This week I put into motion the major research project I’ve been working on during my time here at ECHO Asia. As I wrote in a post a little while ago, ECHO is comparing different methods for controlling oxygen, temperature and moisture in stored seeds. These methods vary from the fairly high-tech to the pretty low-tech. Here’s a run-down.
We’re testing four different desiccants in this experiment: zeolite beads, zeolite powder, silica beads and parched rice.
Zeolite beads are a relatively expensive new product, which is in development in cooperation with USAID. Silica beads is a somewhat cheaper technology, perhaps familiar to you by its presence in potato-chip bags. Zeolite powder is a product bought on the local market here in Thailand and marketed primarily as a soil amendment, though it also has desiccant properties. Parched rice is simply rice cooked briefly in a dry wok until it puffs up a bit. Some brown parched rice is pictured above.
In addition to the desiccants, we’ve got three kinds of containers: vacuum sealed bags, glass jars sealed with a bicycle pump and bamboo canisters:
Finally we used two different storage rooms, one is the seed bank’s cold room, refrigerated by an A/C unit and insulated with styrofoam. The other is an earth-bag house, built from soil and fertilizer bags, which though not refrigerated does passively modify temperature.
ECHO’s hope is that this experiment will reveal that some inexpensive local technologies, like the parched rice, bamboo canisters, jars sealed by bicycle pump and the earth-bag house, will form part of a package of technologies for small-scale seed banks.
It’s an honor to be part of this experiment, and it feels good to get it kicked off!