Hermetic Storage as a
Solution for Prolonged
Storage of Seed
Presentation to Purdue Hermetic Storage Conference
April 10-12, 2012 Accra, Ghana
Rule of Harrington (1972)
“ Life of seed is halved:
 a.for each 5o increase in seed
storage temperature
 b. for each 1% increase in seed
moisture content “
rice seeds held in airtight storage
outlive seeds held in open storage
provided they are adequately dried
before they are placed in airtight storage
…..Rice seeds dried by high heat before
sealing were dead after 26 to 28 years,
but seeds dried by the sun to 11-13 %
MC were stored safely for 30 years”
“…
(Kondo and Okumura, Japan 1930-1932)
Methodology
STORAGE METHODS
Plastic material : Polyvinyl chloride
Hermetic storage
Capacity
: 7.5 cu m
Dimension
: 2.95x 1.70 x 1.5m
Thickness
: 0.80 – 0.85mm
Color
: White
Fabrication
: HF welded
Methodology
BUILDING OF EXPERIMENTAL PILES
GrainPro Cocoon
Bottom section
Loading/piling
Top section
Zipper keys
Weighing
Height capacity
Complete set-up
Salient Findings
OXYGEN CONCENTRATION
21.0
20.0
19.0
Cocoon1
Cocoon2
Cocoon3
18.0
Oxygen concnetration, %
17.0
16.0
15.0
14.0
13.0
12.0
11.0
10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Storage durations, weeks
Salient Findings
TEMPERATURE
Ambient
HS
CRS
ACRS
CTRL
34.0
32.0
30.0
Temperature, °C
28.0
26.0
24.0
22.0
20.0
18.0
16.0
14.0
12.0
10.0
1 2 3 4 5 6 7 8 9 1011 12 13 14 1516 17 18 19 20 2122 23 24 25 2627 28 29 30 3132 33 34 35 36
Storage duration, weeks
Salient Findings
RELATIVE HUMIDITY
Ambient
HS
CRS
ACRS
CTRL
90.0
85.0
Relative humidity, %
80.0
75.0
70.0
65.0
60.0
55.0
50.0
45.0
40.0
1 2 3 4 5 6 7 8 9 10 11 1213 14 1516 17 1819 20 2122 23 2425 26 2728 29 3031 32 3334 35 36
Storage duration, weeks
Salient Findings
SEED GERMINATION
100.00
Seed germination, %
95.00
90.00
85.00
80.00
75.00
70.00
0 Month
3 Months
6 Months
9 Months
HS
96.16
96.47
93.30
86.15
CRS
96.80
97.57
92.95
89.60
ACRS
94.30
94.75
88.13
85.82
CTRL
92.87
92.92
76.38
74.70
Salient Findings
SEED VIGOR
100.00
95.00
90.00
85.00
Seed vigor, %
80.00
75.00
70.00
65.00
60.00
55.00
50.00
45.00
40.00
35.00
0 Month
3 Months
6 Months
9 Months
HS
93.40
66.00
77.92
68.20
CRS
94.05
70.90
75.85
67.55
ACRS
92.75
66.30
68.92
63.95
CTRL
90.98
40.13
38.45
36.43
Salient Findings
MOISTURE CONTENT
11.00
10.80
Moisture content, %
10.60
10.40
10.20
10.00
9.80
9.60
9.40
9.20
9.00
0 Month
3 Months
6 Months
9 Months
HS
10.10
10.92
10.66
10.42
CRS
10.45
10.86
10.60
10.39
ACRS
10.18
9.81
9.91
9.52
CTRL
9.55
9.83
10.21
10.18
Summarizing
 Under HS conditions germination can be preserved for
long time. Longest track record is 14 months
 HS performs better than AC storage and almost as good
as cold storage
 Seed vigor is kept high
 Findings of trials with other GrainPro products as
SuperGrainbags, GrainSafes show same results as
GrainPro Cocoons
 Results with maize, sorghum, soybeans are similar
THANK YOU !
GrainPro Inc 200 Baker Ave, Suite 309, Concord MA
01742, USA
Tel.+1-978-371-7118 Fax +1-978-371-7411
sales@grainpro.com
GrainPro Philippines Inc : Subic Bay Gateway Park
salesasia@grainpro.com
Tel.+63-47-2527884 Fax +63-47-2527885
www.grainpro.com
Data: Research By GrainPro, Philrice and Philmec 2006