This experiment was carried out to study the effect of elapsed time after air flow cutoff on the germination rate of Italian ryegrass seed with different moisture contents during natural drying on reclaimed land, Jangheung and Kimje of Korea from 2023 to 2024, respectively. Seeds with moisture contents of 15.3, 22.3 and 28.0% were placed in vinyl bag (30 × 40 cm) at storage thicknesses of 10, 15, and 20 cm, and air flow was cutoff for 48 h. Seed moisture content, seed temperature (℃) and germination rate were investigated at 12-h intervals. After 48 h of airflow cutoff during natural drying, seed moisture content did not significantly differ among storage thickness treatment (p>0.05). When Italian ryegrass seeds with moisture contents of 27~28% were stored under conditions with air flow cutoff at 15~20cm thickness for 48 h, the seed temperature reached up to 30℃ and the germination rate was excellent at around 70~80%.
This experiment was carried out to evaluate the effect of natural drying methods on the moisture content and germination of Italian ryegrass seed in Jicheon reclaimed land, Jangheung, Korea, from 2023 to 2024. The natural drying methods tested included seed spread thicknesses of 2.5, 5.0 and 7.5 cm; seed reversal frequencies of 1, 2 and 3 times per day; and two reversal methods: seed-only reversal and complete mixing of seed with a dry mat. The thinner seed spread thickness significantly accelerated moisture content reduction(p<0.001). However, the reduction in moisture contents due to the number and method of seed reversal was minimal, approximately 1%. Seeds initially having around 48.9% moisture content required 2, 4 and 5 days to reach a moisture content of 14% when dried at spread thickness of 2.5, 5.0 and 7.5 cm, respectively. Seeds with an initial moisture content of 23-26% required 1 to 2 days to reach 14% moisture content while maintaining approximately 80% germination rate under the tested natural drying methods. When seeds with an initial moisture content of 48.9% were dried at a spread thickness of 2.5 cm, the germination rate was 74.6%, which was significantly lower than the 83.8 and 81.6% germination rates observed for seeds dried at 5.0 and 7.5 cm thickness, respectively(p<0.002). These results suggest that for faster drying and higher-quality Italian ryegrass seed, harvesting at 30% seed moisture content, utilizing the cultivation field as a seed drying place, and applying a seed spread thickness of 2.5 to 5.0 cm are optimal practices.