Question

For a seed lot having 18%moisture content safe temperature limit for drying

Answer 1

Answer:

This research was conducted to determine the moisture contents that give maximum longevity to seeds stored at ambient temperatures in Shijiazhuang, China. Four or five cultivars of flax (Linum usitatissimum L), sesame (Sesamum indicum L), soybean (Glycine max Merr.) and durum wheat (Triticum durum Desf) seeds were dried to moisture contents between 0.5 and 11% (fwb), sealed in air-tight containers, and then stored for 4-5 years at temperatures fluctuating between 0 and 35°C and averaging 18°C. During storage, germination percentage declined from an initial value above 90% to as low as 0% depending on the species, cultivar and moisture content at storage. Storage at high water contents resulted in complete loss of viability within 4 years. Some drying improved the longevity of all samples, but drying to extremely low water contents resulted in reduced longevity of some cultivars of each species. The range of water contents that gave maximum survival varied between species from 7.6-9.7% for wheat to 1.8-2.5% for sesame. It is concluded that there is an optimum water content for seed storage and, for seeds with high oil contents, the value of the optimum is less than the benchmark 5% water content recommended for seed storage by the International Plant Genetic Resources Institute.