A presentation prepared by Yaima Arocha and John Lucas for the ASARECA/ILRI Workshop on Mitigating the Impact of Napier Grass Smut and Stunt Diseases, Addis Ababa, June 2-3, 2010.

1. Napier grass stunt and head smut diagnostics Yaima Arocha and John Lucas Presented at the ASARECA/ILRI Workshop on Mitigating the Impact of Napier Grass Smut and Stunt Diseases, Addis Ababa, June 2-3, 2010

3. NAPIER GRASS STUNT

8. Napier Head Smut Disease Napier smut (NHS) due to infection by Ustilago kamerunensis .

13. Ustilago cynodontis From smutted Cynodon , Ethiopia, 2007 Putative U. kamerunensis From Kenya, 2007 Cultural morphology 1

14. Mixture of budding and filamentous cells characteristic of smut fungus Cultural morphology 2 . Microscopic characters

15. Molecular Identification of Ustilago kamerunensis PCR amplifications from U. kamerunensis (2-4, 6-8, 10-12) and U. cynodontis (5, 9, 13) with primers targeting the  -tubulin gene (F1/R2, 2-5; and F2/R1, 10-13) and ITS region (ITS1/4, 6-9). Lanes 14-16. Positive controls group 16SrIII and 16SrXI (16). More data can be obtained from authors 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

16. Hybridization signals from PCR products from Kenyan (UK) isolates with the  -tubulin probe.

17. NHS-infected Napier source plants (Kenya)

18. Uniformly smutted inflorescences of field-infected Napier plants

19. Distorted inflorescence

20. NG-1 month- post-inoculated plants

22. PCR amplicons from inoculated plants using  -tubulin primers U U cynodontis reference U. kamerunensis Plant Control samples

24. Draft diagnostic lab manual Edition 3