Low-cost seed storage technologies for development impact of small-scale seed saving entities in tropical climates

Abstract

Summary Seeds can deteriorate rapidly under high heat and humidity, making it challenging and potentially costly to store orthodox seeds effectively in the tropics, thereby affecting agriculture development. This work explores the effectiveness of novel, low-cost technologies for storing seeds in warm, humid, resource-constrained environments, focusing on maintaining the viability of seeds already dry prior to storage. Seeds of okra (Abelmoschus esculentus (L.) Moench), sorghum (Sorghum bicolor (L.) Moench), and velvet bean (Mucuna pruriens (L.) DC) were kept for 12 months under roofed, outdoor screened porches. Seed moisture content prior to treatment was 6, 9, and 12% for okra, sorghum, and velvet bean, respectively. Treatments, replicated four times at each of two locations (USA [Florida] and Thailand), were technology suites involving vacuum drawn on glass jars with a modified bicycle pump, vacuum drawn on polyethylene bags with an electric vacuum sealing machine, desiccant (calcium oxide powder or zeolite Drying Beads® at a 2:1 ratio, by weight, of seeds to desiccant) in glass jars, and nontreated seeds in paper bags. Ambient temperature and humidity were variable and high, reaching over 35 °C and 83%, respectively, at both locations. Under these conditions, okra and sorghum germination percentages (across locations) without treatment declined from over 90% initially to 30 and 0%, respectively, by month 12. Both vacuum treatments and calcium oxide maintained high germination of okra (≈ 80%) and velvet bean seeds (nearly 100%) across locations. Glass, however, was superior to polyethylene in maintaining vacuum and stabilizing the moisture content of okra and sorghum seeds. Only zeolite reduced seed moisture below initial values, drying seeds to ultradry levels of <5%. With zeolite, sorghum germination stayed near 70% over time, while okra and velvet bean germination fell to <40 and <20%, respectively, by month 12, suggesting that, with the beads kept with dry seeds in storage rather than removing the beads after reaching a target level of seed moisture, the 2:1 ratio of seed-to-bead weight was too high for seeds that are sensitive to ultralow moisture. Findings have practical implications for inexpensive household- or community-level seed storage to deliver development impact.

Identification of DNA Methylation Changes in European Beech Seeds during Desiccation and Storage

“…Conservation of seeds is the primary method of choice when attempting to preserve the gene pool of a plant species [ 20 , 30 , 33 , 34 , 35 , 36 ]; therefore, deterioration of seeds during storage has profound influences on agriculture and conservation efforts [ 37 ]. Seed aging processes resulting in viability decline and final decrease of plantlet amount are dependent on storage conditions, which are the temperature and RH that determine seed MC.…”

A Review on Seed Storage Technology: Recent Trends and Advances in Sustainable Techniques for Global Food Security

“…Innovative drying techniques, such as low-energy methods, are necessary for reducing seed moisture to levels suitable for long-term storage. Trail et al (2021) found that storing seeds in dry, cool, and low-oxygen conditions slows seed metabolism, prolonging storage life. The significance of low-cost technologies for drying seeds is highlighted, particularly in tropical environments where high humidity and heat pose significant challenges to seed storage.…”

“…These methods help maintain seed quality by creating an environment that minimizes oxygen and moisture levels. The use of desiccants and vacuum sealing has also been proposed to maintain seed quality in climate-controlled seed banks (Trail et al, 2021).…”

Effect of Storage Period on Seed Germination in different Promising Lines of Bambara Groundnut (Vigna subterranea (L.) Verdc)

“…At the time of storage, humidity, temperature, and the proportion of oxygen are the main environmental factors that influence seed deterioration [9]. Storing seeds longer than 1 year becomes a challenge even where seeds are saved, stored, and planted on short annual cycles [10].…”