1. Examination of Brassicaceae seed meal as a soil amendment to control Pythium ultimum 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
Type
B. napus
B. juncea
S. alba
Allyl -
300.9
3-But
34.4
1.3
4-Pent
8.4
0.1
2-Hyd-3-But
75.4
8.5
OH-Benz
235.6
Total
114.2
302.9
244.1

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 Each experimental unit
Pythium ultimum.
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 Days after planting Tomato seedling emergence

16. Results
Seedling emergence (%)
Seed meal type

17. Results Seedling emergence (%) Days after planting
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