It is important to accelerate rooting and establishment of seedlings after transplanting for higher dry matter production and tuber yield in sweet potato cultivation. Therefore, this study was conducted to obtain some information about the effects of vine-cutting holding on rooting and plant growth after transplanting. Vines were cut 20-25cm long and stored for 1, 3, 5, 7 or 9 days in a shade room at 20~pm 0.5~circC , RH 68~pm,/TEX>1%. Peroxidase activity in the vine cuttings increased as the holding period increased and the highest catalase activity was detected in the 5-day holding. Length of main vine, number of branches and nodes on main vine also increased in the 5-day holding. There was little difference in the diameter of main vine among the various holding periods. The data obtained indicate that transplanting of vine cuttings after 5-day holding could promote rooting and vine growth

An extensive investigation has been made for the possible utilization of polypropylene spunbonded fabrics in rice seedling nursery. Considering the cropping systems available in southern part of Korea, sowing dates were fixed at April 5 and April 20 for single cropping and May 6 and May 26 for double cropping. Nursery period was fixed to 35 days for each sowing date. Four different thickness of polypropylene spunbonded fabrics, 40, 60, 80, 100 g/m2 , were tested in rice seedling nursery. The temperature and light intensity were not significantly different among the thickness of polypropylene spunbonded fabrics. Light intensity was significantly reduced in polypropylene spunbonded fabric (72.2 Klux) compared with polyethylene mm (85.5 Klux), however, the reduced light intensity was enough for seedling growth. The temperature in the polypropylene spunbonded fabric covering during low air temperature was higher than that in polyethylene mm tunnel. At transplanting, the rice seedlings grown in polypropylene spunbonded fabric condition was shorter (17cm) but healthier than those in polyethylene mm (23cm). The estimated possible nursery periods using the polypropylene spunbonded fabric covering may start from April 1 at Chinju (plain area in Southern Korea, 20m altitude) and April 15 at Susang (mountainous area, 430m altitude). Labour hours and cost were reduced by about 28% and 48%, respectively.