A Study on Productivity of Forage Turnip ( Brassica rapa var. rapifera )

사료용 순무의 생산성에 관한 연구

A series of experiments were carried out for two successive years to investigate the productivity of forage turnip in mid-northern area of Korea. Fresh matter and dry matter yields of 6 foreign cultivars (Purple Top Strap Leaved, Purple Top White Globed, Seven Top, Shogoin, White Egg and Amber Globe) seeded either in early spring or in autumn after harvesting forage corn were evaluated with different seeding date and harvesting date as well as with different level of fertilization. The results obtained are summarized as follows: 1. The earlier the seeding date in spring (Mar. 29, Apr. 12, Apr. 16) was, the higher was the yield of fresh matter and dry matter as the plant growth ceased after mid June, when the temperature began to rise. 2. In spite of its high DM yield, the Japanese cultivar, Shogoin, showed poor forage quality for summer feeding due to its earlier bolting in harvesting season. 3. Of the 6 cultivars Purple Top White Globed showed highest DM yield (800 kg/ 10a) in mid area including SEOUL irrespective of planting season. 4. Although the turnips showed mostly positive yield responses to fertization, the differences were not great especially above the level of$N-P_2O_5-K_2O$: 5-3-4 kg/lOa. 5. IN TAEGWALLYONG, a northern area of Korea, the average fresh matter yield of the six cultivars tested amounted to 3,500 kg/lOa when drilled on June 30 and harvested on Aug. 30, although bulb formation during the summer was relatively poor. 6. Concluded, forage turnip is regarded to be a suitable catch-crop which has the potential to maintain and increase the total forage production in mid-northern area of Korea. The intercropping is recommendable especially for autumn planting well past the time forage corn has been harvested.