New study on pearl millet unveils opportunities for climate-resilient feed and forage

Pearl millet (Cenchrus americanus) is a staple crop that provides food for roughly 90 million people across sub-Saharan Africa’s arid and semi-arid regions. This hardy plant belongs to the millet family, a highly adaptable grain that can grow in harsh climatic conditions. India is the largest pearl millet producer, closely followed by Nigeria, Niger and China. In addition to its grain, the leaves of the pearl millet plant are high in energy, calcium, iron and high-quality protein, making them an ideal feed option for livestock.

In a recent study titled, ‘Pangenomic analysis identifies structural variation associated with heat tolerance in pearl millet’, researchers from the Sichuan Agricultural University, China, in collaboration with the International Livestock Research Institute, utilized genomic tools to unveil new opportunities for developing improved varieties of pearl millet.

‘What's key about this study is that it paves the way for breeders in Africa to enhance pearl millet’s resilience to heat and drought, crucial traits as we face escalating temperatures and erratic rainfall patterns,’ said Chris Jones, who leads the Feed and Forage Development program at ILRI and is an author in the study.

The study employed a pangenome analysis, allowing scientists to read the complete set of genes in pearl millet and explore its genetic diversity. In addition, by selecting specific genomes from different geographical regions with varying climatic conditions for the pangenome analysis, researchers were also able to identify the key genes and structural variations associated with heat tolerance and drought resistance.

Jones also highlighted the importance of international collaboration in ongoing pearl millet research. ‘Such collaborations allow scientists to expedite the development of climate-resilient varieties more efficiently,’ said Jones.

Pearl millet developed in south Asia has already been successfully adapted to east Africa and serves as a testament to the potential of these collaborative efforts. Through further exploration and research, there is an opportunity to introduce pearl millet as a cash crop and integrate it into existing value chains, thereby creating additional income sources for farmers.

Future research

Jones also aims to contribute to the development of improved pearl millet varieties by conducting examinations in conjunction with elephant or Napier grass (Cenchrus purpureus), a popular forage in east Africa:

'Pearl millet is one of the progenitors–or precursors– of elephant grass. When pearl millet and its superior forage quality are crossed with the highly productive Napier grass, the resultant hybrids are highly regarded,' said Jones.

'I’m interested in better understanding the genomic differences between elephant grass and pearl millet accessions with high and low forage potential. Knowing these differences offers an important opportunity to improve the forage value of both of these crops.'

A year dedicated to millet

Did you know that 2023 has been designated as the International Year of Millets? Led by the UN Food and Agriculture Organization (FAO), this significant initiative aims to raise awareness and prioritize policy actions regarding the nutritional and health advantages of millets and their adaptability to adverse and shifting climate conditions.

ILRI is excited about this opportunity and intends to leverage the momentum of the newly released study on pearl millet and the International Year of Millets.  Based on past projects and studies focused on developing highly productive pearl millet varieties that can thrive in the face of rising temperatures, ILRI is committed to supporting farmers with resilient solutions. For further insights, you can explore the studies listed below:

1. Improving Quality of Pearl Millet Residues for Livestock: The project enhanced smallholder livestock production in arid and semi-arid regions of India by developing pearl millet hybrids with increased nutrition qualities. Following the project, an improved pearl millet variety was successfully transferred to Ethiopia.
2. Improved sorghum and pearl millet forage cultivars for intensifying dairy systems: The study identified and disseminated higher yield and better-quality sorghum and pearl millet forages derived from diverse genetic breeding pools to dairy producers while exploring the feasibility of forage production as a cash crop. Researchers recommended focusing on these water-use efficient and bio-physically robust pearl millet forages to mitigate drought and water scarcity risks. In addition, they addressed the issue of neglected selection for fodder quality and explored opportunities for forages-as-cash crops alongside their use as on-farm feed resources.
3. Genotypic Variation in Forage Linked Morphological and Biochemical Traits in Hybrid Parents of Pearl Millet: This study evaluated 116 pearl millet hybrid parents for forage-specific morphological and quality traits, recommending breeding modifications to develop more productive forage hybrids.
4. Utilization of Molecular Marker-Based Genetic Diversity Patterns in Hybrid Parents to Develop Better Forage Quality Multi-Cut Hybrids in Pearl Millet: This study investigated the genetic diversity of forage-type hybrid parents in pearl millet. The study suggested that using marker-based clustering patterns can select diverse parents for crossing, leading to the development of pearl millet hybrids with improved forage quantity and quality and the potential to predict forage traits using markers.
5. Understanding Heterosis, Genetic Effects, and Genome-Wide Associations for Forage Quantity and Quality Traits in Multi-Cut Pearl Millet: The study assessed multiple sets of pearl millet hybrids, revealing significant variability and potential for improvement in forage quantity and quality. Furthermore, the study identified superior parental lines for future breeding programs and also highlighted the potential use of marker-assisted selection for improved varieties. 
6. Comparative Evaluation of Sorghum and Pearl Millet Forage Silages with Maize: This study examined the quality of silage made from sorghum and pearl millet forage compared to maize, focusing on productivity and drought resistance. Scientists recommended cultivating pearl millet as forage in semi-arid and tropical regions as climate-resilient, drought-tolerant alternatives to maize.