Regeneration of biological resources from the tropical BRC in Montpellier, France S. Vancoppenolle © CIRAD

Sorghum and millet

Thanks to their plasticity and wide range of forms (phenotypes), sorghum and millet can be integrated into many cropping systems in tropical and temperate zones. These cereals are vital food crops for vulnerable people in arid and semi-arid tropical regions. Their specificities in terms of adaptation to their environment and of their grain quality allow them to satisfy the particular requirements of such zones, while their capacity to provide numerous ecosystem services make them crops of the future. Some 20 CIRAD researchers are involved in research on these two species. Their work covers every aspect of the value chains, from designing sustainable, input-saving cropping systems to creating and disseminating new varieties better suited to current and future environmental constraints and market demand.

The figures for sorghum

5th cereal grown worldwide (in terms of grain production and area planted).
Total output estimated at 60 million tonnes (Mt) per year, on a total area of 41.8 million hectares (Mha) over the period 2010-2022.
In terms of output, the US is well ahead of the pack (9.34 Mt), followed by Nigeria (6,61), Mexico (5.68), India (5,49), and Sudan (5.18).
In terms of area planted, the three leading producing countries are Sudan (6,75 Mha), India (5.64), and Nigeria (5,5).
Sorghum is a staple in the diet of more than 300 million people in semi-arid tropical zones.

The figures for millet

There are many species classed as "millet". The main one in terms of production worldwide is pearl millet (Cenchrus americanus, also called Pennisetum glaucum), which is the main target of CIRAD's research.
6th cereal grown worldwide (in terms of grain production and area planted).
Total output estimated at 29.2 Mt per year, on a total area of 31.7 Mha over the period 2010-2022.
In terms of output, India tops the rankings (11.55 Mt), followed by Niger (3.4) and Nigeria (2). 
In terms of area planted, the three leading producing countries are India (9.5 Mha), Niger (6.92 Mha) and Sudan (2.76 Mha). 
Millet is a staple in the diet of more than 90 million people in semi-arid tropical zones.

Two species with multiple uses

Grain to feed people (porridge, couscous, biscuits, breadmaking, fermented drinks…) and animals
High food-value fodder in various forms (green, hay or silage)
Cover crop to conserve soils and remobilize minerals within DMC systems
Sorghum and millet are also plants with a strong social, cultural and symbolic value in many African countries
Uses specific to sorghum:
- Soluble sugars can be extracted from sweet sorghum varieties to make syrups, ethanol, 1st-generation fuel ethanol or alcohol/spirits
- Lignocellulosic biomass to generate energy via methanization, thermal plants and 2nd-generation fuel ethanol production, and to make construction materials ( composite plastics or building blocks, etc)
- Various low-, medium- and high-added-value molecules for agro-industry: tannins, anthocyanins (pigments), kafirins, aconitic acid, etc.

The issues for sorghum and millet

Shared issues in semi-arid tropical regions

Making the crops substantially more competitive in areas where cereal crop intensification is under way.
Exploiting the potential of sorghum and millet better to contribute to the fight against malnutrition and certain chronic diseases (eg diabetes).
Making production more consistent by maintaining good grain quality.
Diversifying food use to boost producer incomes and create jobs in rural areas.
Promoting and developing food and non-food use of multi-purpose sorghums and millets.
Making better use of these species' potential to contribute to agroecological intensification as a pest and disease regulators.
Integrate these crops better into production systems, to boost their resilience.

Issues specific to sorghum in France and Europe

While sorghum currently accounts for a limited area in Europe (0.3 Mha), it could be of interest for diversifying rotations and helping to adapt European farming to climate change. The main challenges specifically identified for this geographical zone are:
- Developing products for human consumption and varieties to help support such specific value chains.
- Developing varieties and crop management sequences and building stakeholder networks for biomass recycling chains: animal feed, energy, construction.
- Making use of sorghum's potential to provide ecosystem services (soil detoxification or stabilization, boosting pollinator populations, etc).