ECHO Development Notes #126 Now Available

Excerpt: Bicycle Pump Vacuum Sealer for Seed Storage

Storing seeds in the tropics can often be difficult; with high temperatures and humid conditions, seeds lose their ability to germinate quickly. Many techniques for seed storage exist, from the high-tech standards of gene banks to simple methods used by villagers for saving their own seeds. All have their strengths and weaknesses, but when balancing costs and resources, which methods are really the most effective? This article highlights research conducted by ECHO Asia regarding the use of vacuum sealing, using a simple bicycle tire pump, for tropical seed storage under resource-constrained settings.

The three key factors that determine the rate of seed deterioration in storage are: oxygen pressure (amount of oxygen with the seeds in storage), seed moisture content, and temperature (Roberts, 1973). An increase in any of these factors will lower the storage life of the seeds, and as a general rule any increase of 1% moisture content or 10°F (5.6°C) in storage will halve the storage life of the seeds (Bewley and Black, 1985). Each factor contributes to seed decay in specific ways, and minimizing these conditions is critical to effective seed storage. Vacuum sealing is a relatively low-cost method that requires few inputs after an initial investment. Sealing helps conserve seed quality by minimizing oxygen presence and exposure to ambient humidity, thereby keeping seed moisture content low.

Historical perspective (Dr. Tim Motis and Dr. Abram Bicksler)

ECHO’s initial exposure to the use of bicycle pumps for vacuum seed storage came from a writeup sent to our Florida seed bank by development worker, Patrick Lahr. Based on that writeup, Dr. Tim Motis modified a bicycle pump to demonstrate the concept of vacuum sealing at the ECHO Florida Seedbank. A similar pump was also constructed at the ECHO Asia Seedbank by Niemeet Chompoothong, with further improvements made by Brock Mashburn to create a more usable machine (Pictured Above) that is able to create a better vacuum in a jar containing the seeds. [...]

Read all of EDN 126 including:

• Selenium and Human Health
• From ECHO’s Seed Bank: Sorghum Pollination 
• ECHO South Africa Research Update
• Books, Websites and Other Resources
• In Memoriam: Dr. Frank Martin
• Upcoming Events