Chapter 5.15
5.15 -Pearl millet to mitigate climate change
David Rether, University of Guelph, Canada
Suggested citation for this chapter.
Rether,D. (2022) Pearl millet to mitigate climate change, In Farmpedia, The Encyclopedia for Small Scale Farmers. Editor, M.N. Raizada, University of Guelph, Canada. http://www.farmpedia.org
Introduction
Climate change is gradually becoming a production constraint on agriculture worldwide. Both commercial and subsistence farmers feel the struggles cast upon them due to climate change; increasing temperatures are impacting growing conditions which means farmers must improvise and adapt. The purpose of this report is to examine if pearl millet (Pennisetum glaucum) can be utilized by subsistence farmers in Africa and India to combat areas that suffer from drought to ensure that farmers and their families can supply themselves with food and an income.
Crop Information
Location
The origin of pearl millet is the tropical region of western Africa from over 4000 years ago (Myers, 1999). Pearl millet has 32 landraces in total (Ragupathy, 2016). Some of the well known landraces of millet include foxtail, common, and finger tail (Kajuna, 2001). Pearl Millet is grown today by subsistence farmers in West Africa and India, and is also used as a forage and grain crop which is eventually processed into poultry feed and cattle feed. Bird seed is also produced from pearl millet in developed countries such as the USA (Myers, 1999). The International Crop Research Institute for the Semi Arid Tropics (ICRISAT) has a seedbanks for pearl millet with additional seedbanks in in India, Kenya, Malawi, Zimbabwe, Mozambique, Ethiopia, Mali, Niger, and Nigeria. Pearl millet is the most major millet grown in Africa and is the fourth most important cereal crop grown in India (Kajuna, 2001).
Pearl Millet Growing Conditions and Plant Characteristics
Pearl Millet is more drought tolerant than sorghum and can grow well on sandy soils (Kajuna, 2001). (Pearl millet takes anywhere from 80-100 days to mature. Many subsistence farmers do not have the capacity to irrigate their crops. Even without irrigation, pearl millet can produce a beneficial yield with annual rainfall as low as 150 mm per year (NRC, 1996). Pearl millet is usually a short-day plant. Pearl millet prefers seasonal rainfall between 200-1500 mm, but can still produce with less. Unlike pearl millet’s close substitute, sorghum, pearl millet does not have the ability to enter dormancy. This is an issue as this means the precipitation distribution must be even throughout the 100 day growing season (NRC, 1996). A significant drought during a short period of time during the flowering point of plant maturity will result in the crop to fail (NRC, 1996). Pearl millet grows best in light, well-drained loams. Pearl millet does not perform well in clays due to its inability to tolerate excessive amounts of water. Pearl Millet can tolerate soils that have pH levels as low as 4-5 and have high aluminum content. (NRC, 1996). High daylight temperatures are required for pearl millet to mature; daily highs must exceed 30 degrees Celsius. In Africa and India, access to fertilizer is not simple nor feasible for subsistence farmers. Yields are so low in Africa and India, even a crop such as pearl millet can only grow approximately 500 kg of grain per hectare; approximately 8 times less than an irrigated crop will yield (NRC, 1996). Even though pearl millet can produce low yields, some famers prefer to grow it over other cereal crops because it can germinate in high temperature soils, crusted soils, tolerate wind and sedimentary damage, resist downy mildew, and have above average pest tolerance. (NRC, 1996). Finding synthetic fertilizer that is affordable can be very difficult, so it is important for subsistence farmers to incorporate other methods, such as nitrogen fixing trees, plants, or biological nitrogen such as animal and human manure. If synthetic fertilizer is used, apply 200 kg of NPK per hectare immediately after seeding. This should then be followed by 50 kg per hectare of urea. Weeding must be done before the crop is planted to help with germination and cropping methods can be used to minimize weeds such as intercropping.
Plant Nutrition, By-Product and Human Consumption
Nutrition
Pearl millet is a very nutritious grain that can be consumed by humans and be transformed into other foods. Per 100 grams of pearl millet consumed, it has; 11.8 grams (g) of protein, 4.8 g of fat, 2.2 g of ash, 2.3 g of crude fibre, 67 g of carbohydrate, 363 energy (kcal), 42 mg of calcium, 11 mg of iron, 0.38 mg of thiamin, 0.21 mg of riboflavin, and 2.8 mg of niacin (FAO, 1995). These are very important to take note of as pearl millet provides the most energy per 100 g in comparison to other Sub-Sahelian millets, the 2nd from best iron content, 2nd from best riboflavin, the most protein, and the second from highest amount of fat (Sorghum and millets in human nutrition, 1995). Pearl millet also contains several essential amino acids such as; cysteine (1.8 mg/g), isoleucine (3.9 mg/g), leucine (9.5 mg/g), lysine (3.2 mg/g), methionine (1.8 mg/g), phenylalanine (4.1 mg/g), threonine (3.3 mg/g), tryptophan (1.4 mg/g), tyrosine (3.0 mg/g), and valine (4.9 mg/g) (NRC, 1996).
Human Consumption
Pearl millet is often processed by women and children to make porridge. The grain from pearl millet is used and processed as whole, cracked, or ground flour and transformed into rice, breads such as roti, kisra and gallettes, couscous, beer, and snacks. (NRC, 1996).
By-Products
The pearl millet plant yields roughly 80% stalk and 20% grain. The stalks of pearl millet can be utilized as housing and fencing supplies, as well as fuel. (NRC, 1996). As well as supplies for the farmer and family, stalks of pearl millet can also be re-used as feed for ruminating animals, such as cattle, goats, and sheep (Gupta, Ghouse, Atkari, & Blummel, 2015). This is an excellent method to maximize the efficiency of a subsistence farm, as the animals fed on pearl millet stover can subsequently be fed to the family after reaching maturity.
Subsistence Farming of Pearl Millet
Pre-Harvest Operations
No additional equipment is required for seeding. The required rate to plant is 4kg per hectare (FAO, 2018). Ridges should be spaced out 75-90 cm apart. Planting must occur after 25mm of rain has occurred, to ensure proper germination. Seeds will germinate after 5 days if the seeds are good (FAO, 2018). The ridge must be 2.5cm deep, and 5 seeds must be placed together every 40 cm (FAO, 2018). Common pests of pearl millet include birds. In terms of disease, the plant is prone to is downy mildew, as well as the weed Eleucine indica, which can be better tolerated through early planting (FAO, 2018).
Post Harvest Operations
Harvesting pearl millet can be difficult and time consuming as the crop often ripens at different points. This requires that harvesting be done in stages to ensure the grain head does not shatter in the field (Kajuna, 2001). Harvesting is done by the women and children of the farm. The grain heads are removed by removing the ear with approximately 2cm of stalk (Kajuna, 2001). The plants are then transported back to the farm. Transportation can either be done by hand, or by incorporating the use of a large animal (donkey, cow) and a wagon to transport more grain at once ( (Kajuna, 2001). The plants and loaded onto either a donkey, or a trailer, and carried back to the farm. Once arriving at the farm the grain can be easily dried as it is a small grain. The grain is tsun-dried by placing the grain on a table and the farmer must wait a few days for it to dry to achieve the desired taste (Kajuna, 2001). Once dried, threshing beings. Threshing is difficult as it requires the grain to be beaten from the heads using mats and clubs. The grain must then be bagged (Kajuna, 2001). The remaining stalks are then used for fuel and animal feed. The seed must then be cleaned of sand, gravel, dirt and other germs. The only tools required to complete this entire harvest process are sharp knives that are handheld. Additional drying equipment may be purchased, but that is often not an economical choice for a subsistence farmer. The cleaning of pearl millet is time consuming as it takes up to 1 hour to clean a 100kg bag (Kajuna, 2001). Storage of crops is done in hessian/sisal bags of up to 100kg, and then taken to the market, or into storage (Kajuna, 2001).
Critical Analysis of Adopting Pearl Millet
Pearl Millet is a crop that can be easily adopted by subsistence farmers as no additional equipment is required. The seeds are readily available to farmer organizations and governments from seedbanks such as ICRISAT. Pearl millet is a plant that should be focused on to combat drought, as it performs much better than plants such as sorghum and other types of millet. Pearl millet has many uses as the grain can be transformed into many different foods for human consumption. The leaves of the plant are perfect for animal consumption which in turn can be further used for transportation, farm labor, food and clothing. The large stalks of the pearl millet plant are perfect for structural use, such as fencing, roofing, and general house building supplies. Pearl millet can grow with or without the use of synthetic fertilizers. It is very rich in nutrients and essential amino acids and is more nutritious than other millets and plants such as sorghum. In conclusion, there is an opportunity for more subsistence farmers in Africa and India to adopt pearl millet to combat drought, as it is more tolerant to dry conditions, is higher in nutrition, and its by-products have many more uses than any other substitutes available.
Despite these benefits, the adaption of pearl millet also introduces complications as it is labor intensive for the women and children that are primarily responsible for farm operations. Another complication of growing pearl millet is that the irrigation must be evenly distributed as the pearl millet seed is not able to reach into dormancy, unlike sorghum which is a close substitute to pearl millet. Millet is also a challenging crop to consume due to the intense process of grain threshing. Special tools can be purchased to ease this process but are often expensive and hence unfeasible for smallholders. Pearl millet can suffer from significant yield decline if the rain season is not evenly distributed. An average yield for pearl millet can range from 500-1500 kg per hectare, but, if precipitation is not evenly distributed through the 100 day growing season yields can deteriorate to as low as 150 kg per hectare. Economic reports from ICRISAT suggest that pearl millet costs the least to produce in comparison to sorghum and maize and hence more profitable to smallholders (Tsusaka, 2015).
2018).Helpful resources to get started
https://www.youtube.com/watch?v=azOv72vOsdA Threshing pearl millet using modern threshing tools to remove grain from stem.
http://agropedia.iitk.ac.in/content/harvesting-and-storage-pearl-millet Webpage containing step-by-step information regarding harvesting steps of pearl millet
http://southafrica.co.za/how-to-grow-pearl-millet.html Webpage containing information regarding proper time to harvest pearl millet and how to harvest pearl millet
https://www.organic-africa.net/fileadmin/documents-africamanual/training-manual/chapter-09/Africa_Manual_M09-03.pdf Detailed webpage regarding information about complications, and directions on growing and harvesting millet.
https://cookpad.com/us/search/pearl%20millet 85 pearl millet recipes in cooking manual
https://www.youtube.com/watch?v=P5yLjVBhu_E 10 minute video about cooking pearl millet porridge in an African village
https://www.youtube.com/watch?v=jB6dmU3OYJs Pearl Millet is even being used as an ornamental crop in developed countries.
https://pdfs.semanticscholar.org/fc85/d688aaa3c6a2f130c078479b2b6151f1eb51.pdf Economic report from the ICRISAT, sorghum, maize, and pearl millet are analyzed on a profitability index from production in Marara.
References
1. Burgarella. (2019). A western Sahara centre of domestication inferred from pearl millet genomes. Nature Ecology and Evolution, 2, 1377-1380. Retrieved from https://www.nature.com/articles/s41559-018-0643-y.pdf
2. FAO (1995). Sorghum and Millets in Human Nutrition No. 27, (p. Chapter 11). Rome: David Lubin Memorial Library Cataloguing in Publication Data.
3. FAO. (2018). Seed production and handling manual for community based seed inspectors and producers. FAO, Rome, 2-48. Retrieved from http://www.fao.org/3/ca1082en/CA1082EN.pdf
4. Food, F. M. (2017, June 17). Real Village Food / Cooking Pearl Millet - Horse Gram Recipe in My Village. Retrieved from https://www.youtube.com/watch?v=hCwzPNuqAwA
5. Gupta, S., Ghouse, S., Atkari, D., & Blummel, M. (2015). Pearl millet with higher stover yield and better forage quality: Identification of new germplasm and cultivars. CGIAR, 1. Retrieved from https://cgspace.cgiar.org/handle/10568/73393
6. Kajuna, S. T. (2001). MILLET: Post-harvest Operations. INPhO Post-harvest Compendium, 1-48. Retrieved from http://www.fao.org/fileadmin/user_upload/inpho/docs/Post_Harvest_Compendium_-_MILLET.pdf
7. Myers, R. (1999). Pearl Millet: A New Grain Crop Option for Sandy Soils or Other Moisture Limited Conditions. New Crops Resource Online Program, Columbia, MO: Jefferson University. Retrieved from https://www.extension.iastate.edu/alternativeag/cropproduction/pdf/pearlmillet_crop_guide.pdf
8. NRC. (1996). Lost Crops of Africa Volume 1. In NRC, Pearl Millet, National Research Council, Washington, DC: The National Academies Press (pp. 77-110). Retrieved from https://doi.org/10.17226/2305
9. Ragupathy. (2016). DNA record of some traditional small millet landraces in India. 3 Biotech 6, 33. Retrieved from https://link.springer.com/article/10.1007%2Fs13205-016-0450-6
10. Tsusaka. (2015). Sorghum in Semi-arid Subsistence. Socioeconomics Discussion Paper Series, 20-24. Retrieved From https://pdfs.semanticscholar.org/fc85/d688aaa3c6a2f130c078479b2b6151f1eb51.pdf