.

Taken together, this work is gradually reshaping how farmers use the short breaks in the cropping calendar. In many cereal-based systems, the weeks between harvest and planting once meant idle fields; today those gaps are increasingly filled with mungbean. It means that a crop once considered marginal is now helping farmers improve soils, diversify incomes and strengthen the productivity of the systems it fits into. Those once-overlooked gaps, it seems, are beginning to earn their keep.