Enhancing seed conservation in rural communities of Guatemala by implementing the dry chain concept

Seed conservation in rural communities of low- and middle-income countries located in tropical areas is particularly problematic, due to high relative humidity that promotes insect and fungal infestations and leads to rapid losses in seed viability. Seed conservation in those areas is affected by unreliable power supplies that do not allow the use of dehumidifying and refrigeration systems recommended for the long-term storage of seeds. We tested the dry chain, i.e., initial seed drying with a reusable desiccant in the form of zeolite beads followed by seed conservation in hermetic containers, in rural communities of Guatemala (Huehuetenango Department). In this region, a network of community seed reserves (CSRs) has been established to provide a safety backup for seed and to conserve local agrobiodiversity. Using a local maize variety in three communities, we compared the dry chain with the seed conservation methodology employed in the CSRs (i.e., undried seeds in hermetic flasks) as well as with seed conservation in open storage, both in the local CSR and in a farmer’s granary. Seed conserved using the dry chain treatment maintained very high seed viability (> 80%) throughout the whole experiment (6 months) and reduced fungal and insect infestations (< 3%). In the other treatments, the viability declined significantly to an average of 52% non-viable and 19% infested seeds after 6 months of storage. The dry chain was demonstrated to be an excellent solution for enhancing seed conservation in biodiversity hotspots of tropical areas as well as for improving seed security for farmers.