MAXWELL HANDISENI Plant, Soil and Entomological Sciences Idaho OilSeed Conference 2009

1. Examination of Brassicaceae seed meal as a soil amendment to control Pythiumultimum in tomato (Lycopersicum esculentum) and pepper (Capsicum annuum) production systems. MAXWELL HANDISENI Plant, Soil and Entomological Sciences Idaho OilSeed Conference 2009

2. Outline • Introduction • Materials and Methods • Results • Conclusion

3. Introduction • Tomato and peppers among most valuable vegetables. • Traditional soil borne disease management relied heavily on chemicals. • Brassicaceae material associated with soil borne disease suppression. • Glucosinolate products responsible. • Variability of glucosinolate type and content.

6. Glucosinolate Breakdown + Glucose + HSO-4 S-C6H11O5 R – C NOSO-3 S - R – C N - H2O Myrosinases R-N=C=S Isothiocyanate R-CN Nitrile & Sulfur R-S-CN Thiocyanate

7. Glucosinolate Profiles

8. Materials and Methods

9. Materials and Methods Three meals examined: • Sinapis alba (‘IdaGold’), yellow mustard. • Brassica juncea (‘Pacific Gold’), Oriental mustard. • Brassica napus (‘Dwarf Essex’), rapeseed.

10. Materials and Methods Meal treatments: • 0.5% (w/w) denatured seed meal. • 0.5% (w/w) non denatured seed meal. • 0.5% (w/w) as a non glucosinolate seed meal. • Pythium and no amendment control • No Pythium and no amendment control .

11. Materials and Methods Pathogen species • Pythium ultimum. Pathogen species • Tomato (“Red Scarlet”) • Pepper (“New Ace”) Each experimental unit • 7 conical pots each with two seeds of the same crop.

12. Materials and Methods Design • Randomized Complete Block Design • Three replications and repeated 2 times. Data collected • Seedling emergence daily from 7 to 11 DAP. • Final seedling emergence.

13. Results

14. Results Seedling emergence (%) Seed meal type

15. Results Tomato seedling emergence Seedling emergence (%) Days after planting

16. Results Seedling emergence (%) Seed meal type

17. Results Pepper seedling emergence Seedling emergence (%) Days after planting

18. Conclusions • B. juncea, B.napus seed meals increased pepper and tomato seedling emergence. • Both S. alba seed meals reduced tomato and seedling emergence. • Mechanism for pathogen suppression are dependent but not limited to glucosinolate products content. • Performance of seed meals vary from species to species.

19. Acknowledgements • Dr Jack Brown-Major Professor • Dr Robert Zemetra • Dr Mark Mazzola • Canola Lab Crew: • Jim Davis • Clark Neely • Donna Brown • Mary Lauver • Lindy Seip

20. QUESTIONS