Ensuring the genetic diversity of sorghum Hari D. Upadhyaya and Mani Vetriventhan, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), India

1 Introduction

2 Origin, domestication and taxonomy of sorghum

3 Sorghum germplasm conservation and diversity

4 Factors shaping sorghum diversity

5 Geographical distribution of sorghum germplasm

6 Germplasm gap analysis of sorghum

7 Ensuring diversity in sorghum

8 Future trends and conclusion

9 Where to look for further information

10 References

Sorghum [Sorghum bicolor (L.) Moench] is the fifth major cereal crop in the world in terms of area under cultivation and level of production, and is a staple food crop for millions of the poorest and most food-insecure people in the semi-arid tropics. Africa (39.8%), the Americas (38.5%) and Asia (16.9%) are the main sorghum-producing regions in the world, and together contribute about 95% of the world’s total sorghum production. The major sorghum-producing countries are the United States, Mexico, Nigeria, India and Sudan (averaged over 2010-14). Sorghum production in Asia decreased from 15.5 million tons in 1961 (maximum production being reached during the 1970s and 1980s) to 9.6 million tons in 2014, although this reduction was compensated by increases in the area under cultivation (from 13.2 million hectares in 1961 to 29.0 million hectares in 2014) and in the levels of production (from 10.7 million tons in 1961 to 29.0 million tons in 2014) in Africa (https://www.faostat.fao.org; data accessed in July 2016). The world’s sorghum production increased from 40.9 million tons in 1961 to 67.9 million tons in 2014, with maximum production being achieved during the 1980s. The world’s sorghum productivity has been increased from 889 kg ha−1 in 1961 to 1535 kg ha−1 in 2014, which is still low. Adoption of improved sorghum cultivars and management practices contributed to the productivity gains though large differences exist in different parts of the world.