Unlocking the hermetic and traditional storage potential in preserving sorghum (Sorghum bicolor L. Moench) in community-based seed systems under semi-arid Zimbabwe

Sorghum (Sorghum bicolor L. Moench) is a climate-smart crop contributing to food and nutrition security in semi-arid areas. Harvest retention as seed is widespread in sub-Saharan Africa. However, few field evaluations on sorghum seed storage under smallholder conditions exist in farmer-managed seed systems. Community-based experiments in Mudzi (2023-2024), evaluated hermetic and traditional storage methods in maintaining sorghum seed quality. Using homogenised farmer-saved seed in a randomized block design, we evaluated metal silos, PICS bags, synthetic pesticide, cowdung ash, and untreated control. Samples were collected at 8-week intervals for 32 weeks and assessed for: insect seed damage (ISD), weight loss (WL), insect counts, insect feeding dust and exuviae, moisture and germination. Significant differences (p < 0.05) occurred among treatments and storage durations for all parameters. ISD ranged from 1.7 to 3.8% in hermetic and 1.8 to 4.2% in non-hermetic treatments, while WL was < 2% in all treatments. PICS bags and cowdung ash had the least damage levels. Post-storage germination was 82.9-91.3% and 77.3-92.1% for hermetic and non-hermetic treatments, respectively. Correlations were found among seed quality parameters and environmental variables. Moisture content and total insect counts were highest in metal silos. Dominant species were Tribolium castaneum and Sitotroga cerealella. PICS bags are alternatives to conventional methods for preserving sorghum seed under semi-arid conditions. Cowdung ash offers a sustainable seed storage alternative climate-resilient solution under community-based seed banks. Longer term storage evaluations are recommended given the key role of community seed banks to conserve seed semi-arid conditions.