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- Herausgeber: John Wiley & Sons
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- Sprache: Englisch
Millets and sorghum are extremely important crops in many developing nations and because of the ability of many of them to thrive in low-moisture situations they represent some exciting opportunities for further development to address the continuing and increasing impact of global temperature increase on the sustainability of the world’s food crops.
The main focus of this thorough new book is the potential for crop improvement through new and traditional methods, with the book’s main chapters covering the following crops: sorghum, pearl millet, finger millet, foxtail milet, proso millet, little millet, barnyard millet, kodo millet, tef and fonio. Further chapters cover pests and diseases, nutritional and industrial importance, novel tools for improvement, and seed systems in millets.
Millets and Sorghum provides full and comprehensive coverage of these crucially important crops, their biology, world status and potential for improvement, and is an essential purchase for crop and plant scientists, and food scientists and technologists throughout the developed and developing world. All libraries in universities and research establishment where biological and agricultural sciences are studied and taught should have copies of this important book on their shelves.
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Table of Contents
Cover
Title Page
Copyright
List of Contributors
Preface
Introduction
Origin and History of Sorghum and Millets
Millets – the Climate-Smart Crops
Millet Area and Production Statistics
Millets – Store Houses of Nutrition
Constraints for the Improvement of Millets
Scope for Future Improvement of Millets
References
Chapter 1: Sorghum, Sorghum bicolor (L.) Moench
1.1 Introduction
1.2 Origin and Taxonomy
1.3 Germplasm Resources and Utilisation
1.4 Genetics and Cytogenetics
1.5 Reproductive Biology
1.6 Production Constraints
1.7 Breeding Objectives
1.8 Sorghum Improvement Across Diverse Parts of the World
1.9 Future Prospects
References
Chapter 2: Pearl Millet, Pennisetum glaucum (L.) R. Br.
2.1 Introduction
2.2 Origin and Taxonomy
2.3 Genetic Resources
2.4 Genetics of Important Traits
2.5 Morphology and ReproductiveBiology
2.6 Selfing and Crossing
2.7 Breeding Methods
2.8 Cultivar Development
2.9 CMS Systems in Pearl Millet
2.10 Production Constraints
2.11 Grain Quality
2.12 Alternate Uses of Pearl Millet
2.13 Future Research Thrust Areas
References
Chapter 3: Improvement in Finger Millet: Status and Future Prospects
3.1 Introduction
3.2 Area Production and Productivity
3.3 Origin and Domestication
3.4 Botanical Features and Breeding Behaviour
3.5 Emasculation and Pollination Techniques
3.6 Genetics of Traits
3.7 Gene Pool of
Eleusine coracana
3.8 Germplasm and Genetic Diversity
3.9 Varietal Improvement in India
3.10 Varietal Development in Africa
3.11 Genetic Improvement for Blast Resistance
3.12 Development of Genetic Male Sterility
3.13 Mutation Breeding
3.14 Strategies to Bridge Research Gaps for Enhancing Productivity and Utilisation of Finger Millet
References
Chapter 4: Foxtail Millet, Setaria italica (L.) P. Beauv.
4.1 Introduction
4.2 Origin and Taxonomy
4.3 Germplasm Resources and Utilisation
4.4 Genetics and Cytogenetics
4.5 Reproductive Biology
4.6 Breeding Objectives
4.7 Breeding Methods
4.8 Breeding Efforts in the United States
4.9 Breeding Efforts in China
4.10 Breeding Efforts in India
4.11 New Tools for Genetic Improvement
4.12 Future Prospects
References
Chapter 5: Proso Millet, Panicum miliaceum (L.): Genetic Improvement and Research Needs
5.1 Introduction
5.2 Origin and Taxonomy
5.3 Botany and Reproductive Biology
5.4 Growth and Development
5.5 Cytogenetics
5.6 Genetic Resources and Utilisation
5.7 Genetic Improvement of Proso Millet: Achievements and Status
5.8 Breeding Objectives and Research Strategies
5.9 Future Prospects
References
Chapter 6: Genetic Improvement in Little Millet
6.1 Introduction
6.2 Floral Biology
6.3 Cytogenetics and Morphological Variation in the Genus
6.4 Improvement in Little Millet
6.5 Critical Research Gaps
6.6 Strategies for Genetic Improvement
References
Chapter 7: Barnyard Millet: Present Status and Future Thrust Areas
7.1 Introduction
7.2 Nutritional Composition and Food Value
7.3 Origin and Taxonomy
7.4 Reproductive Biology
7.5 Cytogenetics
7.6 Genetic Resources and Utilisation
7.7 Breeding Objectives
7.8 Future Prospects
References
Chapter 8: Kodo Millet, Paspalum scrobiculatum L.
8.1 Introduction
8.2 Origin and Taxonomy
8.3 Germplasm Resources and Utilisation
8.5 Genetics and Cytogenetics
8.6 Reproductive Biology
8.7 Breeding Objectives
8.8 Breeding Methods
8.9 New Tools for Genetic Improvement
8.10 Future Prospects
References
Chapter 9: Tef, Eragrostis tef (Zucc.) Trotter
9.1 Introduction
9.2 Origin and Taxonomy
9.3 Genetic Resources and Utilisation
9.4 Genetics and Cytogenetics
9.5 Reproductive Biology
9.6 Constraints in Tef Production
9.7 Genetic Improvement of Tef
9.8 Crop and Pest Management
9.9 Future Prospects
References
Chapter 10: Insect Pests of Millets and Their Host Plant Relations
10.1 Insect Pests
10.2 Host-Plant Selection by Insect Pests
References
Chapter 11: Millet Diseases: Current Status and Their Management
11.1 Introduction
11.2 Sorghum Diseases
11.3 Pearl Millet Diseases
11.4 Small Millet Diseases
References
Chapter 12: Nutritional Qualities & Value Addition of Millets
12.1 Introduction
12.2 Sorghum
12.3 Pearl Millet
12.4 Finger Millet
12.5 Other Millets
12.6 Health Benefits of Millets
12.7 Conclusion
References
Chapter 13: Molecular Markers for the Genetic Improvement of Millets
13.1 Introduction
13.2 Sorghum
13.3 Pearl Millet
13.4 Finger Millet
13.5 Foxtail Millet
13.6 Other Small Millets
13.7 Progress of Molecular Marker Research in Millets
13.8 Future Prospects
References
Chapter 14: Strategies to Build Sustainable Millet Seed Systems
14.1 Introduction
14.2 Factors Leading to Sustainable Seed Security
14.3 Developing a Community-Based Millet Seed System
14.4 The Alternative Integrated Seed-System Model
14.5 Need for a Policy Framework to Build a Viable Local Seed System
14.6 Conclusion
References
Index
End User License Agreement
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Guide
cover
Table of Contents
Preface
Introduction
Begin Reading
List of Illustrations
Chapter 3: Improvement in Finger Millet: Status and Future Prospects
Figure 3.1 Quinquennial area, production and productivity of finger millet in India.
Figure 3.2 Race and sub-races of
Eluesine coracana.
Figure 3.3 Priorities and approaches for genetic improvement in finger millet.
Chapter 4: Foxtail Millet, Setaria italica (L.) P. Beauv.
Plate 4.1 Foxtail millet – field view.
Plate 4.2 Foxtail millet – a single panicle.
Figure 4.1 (a) Organisation of a mature panicle (basal 1/3 region) of foxtail millet. Pb – primary branch; Sb – secondary branch; Tb – tertiary branch; Sc – secondary cluster; Tc – tertiary cluster; S – spikelet; Br – bristle. (b) Spikelet diagram. Gl – lower glume; Gu – upper glume; Le1 – lemma of floret 1; Le2 – lemma of floret 2; Pa1 – palea of floret 1; Pa2 – palea of floret 2; St – stamen; Oy – ovary; Sg – stigma; Sy – style.
Chapter 5: Proso Millet, Panicum miliaceum (L.): Genetic Improvement and Research Needs
Figure 5.1 (a) Proso millet crop; (b) panicles; (c) seed enclosed in glumes and clasping lemma and palea.
Figure 5.2 Probable origin of
Panicum miliaceum
.
Chapter 7: Barnyard Millet: Present Status and Future Thrust Areas
Figure 7.1
Barnyard millet inflorescence and floral parts.
Chapter 10: Insect Pests of Millets and Their Host Plant Relations
Figure 10.1 Sorghum shoot fly damage.
Figure 10.2 Sorghum stemborer damage.
Figure 10.3 Sorghum shoot bug damage.
Figure 10.4 Sorghum aphid damage.
Figure 10.5 Spider mite on sorghum.
Figure 10.6 Cutworm damage in sorghum.
Figure 10.7 Sorghum leaf feeding by red pumpkin beetle.
Figure 10.8 Grasshopper in sorghum.
Figure 10.9 Spodoptera on sorghum earhead.
Figure 10.10 Termite damage in sorghum.
Figure 10.11 Shoot fly damage in pearl millet.
Figure 10.12 Green bug on pearl millet.
Figure 10.13 Green bug on kodo millet.
Figure 10.14 Hairy caterpillar on proso millet.
Figure 10.15 Green bug on barnyard millet.
Figure 10.16 Air-entrainment chamber.
Chapter 12: Nutritional Qualities & Value Addition of Millets
Figure 12.1 Three-year moving average for pearl millet area, production and grain yield; and number of varieties/hybrids released (3-year total) based on ICRISAT-bred material in India.
Chapter 13: Molecular Markers for the Genetic Improvement of Millets
Figure 13.1 Progress of molecular marker research in millets.
Chapter 14: Strategies to Build Sustainable Millet Seed Systems
Figure 14.1 Seed replacement in key foodgrain crops.
Figure 14.2 Seed replacement rate in cash crops.
Figure 14.3 Seed systems tree.
Figure 14.4 Seed supply scenario in formal and informal seed sector in India.
Figure 14.5 Model 1: Individual farmer as seed bank.
Figure 14.6 Model 2: Village based seed banks.
Figure 14.7 Model 3: SHG-mediated system.
Figure 14.8 Model 4: NGO-mediated system.
Figure 14.9 Model 5: KVK-mediated system.
Figure 14.10 Step 1 for the alternative seed system model.
Figure 14.11 Flow diagram showing the organisation of a village seed bank.
Figure 14.12 Fund flow diagram.
List of Tables
Introduction
Table 1 Place of origin and common names of sorghum and millets.
Table 2 Area, yield and production of sorghum and millet by region, 2013.
Table 3 Leading producers of sorghum and millets, 2013.
Table 4 Area (million ha), production (million tonnes) and productivity (kg/ha) of sorghum, pearl millet and small millets in India.
Chapter 1: Sorghum, Sorghum bicolor (L.) Moench
Table 1.1 Sorghum germplasm registered for potential valuable traits.
Table 1.2 Genetics of disease resistance in sorghum.
Chapter 2: Pearl Millet, Pennisetum glaucum (L.) R. Br.
Table 2.1 Promising pearl millet accessions for agronomic and economically important traits.
Table 2.2 Yield of green and dry forage and crude protein contents of sorghum, pearl millet, maize and pigeon pea.
Chapter 3: Improvement in Finger Millet: Status and Future Prospects
Table 3.1 Promising genotypes for economic traits in finger millet.
Chapter 4: Foxtail Millet, Setaria italica (L.) P. Beauv.
Table 4.1 Nutritive value of foxtail millet vs. rice and wheat (per 100 g).
Table 4.2 Status of some of the significant foxtail millet germplasm collections.
Table 4.3 Promising germplasm accessions and other entries of foxtail millet.
Table 4.4 State-wise high-yielding foxtail millet varieties in India.
Table 4.5 Improved foxtail millet varieties released in India with characteristics.
Table 4.6 List of notified foxtail millet varieties in India.
Chapter 5: Proso Millet, Panicum miliaceum (L.): Genetic Improvement and Research Needs
Table 5.1 Nutrient composition of proso millet and cereals.
Table 5.2 Different races of proso millet.
Table 5.3 Proso millet germplasm accessions maintained worldwide.
Table 5.4 Genetic resources identified for various traits in Indian programme.
Table 5.5 Improved varieties released in proso millet in India.
Chapter 6: Genetic Improvement in Little Millet
Table 6.1 State-wise average area, production and productivity in India (2001–2006).
Table 6.2 Proximate composition in comparison with other major cereals.
Table 6.4 List of improved varieties and their characteristics.
Chapter 7: Barnyard Millet: Present Status and Future Thrust Areas
Table 7.1 Nutrient composition of barnyard millet and cereals (per 100 g).
Table 7.2 Wild species of barnyard millet.
Table 7.3 Barnyard millet species, sub-species and races.
Table 7.4 Worldwide barnyard millet germplasm collections.
Table 7.5 Trait-specific barnyard millet germplasm identified in the Indian programme.
Table 7.6 Barnyard millet – released varieties at national level in India.
Chapter 11: Millet Diseases: Current Status and Their Management
Table 11.1 Common diseases of sorghum.
Table 11.2 Common diseases of pearl millet.
Table 11.3 Common diseases of small millets.
Chapter 12: Nutritional Qualities & Value Addition of Millets
Table 12.1 Proximate principles and minerals of Millets and Cereals.
a
Table 12.2 Vitamin content in Millets and Cereals.
a
Table 12.3 Minerals and trace element composition in millets and cereals.
a
Table 12.4 Essential amino acids (mg/G N )in Millets and Cereals.
Table 12.5 Fat and fatty acids content in millets and cereals.
Table 12.6 Oxalic acid and Phytin Phosphorous contents in Millets and Cereals.
Table 12.7 Dietary fibre content in millets and cereals.
a
Chapter 13: Molecular Markers for the Genetic Improvement of Millets
Table 13.1 SSR markers and SNPs developed in sorghum.
Table 13.2 Genetic linkage maps of sorghum constructed during the last 10 years.
Table 13.3 Important major effect genes and QTL mapped in sorghum.
Table 13.4 Important major effect genes and QTL mapped in pearl millet.
Table 13.5 DNA-based markers developed in foxtail millet.
Table 13.6 Important major genes and QTL mapped in foxtail millet.
Table 13.7 Core collections of small millets.
Chapter 14: Strategies to Build Sustainable Millet Seed Systems
Table 14.1 Quality seed requirement and gap in demand in India.
Table 14.2 Comparative chart of different seed systems models.
Millets and Sorghum
Biology and Genetic Improvement
J.V. Patil
This edition first published 2017
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Library of Congress Cataloging-in-Publication Data
Names: Patil, J. V., editor.
Title: Millets and sorghum : biology and genetic improvement / [edited by]Jagannath V. Patil.
Description: Hoboken : John Wiley & Sons, Inc., 2017. | Includesbibliographical references and index.
Identifiers: LCCN 2016049510 (print) | LCCN 2016051303 (ebook) | ISBN9781119123057 (cloth) | ISBN 9781119130789 (pdf) | ISBN 9781119130772(epub)
Subjects: LCSH: Millets. | Sorghum.
Classification: LCC SB191.M5 M555 2017 (print) | LCC SB191.M5 (ebook) | DDC633.1/7-dc23
LC record available at https://lccn.loc.gov/2016049510
A catalogue record for this book is available from the British Library.
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List of Contributors
Kebebew Assefa
Ethiopian Institute of AgriculturalResearch
Debre Zeit Research Centre
Debre Zeit
Ethiopia
Solomon Chanyalew
Ethiopian Institute of AgriculturalResearch
Debre Zeit Research Centre
Debre Zeit
Ethiopia
I.K. Das
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
K.N. Ganapathy
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
Sunil Shriram Gomashe
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
K. Hariprasanna
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
A. Kalaisekar
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
P.G. Padmaja
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
P. Rajendrakumar
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
C.V. Ratnavathi
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
C. Aruna Reddy
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
Ch. Ravinder Reddy
International Crops Research Institutefor Semi Arid Tropics
Patancheru
Hyderabad
India
P. Sanjana Reddy
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
Zerihun Tadele
University of Bern
Institute of Plant Sciences
Bern
Switzerland
Vilas A. Tonapi
ICAR-Indian Institute of MilletsResearch
Hyderabad
India
Preface
Sorghum and millets – pearl millet, finger millet, foxtail millet, kodo millet, proso millet, barnyard millet, little millet, teff millet, etc. – are the main sources of food and fodder for millions of people living in the semi-arid and arid regions of the world. They are the primary sources of dietary fibre, energy, protein, vitamins and minerals for the poor people inhabiting these regions. The growing environments of these crops are characterized by low and erratic rainfall, poor soil fertility, poor agronomic practices, disease and insect pressure and abiotic stress factors such as heat, drought and soil salinity. These crops are grown under marginal conditions unsuitable for various other high-input commercial crops.
The research and development in sorghum and pearl millet is much more advanced as compared to other millets. With the cytoplasmic–nuclear male sterility (CMS) system in place, successful development and spread of hybrids have occurred in both these crops. Small millets in India are a group of six crops such as finger millet, foxtail millet, kodo millet, proso millet, barnyard millet and little millet. After years of neglect, small millets are finding a place in agricultural research agendas in many institutions in India. Doctors and nutritionists are increasingly recommending them as important in health management. Germplasm availability has vastly improved with the launch of the All India Coordinated Small Millets Improvement Project. More than 15,000 accessions of various small millets are now conserved. However, the rate of genetic advancement being made now, barring in finger millet, is slow in all small millets. Demand-driven crop improvement is the current thrust area. Also, millets, being climate-smart crops, have a significant role to play in the current climate change scenario to provide food, feed, fodder and nutritional security to the dryland poor. Teff is a very important millet grown in Ethiopia, accounting for 30% of acreage. Crop improvement has been very slow, and most of the area is under landraces.
It is felt that a review of research in sorghum and millets would help identify the focus areas of research for the reorientation of millets – from a forgotten crop to a smart and nutritious crop. Millets and Sorghum is designed to fulfil this requirement. The book has 14 chapters. The first chapter gives an overview of all the crops. The next nine chapters on individual crops – sorghum, pearl millet, finger millet, foxtail millet, proso millet, little millet, barnyard millet, kodo millet and teff millet – deals with the origins, available genetic resources, genetics, reproduction biology, production constraints, improvement techniques and achievements in each of these crops. Diseases – especially grain mould in sorghum, downy mildew in pearl millet and blast in other millets – play an important role in reducing yield in millets. The research that has been undertaken in enhancing resistance is discussed in a separate chapter on diseases. Except sorghum, insect pests are not a major problem in millets, though incidences of few of them are reported on a small scale. Several pests – such as shoot fly, stem borer, aphids, shoot bug, midge, head bugs, etc. – cause yield losses in sorghum. The chapter on insect pests covers the research that has taken place in deploying insect resistance. Sorghum and millets are renowned for their nutritional benefits. Their nutritional profile and marketing aspects are discussed in a separate chapter. Biotechnology has emerged as a new tool for increasing the precision of plant breeding. Chapter 13 deals with the progress of biotechnology in sorghum and pearl millet, and its initiation in small millets. The success of plant breeding will not make any difference to the average yields of the region unless it is backed by an efficient seed production program. The private seed industry in sorghum and pearl millet is a success story in India mainly due to the availability of hybrid technology. However, there are still several issues to be addressed in these two crops and new strategies to be developed for sustainable seed systems in small millets. These are discussed in Chapter 14 on seed systems.
I am extremely grateful to all the authors and take this opportunity to sincerely thank them for their active cooperation and contribution in this book. I also extend my gratitude to several others who played important roles in the completion of this assignment and for their encouragement – noteworthy among these are T. Mohapatra (DG, ICAR), S. K. Datta (former DDG, Crop Science, ICAR) and J. S. Sandhu (DDG, Crop Science, ICAR). I also gratefully acknowledge the help received from Harshal Gawali in photography, and the secretarial assistance received from N. Kanak Durga, Sanath Kumar and Raghendra Rao. I hope the book will create better awareness of the research and development needs and explore the potential of sorghum and millets for the future. I also hope that Millets and Sorghum will prove to be a valuable reference book for students, teachers and researchers interested in the research and development of these smart crops.
J. V. Patil
Introduction
Millets – The Miracle Grains
C. Aruna Reddy
ICAR-Indian Institute of Millets Research, Hyderabad, India
Sorghum and millets are among the important sources of staple diet in the semi-arid tropic regions of Asia and Africa. Millets comprise of an important group of cereal crops known for their nutritional values. They are gaining importance in a world that is increasingly becoming populous and facing large climatic uncertainties. About 500 million people in more than 30 countries rely on sorghum as staple diet, and more than 90 million people in Africa and Asia depend on millets as staple diet. Sorghum and millets are very hardy and climate-smart crops suitable for environments prone to drought and extreme heat. These crops are adapted to a range of temperatures, moisture-regimes and input conditions supplying food and feed to millions of dryland farmers, particularly in the developing world. These are the major crops successfully cultivated in dry regions where fine cereals such as rice and wheat cannot be grown. The most important characteristic of sorghum and millets is their ability to tolerate and survive under conditions of continuous or intermittent drought periods that result from low or uncertain rainfall. Millets are perhaps the only cereal crop that can grow in arid lands, requiring only 350–400 mm annual rain.
The millet group includes the great millet sorghum (Sorghum bicolor (L.) Moench) and pearl millet (Pennisetum glaucum); and the small millets including finger millet (Eleusine coracana), Italian or foxtail millet (Setaria italica), common or proso millet (Panicum miliaceum), kodo millet (Paspalum scrobiculatum), little millet (Panicum miliare), barnyard millet (Echinochloa frumentacea), fonio (Digitaria exilis) and teff (Eragrostis tef). Of these, fonio and teff are confined to Africa. Other crops are important both in Asia and Africa. Millets are one of the oldest foods known to man and possibly the first cereal grain to be used as food. Millets are also unique due to their short growing season. They can develop from planted seeds to mature, ready to harvest plants in as little as 65 days.
Millets have always been the crops that can be banked upon during situations where there is a risk of famine. They offer a low but more reliable harvest relative to other crops in low-rainfall areas. Small millets are considered as coarse grains and are used as food in situations where other food grains generally cannot be raised, or purchased at economic prices. Therefore, small millets have largely remained as the food of the poor and the less privileged section of the population. The outer tough seed coat and the characteristic flavour of these millets are the main reasons for their reduced popularity among rice- and wheat eaters (Malleshi, 1989). Except finger millet, all the small millet seeds have a slight resemblance with paddy (rough rice) in their morphological features and have an outer husk, bran and starchy endosperm whereas the finger millet seed coat is tightly bound with soft endosperm.
Sorghum and millets have good potential as livestock feed also in the dry zones. With modest water requirements, they have the potential to yield good grain for the farming community and substantial quantities of palatable fodder for cattle. They can make good use of any irrigation water available after the main crops have been harvested, and hence may be fitted in to more productive crop patterns. Almost all the grain produced is used as food in India and in other developing countries, whereas in the United States and other developed countries these are used mainly as feed for calves and birds. Sorghum and millets constitute a major source of energy and protein for millions of people in Asia and Africa. Millets, being nutritionally superior to rice and wheat, provide cheap proteins, minerals and vitamins to the poorest of the poor where the need for such ingredients is the maximum. Practically devoid of any grain storage pests, these small millets have indefinite storage life. The untapped grain yield coupled with nutritional superiority makes small millets the potential future food crop, particularly in the more difficult rainfed areas.
Similar to maize, sorghum and millets also offer opportunities for industrial utilisation. They form an important raw material for potable alcohol and starch production in industrialised countries. The food, fodder, feed and industrial uses of these crops make them important in the agrarian economy of the developing regions of Africa and Asia having low rainfall and limited irrigation resources. Though these cereals have been important staples in the semi-arid tropics for many centuries, there appears to be no reliable historical record of their origin or pattern of dispersion. Since they have been cultivated for so long in so many countries, mainly by smallholder cultivators, they are known by many common and vernacular names (Table 1). In some records, no distinction is made between sorghum and millets; production statistics quoted, even by international authorities, often group the cereals together.
Table 1 Place of origin and common names of sorghum and millets.
Crop
Scientific name
Common names
Place of origin
Chromosome no.
Sorghum
Sorghum bicolor
Great millet, guinea corn, kafir corn, aura, mtama, jowar, cholam, kaoliang, milo, milo-maize
Northeast Africa (Ethiopia–Sudan border)
2n=20 (2x)
Pearl millet
Pennisetum glaucum
Cumbu, spiked millet, bajra, bulrush millet, candle millet, dark millet
West Africa
2n=14 (2x)
Finger millet
Eleusine coracana
African millet, koracan, ragi, wimbi, bulo, telebun
East Africa, India
2n=36 (4x)
Foxtail millet
Setaria italica
Italian millet, German millet, Hungarian millet, Siberian millet
Eastern Asia
2n=18 (2x)
Proso millet
Panicum miliaceum
common millet, hog millet, broomcorn millet, Russian millet, brown corn
Central and eastern Asia
2n=36 (4x)
Barnyard millet
Echinochloa frumentacea
Echinochloa utilis
Indian barnyard millet, sawa millet, Japanese barnyard millet
IndiaJapan
2n=54 (6x)
Kodo millet
Paspalum scrobiculatum
Kodo millet
India
2n=40 (4x)
Little millet
Panicum sumatrense
Little millet
Southeast Asia
2n=36 (4x)
Teff
Eragrostis tef
Teff, lovegrass, annual bunch grass, warm season annual bunch grass
Ethiopia
2n=40 (4x)
Fonio
Digitaria exilis
Fonio, hungry rice, white fonio (En.), fonio blanc, petit mil
West Africa
2n=54
Source: Sorghum and millets in human nutrition, FAO 1995.
Origin and History of Sorghum and Millets
Sorghum, Sorghum bicolor (L.) Moench, which is also known as great millet, belongs to the tribe Andropogonae of the grass family Poaceae. Sorghum is mainly an annual crop, although some have perennial nature in the tropics and can be harvested many times. The greatest variation in the genus Sorghum is observed in the region of the northeast quadrant of Africa comprising Ethiopia, Sudan and East Africa (Doggett, 1988). It appears that sorghum moved into Eastern Africa from Ethiopia around 200 AD or earlier, and was probably taken to India during the first millennium BC. Grain sorghum appears to have arrived in America as ‘guinea corn’ from West Africa with the slave traders about the middle of the nineteenth century.
Pearl millet, Pennisetum glaucum, has many names viz., spiked millet, bajra and bulrush millet (Purseglove, 1972). Pearl millet includes a number of cultivated races. It originated in the tropical Western Africa, where the greatest number of both wild and cultivated forms are found. About 2000 years ago the crop was carried to eastern and central Africa and to India, where due to its excellent tolerance to drought it became established in the drier environments.
Finger millet, Eleusine coracana L., is an important staple food in parts of eastern and central Africa and India. It is an old tropical cereal widely grown in eastern Africa and south Asia. It first occurs in the archaeological records of early African agriculture dating back to around 3000 years, and was introduced to India at least 3000 years ago. It can be stored for long periods without insect damage (Purseglove, 1972) and thus important during famine. In India and Africa, two groups are recognised: African highland types with grains enclosed within the florets; and Afro-Asiatic types with mature grains exposed outside the florets. Uganda is the centre of origin of this crop.
Foxtail millet, Setaria italica L., is also known as Italian millet. Its origin is considered to be in eastern Asia, where it has been cultivated since ancient times. The main cultivation areas are China, Japan and India (Purseglove, 1972). Foxtail millet was also found in the early agricultural sites in Switzerland and Austria dating back to around 3000 years.
Kodo millet, Paspalum scrobiculatum L., is another indigenous cultivated cereal especially of India. The species is widely distributed in damp habitats across the tropics and subtropics of the world. The species could have been domesticated anywhere across its natural range extending from Europe to Japan. It has been grown in China for at least 5000 years (Ho, 1975).
Common millet, Panicum miliaceum L., also known as proso millet, hog millet, broomcorn millet, Russian millet and brown corn, is of ancient cultivation, and is believed to have been domesticated in central and eastern Asia. The progenitor of broomcorn millet is native to Manchuria. The species was introduced into Europe as a cereal at least 3000 years ago. Spikelets and florets of broomcorn millet were found together with remains of foxtail millet in the early farming sites of the European Neolithic.
Little millet, Panicum sumatrense Roth, is grown throughout India to a limited extent up to altitudes of 2100 m. The seeds of little millet are smaller than those of common millet. Barnyard, Japanese barnyard or sawa millet (Echinochloa frumentacea (L.) Link) is the fastest growing of all millets and produces a crop in six weeks. It is mainly grown in India, Japan and China.
Millets – the Climate-Smart Crops
Most of the small millets, particularly little-, proso- and foxtail millets mature early and, therefore, provide one first harvest for human consumption. These are traditionally the indispensable components of the dryland farming system.
The climate change reports from across the globe have raised the threat of climate change to a whole new level, warning of sweeping consequences to life and livelihood, particularly to the world's food supply. Most climate scenarios depict a world warmer by 2 degrees or more by 2100, predicting sharp declines in crop yield for major grains such as wheat and maize. The anticipated climate change makes the drylands a tougher environment to develop and survive in. It has been predicted that there will be a 10% increase in the world's dryland areas with the climate change, with more variability and occurrences of short periods of extreme stresses (drought and heat) during the crop growing seasons. Some estimates suggest that with global warming, 40% of the land now used to grow maize in sub-Saharan Africa will no longer be able to support that crop by the 2030s (The World Bank, 2013). This will have hugely disruptive implications for livelihoods and lives in the semi-arid regions. In the light of changing climate, millets are considered as future crops for farming in the arid and semi-arid tropical regions.
Millets have a wide adaptation. They can withstand a certain degree of soil acidity and alkalinity, stress due to moisture and temperature, and variations in soils from heavy to sandy infertile soils. These crops are grown from sea level to an altitude of 3000 metres and with consequent variation in photoperiod from short to long days. The most attractive feature of sorghum and several of the millets is their capacity to survive and yield grain during continuous or intermittent drought stress. Sorghum can remain dormant during the periods of stress and renew growth when conditions are favourable. Sorghum is more tolerant of flooding than maize but does not grow at its best under prolonged wet conditions. Grain sorghum grows successfully on many soil types but best on medium textured, light textured or sandy soils, and less satisfactorily on clay or heavy textures soils. It tolerates medium to high pH conditions in the soil (Ross and Webster, 1970). Sorghums tolerant to low temperatures and high altitudes are gradually finding a place in Mexico, Brazil and other Latin American countries, in addition to their natural habitat in Ethiopia.
Millet Area and Production Statistics
Detailed area and production data of individual millets are either scanty or currently unavailable. Several kinds of millets are grown in the world, but Food and Agricultural Organization (FAO) data on area, yield and production of all millets are placed together under the general heading of millet. Pearl millet, finger millet and proso millet account for a large proportion of the world production. Sorghum is the world's fifth most important cereal, in terms of both production and area cultivated. All other small millets together are considered the seventh most important cereal grains. All these crops are primarily grown in agro-ecologies subjected to low rainfall and drought. Some cultivars of finger millet are adapted to high altitude conditions in Asia, largely in the foothills of the Himalayas, and in Africa (Purseglove, 1972).
Trends in Area, Production and Productivity of Sorghum and Millets
Sorghum is one of the main staple foods for the world's poorest and most food-insecure people across the semi-arid tropics. Globally sorghum is cultivated on 42 million hectares (ha) to produce 62.3 million tonnes, with productivity hovering around 1.5 tonnes per hectare (FAO stat, 2014). Table 2 provides data on area, yield and production of sorghum in various regions of the world, which shows that Africa followed by Asia and America are the largest producers of sorghum, while 95% of world's millet area lie in Africa and Asia. The region-wise distribution of area for millets is 15.4 million ha in Western Africa and 10 million ha in South Asia. Finger millet is the principal small millet species grown in South Asia followed by kodo millet, foxtail millet, little millet, proso millet and barnyard millet in that order. Foxtail millet and proso millet are important in China. In Africa, finger millet, teff and fonio have local importance. Some small millets are grown in the United States and Europe on a very limited scale.
Table 2 Area, yield and production of sorghum and millet by region, 2013.
Region
Sorghum
Millet
Area (m ha)
Production (m tonnes)
Productivity (kg/ha)
Area (m ha)
Production (m tonnes)
Productivity (kg/ha)
Africa
26.52
25.64
967.08
21.12
15.00
710.23
Eastern Africa
4.75
6.47
1362.8
1.52
1.62
1064.28
Central Africa
1.89
1.99
1056.31
1.15
0.79
686.80
Northern Africa
7.28
5.28
724.9
2.79
1.10
394.80
Southern Africa
0.14
0.19
1319.3
0.25
0.034
134.51
Western Africa
12.46
11.71
940.37
15.41
11.46
743.57
Americas
6.84
23.58
3450.21
0.27
0.43
1622.1
Northern America
2.64
9.88
3739.42
0.26
0.42
1619.52
Central America
1.89
6.64
3520.19
0.0009
0.0008
947.78
South America
2.18
6.95
3191.6
0.0061
0.011
1828.76
Asia
7.88
9.58
1215.09
11.2
13.76
1228.19
Central Asia
0.0009
0.0075
8613.8
0.053
0.061
1137.3
Eastern Asia
0.61
2.94
4801.0
0.79
1.83
2324.0
Southern Asia
6.38
5.40
846.53
10.01
11.57
1155.77
South-eastern Asia
0.26
0.27
105436
0.21
0.19
883.3
Western Asia
0.64
0.96
1516.76
0.14
0.11
788.29
Europe
0.39
1.25
3185.2
0.49
0.63
1282.1
Oceania
0.60
2.23
3748.8
0.035
0.04
1142.86
World
42.2
62.30
1475.24
33.1
29.86
901.73
Source: FAO database 2014.
The five largest producers of sorghum in the world (Table 3) are the United States (16%), Nigeria (11%), Mexico (10%), India (8.5%) and Ethiopia (7%). Together these five countries account for 52.5% of the total world production. India (36.5%) is the largest producer of millets, followed by Nigeria (16.7%), Niger (10%), China (5.9%) and Mali (4.4%). All these countries together contribute to 73.5% of world millet production.
Table 3 Leading producers of sorghum and millets, 2013.
Sorghum
Millets
Country
Area (m ha)
Production (m tonnes)
Productivity (kg/ha)
Country
Area (m ha)
Production (m tonnes)
Productivity (kg/ha)
USA
2.64
9.88
3739.4
India
9.2
10.91
1185.9
Nigeria
5.50
6.70
1218.2
Nigeria
4.0
5.00
1250.0
Mexico
1.69
6.31
3735.0
Niger
7.10
2.99
421.83
India
6.18
5.28
854.37
China
0.72
1.75
2439.3
Ethiopia
1.85
4.34
2348.5
Mali
1.44
1.15
801.9
Argentina
0.89
3.64
4085.2
Burkina Faso
1.33
1.08
812.7
China
0.59
2.89
4954.2
Cameron
0.07
0.97
1385.7
Australia
0.60
2.23
3747.4
Ethiopia
0.43
0.81
1869.8
Burkina Faso
1.81
1.88
1040.9
Senegal
0.71
0.57
801.1
Niger
3.1
1.29
415.16
USA
0.26
0.42
1619.5
Total
24.85
44.44
25.26
25.58
World
42.2
62.3
1475.24
World
33.1
29.86
901.73
Because of the higher yield per unit area, North and Central America produce the highest quantity of sorghum (16% of total production). In Asia, sorghum is extensively cultivated in India, China, Yemen, Pakistan and Thailand. Production in Europe is limited to a few areas in France, Italy, Spain and the southeastern countries. In Oceania, Australia is the only producer of significance.
World sorghum production expanded from 40 million tonnes at the beginning of the 1960s to 62 million tonnes during 2012–2013, even though there was a decline in sorghum growing area from 46 million ha in 1961 to 42 million ha in 2013. Millet production increased from 25 million tonnes in 1961 to 30 million tonnes in 2013, and the area was decreased from 43 million ha in 1961 to 33 million ha in 2013.
Sorghum is grown in two contrasting situations in different parts of the world based on production and utilisation patterns. In the developed world there is intensive, commercialised production, mainly for livestock feed. Hybrid seed, fertiliser and improved water management technologies are used fairly widely, and yields average 3–5 t/ha. In most of the developing world, there is sharp contrast with the low-input, extensive production systems, where sorghum is grown mainly for food. While improved varieties are being adopted in such systems, particularly in Asia, management practices generally remain less intensive than in the commercialised systems. Fertiliser application rates are low and the adoption of improved moisture conservation technologies is limited. As a result, average yields remained low between 0.5 and 1.0 t/ha in many areas but gradually increasing in spite of area decline in some regions.
Millet production systems in Africa and Asia are generally characterised by extensive production practices and limited adoption of improved varieties. Yield average is still only 0.3–1.0 t/ha. While hybrids are being adopted in parts of Asia, most of the world's millet area remains under traditional varieties. Few farmers apply fertilisers or use improved moisture conservation practices. Therefore, the yield levels remain low for long but increase wherever improved hybrids and management practices are increasingly adopted as in India.
Trends in Area, Production and Productivity of Sorghum and Millets in India
Sorghum
India contributes to about 16% of the world's sorghum production. It is the fourth most important cereal crop in the country. In India, this crop was one of the major cereal staples during the 1950s and occupied an area of more than 18 million ha but has come down to 6.61 million ha in 2013. The decline has serious concern on the cropping systems and the food security of these dry land regions of the country. The increased productivity of sorghum has not been able to compensate the loss in area turning the production to be negative.
Pearl Millet
Pearl millet is a major warm-season cereal grown largely in the arid and semi-arid tropical regions of Africa and Asia with India accounting for the largest area (7.2 million ha). The diversification of cultivar base with mostly dual-purpose hybrids has led to 24 kg/ha/year of grain yield increase during the last few decades as compared to only 5.2 kg/ha/year of yield increase during the pre-hybrid phase of 1950–1965. Development of improved crop cultivars is just one major component of technological interventions to enhance food and nutritional security. Improved crop management technologies with potential to substantially increase pearl millet grain yield have been developed.
Small Millets
The crop-wise data on area, production and yield for individual small millets are not available, except for finger millet. Therefore, the statistical data are given separately for finger millet; other small millets are grouped together. The area where small millets are cultivated in India during the last 6 decades has significantly reduced from 8 million ha during 1949–1950 to around 2.3 million ha during 2012–2013. This is also reflected in the diminishing production, from around 4 million tonnes produced in late 1940s to around 2.5 million tonnes during 2011–2012. The loss of area is very severe in all small millets other than finger millet. However, in the last 15 years, the finger millet also has lost ground and its area has come down from 2.4 million to 1.2 million ha.
Despite the reduction in area, the total production is not much affected. By and large, the low productivity of these crops is largely due to the meagre attention received in terms of inputs; which is further compounded by low-value status of grains. The bulk of small millet production in India is of finger millet (80%) and the remaining from kodo millet, little millet, foxtail millet, barnyard millet and proso millet in that order.
In general, the area and production of small millets are coming down. The reasons are many: the low productivity, poor resources base, lack of input, price and procurement support coupled with no alternate food uses, campaigns for value-added oilseeds and pulses and ‘urbanisation’ of food habits are slowly displacing the small millets to more and more marginal, fertiliser-hungry and water-starved abandoned soils.
Finger Millet
The area cultivating finger millet has fluctuated from 2.30 to 1.1 million ha in different years during 1955–2013 and the production has fluctuated from 1.85 to 1.59 million tonnes. The increase in production is mainly due to the raise in productivity from 800 kg/ha during 1955–1956 to 1428 kg/ha during 2012–2013 (Table 4).
Table 4 Area (million ha), production (million tonnes) and productivity (kg/ha) of sorghum, pearl millet and small millets in India.
Crop/ Year
Category
1955–1956
1965–1966
1975–1976
1985–1986
1995–1996
2005–2006
2012–2013
Sorghum
Area
17.36
17.68
16.09
16.10
11.33
8.68
6.18
Production
6.73
7.58
9.50
10.20
9.33
7.63
5.33
Productivity
387
429
591
633
823
880
863
Pearl millet
Area
11.34
11.97
11.57
10.65
9.32
9.58
7.20
Production
3.43
3.75
5.74
3.66
5.38
7.68
8.74
Productivity
302
314
496
344
577
802
1214
Finger millet
Area
2.30
2.70
2.63
2.41
1.77
1.53
1.11
Production
1.85
1.33
2.80
2.52
2.50
2.35
1.59
Productivity
800
492
1064
1049
1410
1534
1428
Small millets
Area
5.34
4.56
4.67
3.16
1.66
1.06
0.75
Production
2.07
1.56
1.92
1.22
0.78
0.47
0.43
Productivity
388
341
412
386
469
443
571
Source: Agricultural Census, Directorate of Economics and Statistics, Department of Agriculture & Cooperation, Government of India.
Millets are the main component for food and fodder security in the semi-arid tropics. They do have socio-economic, food/feed, health and environmental impacts on the poor farmers of these regions. Substantial advances made in the improvement of millets have brought in the economic transformation of millions of rural families in these regions. In the light of climate change, millets are extremely vital for tackling the food crisis and providing food security. Any improvement in production, availability, storage, utilisation and consumption of these food crops will significantly contribute to the household food security and nutrition of the inhabitants of these areas.
Millets – Store Houses of Nutrition
The major health concern in most of the developing countries is hidden hunger or micronutrient deficiency. This is more prominent in the arid and semi-arid regions, where people are too poor to be able to afford more nutritious foods. Even while vast segments of resource-poor people suffer from malnutrition, there is a growing incidence of obesity and chronic diseases such as diabetes, cardiovascular diseases, cancer, etc. The reason for these dual types of situations could be due to changing food habits, the absence of millets from diet being one of them. Their presence in the world food basket had been declining over the years. However, there is an increasing recognition of their favourable nutrient composition and utility as health food, in the context of increasing lifestyle diseases. Sorghum and millets offer unique advantage for health being rich in micronutrients particularly minerals and B vitamins. The neutraceutical value of these grains, by virtue of their high dietary fibre and low glycemic index, is receiving increased attention. Their good nutritional value including high levels of quality protein, ash, calcium, iron and zinc, makes millet nutritionally superior to most cereals. Additionally millets are also rich in health promoting phytochemicals and have received attention for their potential role as functional foods.
Being non-glutinous, millets are safe for people suffering from gluten allergy and celiac disease. They are non-acid forming, and hence easy to digest. Epidemiologically lower incidence of diabetes is reported in millet consuming populations (Saleh et al., 2013). The diabetes preventing effect of millets is primarily attributed to the high fibre content. Some antioxidant phenols in millets also tend to have antidiabetic effects. Sorghum is rich in phenolic compounds and antioxidants (Awika et al., 2004). Among minor millets, foxtail- and barnyard millets have low glycaemic index (40–50) which helps to manage blood glucose levels and prevent diabetes.
Millets being high in fibre, antioxidants and complex carbohydrates are potential candidates for having beneficial effects against diseases such as cardiovascular diseases, cancer, etc. in general. Finger millet is rich in niacin, which helps reduce high cholesterol level. It is very high in calcium (340 mg/100 g, i.e. three times more than milk) (Kannan, 2010) making it important for lactating women and children. Pearl millet and sorghum are rich sources of energy (about 350–360 k cal/100 g), with comparable levels as wheat and rice (Nambiar et al., 2011). Teff contains high level of iron. Finger millet protein is unique among cereals to possess very high levels of sulphur amino acids.
Genetic Resources and Crop Improvement of Millets
As the small millets are indispensable to agriculture in semi-arid tropics, there is increasing realisation of the need to improve the productivity of these crops through modern methods of breeding. The ultimate goal of breeding sorghum and millets remains improvement of grain yield including maximisation of biomass and the harvest index. The major objectives for millet improvement for grain and forage include improved adaptation, increased drought tolerance, ability to put forth quick growth and increased resistance to economically important diseases and pests. Quality aspects of both grain and fodder are also important. Improvement in resistance for important biotic and abiotic stresses forms another important objective in millet improvement. Among the abiotic stresses, drought plays an important role since all the millets are grown rainfed. The major biotic stress being grain moulds, shoot fly and charcoal rot in sorghum, downy mildew in pearl millet and blast in finger millet.
The pollination behaviour of different millet crops range from complete self-pollination to predominant cross-pollination. Majority of the small millets are predominantly self-pollinated crops. The degree of selfing varies from near cleistogamy in kodo millet to marginal outcrossing in other small millets. Sorghum is also a predominantly self-pollinated crop with the cross-pollination varying from 2 to 20% (which puts it under often cross-pollinated crop category) in different places and different varieties, more in loose panicles than in compact ones, and hence has the advantage of possessing complete self-pollination to total outcrossing due to its floral biology, genetic and cytoplasmic genetic male sterility and self incompatibility. Breeding methods relevant to self- as well as cross-pollinated crops are, therefore, applied to breed pure line varieties, hybrids and populations. Pearl millet is predominantly protogynous and hence highly cross-pollinated. The large amount of cross-pollination in pearl millet results in the plants being highly heterozygous. In this respect a field of pearl millet shows considerable genetic variability within a single open pollinated variety. Hence the breeding methods that are followed for cross-pollinated crops are followed for pearl millet improvement, and the main breeding approaches are those that aim towards development of hybrids, composites and synthetics.
The ceiling to yield in sorghum and pearl millet has been raised substantially through the commercial use of hybrids during the last 5–6 decades. In both the crops, gene-cytoplasmic sterility-restorer systems have added a new dimension to yield improvement. Considerable progress has also been made in incorporating resistance to major diseases and pests. In case of small millets, systematic improvement has not been attempted until recently.
Small millets are highly self-fertilised crops and pure line selection has been primarily used to improve the performance of land races. Hybridisation, however, offers immense potential for combining the desirable features. Contact, hot water and gametocide methods have been used in hybridisation with certain amount of success in these crops. The smallness of the spikelets and their delicate nature have been hindering hand emasculation. There is an urgent need to standardise hybridisation techniques for changing the genetic background of the local cultivars. The discovery of male sterility in foxtail millet in China augurs well for the improvement of this crop. Similar mechanisms and also mechanisms like protogyny which promote cross-pollination need to be looked for in other small millets.
Sorghum and millets possess a wealth of genetic diversity. India has assembled more than 15 000 collections of small millets at Bangalore, the headquarters of the Small Millets Improvement Project. Similarly China maintains a rich source of foxtail millet germplasm; earlier Soviet Union had excellent proso millet collections. Africa has assembled teff in Ethiopia and finger millet in Kenya and Uganda. However, there are many areas in India as well as in other countries still unexplored and there is an urgent need to retrieve the genetic diversity under natural conditions.
Promising germplasm for different traits have been identified in sorghum and millets and those have been used in the millet improvement programmes across the countries. Sorghum has five basic races, viz., bicolor, durra, guinea, caudatum and kafir and their ten derived hybrid races. Useful genes for different traits from these germplasm have been exploited in the sorghum improvement programmes across the globe. The male sterile kafir introduced from America is being utilised for exploitation of heterosis in sorghum. Cultivated pearl millet has four basic races, viz., typhoides, nigritarum, globosum, leonis. The zera zera sorghum from the Sudan–Ethiopian border and the iniadi germplasm of pearl millet from the Togo–Ghana–Burkina Faso–Benin region of western Africa have been most extensively used in sorghum and pearl millet breeding programmes worldwide (Rai et al., 1999).
In the case of small millets, the utilisation has been drastically restricted by the difficulties in artificial hybridisation. Except for finger millet and to some extent foxtail millet, hybridisation and recombination breeding in small millets have not been attempted in India. Improvement in these crops so far has been through single plant selection, evaluation and release of promising germplasm. The Indo-African crosses have provided the real backbone for breaking the grain-yield barriers in the improvement of finger millet. They helped in increasing finger millet productivity by more than 50% (Seetharam, 1982). The finger millet germplasm, especially from Africa, possess genes for blast resistance, robust growth, early vigour, large panicle size, finger number and branching and higher grain density. Similarly accessions possessing high protein and desirable physiological attributes, with high carbon dioxide fixation and low leaf area suitable for rainfed conditions have been identified (Seetharam et al., 1984; Sashidhar et al., 1986).
In kodo millet, raceme morphology allows for the recognition of three cultivated complexes. The most common kodo millets are characterised by racemes with the spikelets arranged in two rows on one side of a flattened rachis, as is also typical of wild P. scrobiculatum. Two variations on this spikelet pattern often occur in the same field as the more common phenotype. Hybridisation between cultivated varieties and between weedy and cultivated races is common. This explains the absence of clear racial differentiation, even after some 3000 years of cultivation. Kodo millet is cleistogamous, but protogynous types have been selected, and crosses made. In the Indian wild types the stigmas protrude from the spikelets. The observation by de Wet et al. (1983), on the lack of racial differentiation after 3000 years, suggests that it could be a very interesting crop to work with.
Foxtail millet is commonly classified into a European complex (race moharia) and a Far Eastern complex (race maxima). Race moharia includes cultivars with relatively small and erect inflorescences, while race maxima is characterised by large and pendulous inflorescences. Two inflorescence types of race maxima are recognised by Gritzenko (1960). Plants with small, essentially erect, and compact inflorescences occur in northwestern China and Mongolia. Plants from eastern China, Japan and Korea typically have large, compact and pendulous inflorescences. Cultivars from India are morphologically distinct from those of Europe and the Far East, and are recognised as race indica by Prasada Rao et al. (1987). The variability available in foxtail millet for panicle shape, size, arrangement of spikelets, tillering, seed size and colour are very diverse offering great scope for exploitation (Harinarayana and Seetharam, 1981).
Cultivated kinds of P. miliaceum are commonly subdivided into five subspecies (Lyssov, 1975). These are here recognised as races without taxonomic validity. Race miliaceum resembles wild P. miliaceum in inflorescence morphology. It is characterised by large, open inflorescences with suberect branches that are sparingly subdivided. Race patentissimum with its slender and diffused panicle branches is often difficult to distinguish from race miliaceum. These two races occur across the range of broomcorn millet cultivation from Eastern Europe to Japan. Highly evolved cultivars of broomcorn millet have more or less compact inflorescences. These are classified into races contractum, compactum and ovatum. Cultivars included in race contractum have compact, drooping inflorescences. Those belonging to race compactum have cylindrical shaped inflorescences that are essentially erect. Cultivars with compact and slightly curved inflorescences that are ovate in shape are included in race ovatum.
A different Panicum species (sama) is grown as a cereal in the Eastern Ghats of India (Rangaswami Ayyangar and Achyutha Wariar, 1941). This species, P. sumatrense Roth. ex Roem. and Schult., represents the domesticated complex of the weedy P. psilopodium Trin. (de Wet et al., 1984). The commonly cultivated kind differs from wild P. psilopodium with which it crosses to produce fertile hybrids, primarily in having lost the ability of natural seed dispersal. This race of sama is highly tolerant to heat and drought stress. In the more favourable agricultural habitats of the Eastern Ghats a robust race of sama is grown. The inflorescences of this race are strongly branched and compact.
