Effect of Tunnel Culture on Improvement of Seed Harvesting in Atractylodes macrocephala Koidz.
Background : Bai Zhu (Atractylodes macrocephala Koidz.) has been generally harvested in 1-2 years after seedstock planting. Recently, seed is used increasingly for planting in spring and rhizome is harvested in 1 year. In 1 year open field culture, seed harvesting rate is low below 30% and supply and demand of seed is so hard. This study was carried out to improve seed harvesting for stable seed supply and demand in Atractylodes macrocephala Methods and Results : Seed of Atractylodes macrocephala Koidzumi was directly sown in open field, under tunnel and rain shielding condition in mid-April. Tunnel was installed from prebloom, mid-september to seed harvesting time, November using 240 ㎝ wires for 120 ㎝ by interval and 20 ㎝ by height in furrow to assure insect pollination and wind fertilization. In rain shielding condition, plant height was highest as 38.2 ㎝ and number of branches, number of nodes, and content of chlorophyll were higher as 7.8 ea/plant, 8.7 ea/plant, and 65.4 respectively compared to open field and under tunnel. Flowering time was earliest as 23rd September in rain shielding condition and in open field and under tunnel was 26th September. There is no blossom rot in rain shielding condition while blossom rot occurrence was highest in open field by 5 in degree. Seed setting rate was highest as 42.0% in tunnel cultivation and seed weight per plant and 1,000 seed weight were highest as 3.7 g/plant and 22.3 g respectively. Total seed yield was higher as 58% and 65% in tunnel and rain shield condition respectively compared to 29 ㎏/10 a of open field. Tunnel cultivation for seed production of Atractylodes macrocephala is more beneficial for lower installation cost. Conclusion : Tunnel cultivation for seed production of Atractylodes macrocephala is more beneficial due to low blossom rot degree by 1, higher 1,000 seed weight and seed setting rate as 19.0 g and 42%, increased seed yield, and lower installation cost.