Classifying the genetic diversity of sorghum: a revised classification of sorghum J. A. Dahlberg, Kearney Agricultural Research and Extension Center – University of California, USA; and D. T. Rosenow, formerly Agricultural Research and Extension Center – Texas A&M University, USA

1 Introduction

2 The major races of sorghum: Bicolor, Guinea, Caudatum, Kafir and Durra

3 Working groups: Bicolor (1)

4 Working groups: Guinea (2)

5 Working groups: Caudatum (3)

6 Working groups: Kafir (4); Durra (5)

7 Working groups: Guinea-bicolor/Bicolor-guinea (6); Caudatum-bicolor/Bicolorcaudatum (7)

8 Working groups: Kafir-bicolor/Bicolor-kafir (8); Durra-bicolor/Bicolor-durra (9)

9 Working groups: Guinea-caudatum/Caudatum-guinea (10); Guinea-kafir/Kafirguinea (11)

10 Working groups: Guinea-durra/Durra-guinea (12); Kafir-caudatum/Caudatumkafir (13)

11 Working groups: Durra-caudatum/Caudatum-durra (14)

12 Working groups: Kafir-durra/Durra-kafir (15); Annual wild (16)

13 Working groups: Sorghum bicolor subsp. verticilliflorum (17); Perennial wild (18)

14 Working groups: Unclassified (19); Breeding material (20); Mixed (21)

15 Acknowledgements

16 Appendix: Sorghum Conversion Program

17 References

Drs Jeff Dahlberg and Darrell Rosenow have worked to modify the classification schemes of sorghum as proposed by Harlan and DeWet, Doggett, and Murty and Govil. Dahlberg (2000) proposed an Integrated Classification of Sorghum for use by plant breeders throughout the world so that sorghum classification could be more unified in its application in both research and plant breeding. This scheme does not require extensive knowledge of variability found within sorghum, but relies on the classifier’s ability to distinguish between the major and intermediate races as a way to move into a more precise classification based on the working groups. Following are excerpts from Dahlberg’s 2000 chapter that attempts to clarify the reasoning for the new system.