This document summarizes research on stored product protection in Germany with a focus on tropical agriculture and cooperation. It discusses common stored product pests like insects, mites, rodents, and microorganisms. Significant food losses of up to 1/3 globally are reported. Integrated approaches to stored product protection including prevention, early detection, and control methods like physical, chemical and biological controls are outlined. Specific research is described on using phytochemicals and diatomaceous earths for control of stored product pests. The importance of cooperation to further knowledge in this area is emphasized.

1. 1 cornel.adler@jki.bund.de
Agri 4D, SLU, 25 Sept. 2013
Stored product protection research in
Germany with focus on tropical agriculture
and cooperation
• Introduction
• Insect-proof storage
• Phytochemicals
• Diatomaceous earths
• Conclusions
Cornel Adler
Julius Kühn-Institut
Berlin
www.jki.bund.de

2. 2 cornel.adler@jki.bund.de
What are stored product pests?
Insects
Beetles (approx. 60 species)
Moth (approx. 20 species)
Dustlice (approx. 10 species)
Mites (approx. 10 species)
Rodents
Mice
Rats
Birds
Microorganisms, microbial deterioration (mycotoxins!)
Hygiene pests
Cockroaches
Flies
Ants

3. 3 cornel.adler@jki.bund.de
FAO-Study „Save Food!“ 5/2011
Losses in food world-wide: 1/3

4. 4 cornel.adler@jki.bund.de
Losses & Costs
But infested grain is also damaged, moist, warm
(additional losses due to pest cotrol measures, quality
loss, risk for further pest attack (e.g. mites or fungi)
Germany
Grain harvest 2009: almost 50 mio. t
If losses estimated to 4 % (FAO) by weight
4 % = 2.000.000 t at 250,- Euro/t
= 500 mio. Euro

5. 5 cornel.adler@jki.bund.de
Integrated Stored Product Protection
Pest
prevention
Early pest
detection
Pest
control
physical
chemical
biological
Biotechnical
e.g. DE
Structural
design
Cooling
Drying
Sanitation
Packaging
Visual
inspection
Check:
temperature
moisture
movement
product
density
bioacoustics
traps
Inspection
sampling

6. 6 cornel.adler@jki.bund.de
Phytochemicals: Attractants
What do insects smell?
Identify attractive volatiles
Oils for traps better than food baits (no development)
• Which combination?
• Which pure compounds?
• Fruity volatiles most attractive to
Plodia interpuntctella (Adler et al. 2000)
Preliminary test with food-
grade aromas:

7. 7
Response of P. interpunctella to apricot volatiles
Results
[1] 3-Methyl-1-butanol acetate
[2 ] 1-Butanol
[3 ] 3-Methyl-1-butanol
[4 ] 1-Pentanol
[5 ] 3-Hydroxy-2-butanone
[6 ] 1-Hexanol
[7 ] 2,6,11-Trimethyl pyrazine
[8 ] Acetic acid
[9] Ethyl benzoate
[10] Benzyl alcohol
(Ndomo et al. 2012)
Now:
• dose-response-test
• behavioural test (eg.
flight chamber)

8. 8 cornel.adler@jki.bund.de
Neem to protect maize
Influence of sun drying and shelling
In Northern Cameroon on contents
of Azadirachtin and efficacy
(PhD K. Tofel)

9. 9 cornel.adler@jki.bund.de
Diatomaceous earths (DE)
dried, milled, sifted

10. 10 cornel.adler@jki.bund.de
Diatomaceous earths (DE)
Registered: 10g/m2
(structures)
1-2kg/t (grain)
Foto: Biofa (Brazil)

11. 11 cornel.adler@jki.bund.de
Comparison of DEs (SEE ERA NET Project 2008)
SilicoSec, GR Begora, Lower SR. GR Kriti, Vranje3/12/07
Slob., GR Elas., SR Vranje, SRKol.518,Kol.517, Kol.516, GER-SR, Control
Efficacy much higher at 30°C than at 20°C
Now tests in Cameroon (Ngaoundere Univ., E. Nukenine)
Athanassiou et al. (2011)

12. 12 cornel.adler@jki.bund.de
Conclusions
• Prevention is better than control
- store dry, cool, hermetically, as short as possible
• Monitoring for early detection
- traps with food or pheromone lures, thermometers, acoustics, etc.
• Stored product pests are competitors to man
- infestation is indicator for inefficient protection
• Pest control with most suitable method
- low-risk methods gain importance, solutions require knowledge,
the best way to aquire knowledge is cooperation!

13. 13 cornel.adler@jki.bund.de
Identified plants plant parts used protected stored products
Clausena anisata (Rutaceae) leafy branches maize, beans
Cypressus sempervivens (Cypr.) leafy branches maize, beans, cowpea
Capsicum frutescens (Solanac.) fruits beans, cowpea
Chenopodium ambros. (Chenop.) leaves maize, beans, potato
Eucalyptus spp. (Myrtaceae) leaves maize, beans, cowpea
Lantana camara (Verbenaceae) leaves beans, potato
Plant parts as
traditional insecticides
Survey in Western Highlands of Cameroon (Tapondjou et al. 2000)

14. 14 cornel.adler@jki.bund.de
Temperature (°C) and insect development
Lethal > 50 Death in minutes
>45 Death in hours
Suboptimum >35 Development stops
Optimum 25-33 Max. development
Suboptimum < 25 Slow development
< 13 Development stops
Letal < 6 Movement stops,
unadapted indiv. die
< -5 Adapted indiv. die
< -15 Death in minutes
Fields (1992)

15. 15 cornel.adler@jki.bund.de
Etheric oils in Clausena anisata,
identified by retention time (RT)
(60 m DB wax fused silica caplillar column)
Component
RT
GC- surface
(%)
leaves seeds
Alpha Pinene 5,9 - 0,4
Sabinene 7,5 0,5 3,1
Myrcene 8,2 0,7 28,9
Limonene 9,1 - 0,4
Cis Ocimene 9,7 - 0,7
Gamma –Terpinene 10,2 1,8 4,9
p-Cymene (Cymol) 10,8 - 6,3
4-Terpineole 19,5 - 0,4
Germacrene D 22,2 1,0 -
Trans Anethole 24,9 80,8 32,9
p-Anisaldehyde 29,5 - 15,4
Trans Isoeugenol Methylether 32,4 11,5 2,6

16. 16 cornel.adler@jki.bund.de
Efficacy of pure compounds
Dosage: 0-60µl/ml or 0-400 mg/ml Acetone
0,5 ml on filterpaper, 20 T. confusum adults added
compound LD50 LD95 Mortality (%)
4-Allyl-anisole (µl/cm2
)
24 h 0.05 0.11 43.35±9.40
48 h 0.05 0.10 49.65±9.12
Linaloole(µl/cm2
)
24 h 0.21 NA 15.75±2.50
48 h 0.19 NA 15.75±2.50
Terpineole (µl/cm2
)
24 h 0.29 NA 22.95±6.57
48 h 0.14 0.42 26.85±7.42
Thymole (mg/cm2
)
24 h 1.46 1.98 27.20±8.27
48 h 1.32 1.44 32.05±9.09
Zimtaldehyde(µl/cm2
)
24 h 0.04 0.05 80.35±7.15
48 h 0.04 0.04 81.10±7.12
Values are means of 3 replicates. NA = Not applicable
Ojjimelukwe et al. 2001

17. 17 cornel.adler@jki.bund.de
Reasons for greatest losses
• weather extremes (warm, humid)
• loss of social structures and structural design (poverty)
• political instability/ war
• lack of motivation of storage manager
(no incentive, low value)
• new storage goods, new pests, new storage method
• regionally scattered
• mykotoxins cause health hazards

18. 18 cornel.adler@jki.bund.de
Heat for structural treatments
www.thermonox.de www.biotech.at

19. 19 cornel.adler@jki.bund.de
Results - heat
0
10
20
30
40
50
60
70
0 600 1200 1800 2400 3000 3600 4200 4800
Time (min)
Temperature(°C)
Old mill
cellar
room above lift
dead
alive
Tropics:
Solar heat + vent for fast treatment at 60°C?

20. 20 cornel.adler@jki.bund.de
In brackets the most tolerant stage,
E = eggs; L = larvae; P = pupae; A = adults
Lab data on the efficacy of heat
Exposure times needed for complete control:
Tierart 45°C 50°C 55°C
E. kuehniella 660 min (11h) (E) 27 min (P) 7 min (P)
S. granarius 540 min (9h) (L) 40 min (L) 30 min (L)
S.zeamais 660 min (11h) (L) 45 min (A) 30 min (A)
C. pusillus 1200 min (20h) (L) 65 min (L) 20 min (L)
T. castaneum 1800 min (30h) (L) 35 min (L) 20 min (L)
L. serricorne 2400 min (40h) (L) 370 min (E) 45 min (E)
R. dominica 6000 min (100h) (L) 370 min (L) 45 min (L)
Adler (2006, 2007, 2008)