Ruminant pestiviruses of bovine viral diarrhea virus (BVDV) and border disease virus (BDV) are closely related to classical swine fever virus (CSFV) and all belong to the genus of Pestiviruses. BVDV is one of the most important viral pathogen of cattle and has been recorded in most countries where cattle are raised. Natural host for BVDV is cattle, but BVDV is able to infect pigs as well. The purpose of this study was to investigate the prevalence for antibodies against BVDV in domestic pig farms in South Korea from 2009 to 2011. In this study, 2,755 pigs in 239 farms in South Korea's inland and 5,293 pigs in 613 farms in Jeju province (CSF free region) were investigated for antibodies against two pestiviruses, BVDV and CSFV by a virus neutralization test (VNT). The seroprevalences on the individual level and on herd level against BVDV were 5.3 % and 21.2 % in South Korea's inland, 5.2 % and 6.5 % in Jeju province, respectively. Based on the ratio of respective antibody titers by the comparative VNT, 273 pigs in Jeju province with BVDV infection were detected and they were distinctly negative to CSF. It is recognized that porcine infections with BVDV naturally occurred in Jeju province. Whereas, antibody titers against BVDV of South Korea's inland were cross-reactivity with CSFV.

This study was conducted to improve and supplement the system of cryopreservation for adventitious bulbs induced by tissue cultured bulb-scales of lily (Lilium spp.) cvs. ‘Milky way’. The explants, bulblets and bulb-scale-bulblets, were treated to low temperature (4℃) for 7 days prior to the pre-culture. The adventitious bulbs were pre-cultured in Murashige and Skoog (MS) liquid medium supplemented with sucrose (0.3 and 0.7M). The pre-cultured adventitious bulbs were treated to loading solution (LS1 or LS2, C4 or C6) containing 35% of PVS3 (LS1, C4) or 40% of PVS3 (LS2, C6) for 40 min and exposed to dehydration solution (PVS3, B1) containing 50% glycerol and 50% sucrose for 60 min at 25℃. The adventitious bulbs were moved onto droplets containing 3 μl PVS3 on sterilized aluminum foils, and then soaked into liquid nitrogen (LN) for 60 min. The result of highest regrowth rate as 65.7% was obtained in cold treatment (4℃), osmoprotected with LS1 solution, and cultured in PCM3 medium by using bulb-scale-bulblet for cryopreservation. This result shows that droplet-vitrification could be used as a promising method for long-term storage of lily genetic resource.