播種期, 育苗日數 및 播種量 差異가 水稻의 苗素質, 出葉 및 收量性에 미치는 影響 : (第1報) 苗素質에 대하여 = The Effect of Seeding Date, Nursery Period and Seedling Density on the Characters of Seedling, Leaf Appearance Cycle, Yield and its Components of Paddy Rice

다국어 초록 (Multilingual Abstract)

This experiment was conducted to contribute to the safety maximum yield of rice by studying the characters of rice seedlings of recently released variety "Tongil" compared with current leading variety "Jinheung" in accordance with different seeding date (Apr. 13-Early, Apr. 27-Ordinary, May 11-Late), nursery period (28, 42, 56, 70 days in each seeding date) and seedling density (0.3ℓ, 0.6ℓ, 0.9ℓ per 3.3㎡ in each nursery period) in 1972. The results obtained in this study are summarized as follows:
1. The characters of non-irrigated seedling of early seeding were superior to full-irrigated seedlings of ordinary and late seeding from the viewpoint of plant height, number of tillers, top dry weight, dry weight per plant height ratio and rooting activity in both varieties. At the same time the nursery period produced seedlings of the best character was 56 days in variety Jinheung at any seeding date whereas 70 days when seeded early, 56 days and 42 days when seeded ordinary and late respectively in variety Tongil. In other words, the nursery period produced seedlings of the best character in variety Tongil was shortened by delaying the seeding date.
2. The effect of sparce-seeding on the characters of rice seedlings was more remarkable in variety Tongil rather than variety Jinheung, while the characters of both varieties were similiar or rather poor in variety Tongil than Jinheung when seeded densely.
3. The completion date of flag leaf appearance was almost same in spite of different seeding date and seedling density in both varieties. But the number of leaves on main stem was decreased and the leaf appearance interval, the turning period of leaf appearance cycle were delayed in accordance with late seeding and dense seeding.
4. In the case of seeded sparcely, the seedling had no changes of its number of leaves on main stem in accordance with various seeding date and seedling density, and was shortened leaf appearance interval,' increased the number of leaves at turning period of leaf appearance cycle than densely seeded seedling.
Variety Tongil had emerged a bit more leaves on main stem, at the same time was shortened leaf appearance interval and increased the number of leaves on main stem at the turning period of leaf appearance cycle than variety Jinheung.