바이러스 무병묘 정식시기 및 재배기간이 씨고구마 수량에 미치는 영향

Sweet potato is a vegetative propagation crop, and if the same seed sweet potato cultivates for the long term, the yield and quality of sweet potato decrease due to intensified virus infection. Recently, the demand for virus-free sweet potato seedlings has been increasing to the farmers, but the production and supply of virus-free seedlings are insufficient in Korea. Therefore, we investigated the yield of virus-free seed sweet potato in different planting time and cultivation period. Proliferated seedlings derived from meristem culture was examined in this experiment. For planting time 4 varieties (‘Shinyulmi’, ‘Jinhongmi’, ‘Pungwonmi’, ‘Hogammi’) and for cultivation period 3 varieties (‘Shinyulmi’, ‘Pungwonmi’, ‘Hogammi’) were used. Plants were planted in late May, mid-June, and early July in 2015 and 2016. The cultivation period was analyzed when harvested at 110, 120, and 130 days after planting in mid-May in 2017 and 2018. Virus infection rates were determined by RT-PCR using pre-harvest leaves. The yield of 100~300 g tuber size suitable for seed sweet potato was increased in all four varieties cultivated in June. Although late planting in early July, produced 1,799~2,043 kg 10a-1 except 1,390 kg 10a-1 of ‘Dahomi’. ‘Pungwonmi’ and ‘Hogammi’ cultivar showed a higher yield of seed sweet potato in the longer cultivation period. The infection rate of SPLCV on ‘Dahomi’ was 13.3% in May and 6.7% on ‘Pungwonmi’ in June 2016. ‘Jinhongmi’ and ‘Dahomi’ infected with SPFMV was 6.7% and 13.3% in May and ‘Shinyulmi’ was 6.7% in June 2016. In the future, we hope to cultivate seed sweet potato produced by virus-free seedling cultivation year by year and investigate the yield and virus infection level to set up the seed sweet potato renewal cycle.