한국산 나선선충(Hoplolaimidae)을 조사하던 중 Helicotylenchus cavensessi Sher, 1966, Helicotylenchus paraplatyurus Siddiqi, 1972, Rotylenchus alius Van den Berg, 1986 그리고 Rotylenchus incultus Sher, 1965 등 4종이 우리나라 미기록종으로 확인되어 보고한다.

Background : study of long yam and short yam (Dioscorea. opposita) are cultivated in temperate regions but tropical yam (Dioscorea alata) are mainly grown in Africa and sub-tropical regions cultivated crops. Recent tropical yam cultivation area of Korea increased but lack the proper cultivation techniques to climate warming. This study was conducted to elucidate the effect of the timely harvest on Tropical yam at 2015 in Institute of Bioresources Research, GBARES. Methods and Results : Tuber of tropical yam were cut as 40 g, and dust-coating sterilized with lime. Seedlings were grown in heating wire installed seed bed from 11. March to 16. May. Experimental field were fertilized 2,000 kg compost, 34 kg N2, 28 kg P2O5, and 28 kg K2O. All amount of compost and P2O5 treated as basal fertilizer. N2 and K2O treated 14 and 10 kg of basal fertilizer, and 20 and 18 kg of additional fertilizer, respectively. Tillage, covering black PE film with 60×25 cm spacing holes on 120 cm row were conducted. Emergence days from 6. April to 18 May until 28 days to 36 days but 15. June and 9. June were each 19 and 7 days. Dry weigh in early stage due to seedling date, while seedling date according from 6. April to 18. May had no difference. seedling date was not effective on total number of tuber but number of marketable tuber (over 200 g). Marketable tuber number of seedling date according to 20. April was increased 35~132% as 4,028 number per 10 a. And tuber with 20. April was 13~73 g heavier. Tuber yield and marketable tuber yield of seedling date as affected by 20. April were respectively 2,518 and 1,273 kg per 10 a compared to 6. April and from 4. May to 15. June as 1,743~2,457 kg and 484~1,027 kg. Conclusion : Tropical yam is low temperature in the cultivation of Korea but also adverse environmental conditions. Frost is not mature enough off before harvesting. Yam had significant increased marketable tuber (over 200 g) yield due to seedling in mid-April Requires cultivation technology.

Background : Recently, there is a urgent demand for development of new varieties with enhanced resistance to various biotic/abiotic stresses. In order to develop ginseng varieties with such traits, systematic breeding program and comprehensive field studies are prerequisite. Methods and Results : ‘Cheonmyeong' seeds were collected in 2008 from the farmer field of Buyeo. Physiological investigation and propagation were conducted from 2009 to 2011. It was given the name 'Eumseong No. 8 through the observed yield trial from 2012 to 2013 and local adaptability was carried out from 2014 to 2015. All phenotypes including agronomic characteristics, seed yield, and physiological response to biotic/abiotic stresses were investigated according to the ginseng GAP and UPOV guidelines. Yellow-red leaf and pink berry at maturing stage were observed. The time of emergence, flowering and berry maturity of the ‘Cheonmyeong’ were faster than those of ‘Chunpoong’. Stem length of ‘Cheonmyeong’ was shorter than that of ‘Chunpoong’, whereas stem diameter was thicker than that of ‘Chunpoong’. Main root length was shorter but main root diameter is thicker than that of ‘Chunpoong’. Number of seeds of ‘Cheonmyeong’ was fewer than that of ‘Chunpoong’ but 1,000-seeds weight and stratification rate were higher than those of ‘Chunpoong’. The yield performance of this variety was 661 kg/10 a in local adaptability test for two years, which is 22% higher than that of ‘Chunpoong’. ‘Cheonmyeong’ showed strong resistance to phytophthora blight, mulberry mealybug and nematode and moderate resistance to alternaria blight. ‘Cheonmyeong’ did almost not occur yellow spot of aerial part and rusty skin of root, show moderate resistance at high temperatures. Conclusion : Our study demonstrated that ‘Cheonmyeong’ is an ideal variety with heavier root weight and enhanced stress resistance and contribute will enhance biotic/abiotic stress resistance and increase the farmers' income.

Background : This study was carried out to understand the effect of seedling weight (SW) on growth and flowering in Panax ginseng. Methods and Results : The testing materials were Chunpoong (CP), Yunpoong (YP) and Jakyeongjong (JK). The increase of seedling (1yr) weight led to an increase in ratio of flowering plant and in number of flower per plant. The seed setting rate of two year-old plant (CP, YP, JK) increased with increase of SW at the planting time (PT) and number of flower per plant of three year-old plant (CP, YP) increased also. In the two year-old plant (JK), the ratio of three leaves per plant was 8.8, 19.6, 31.0, 42.0, 44.7 and 58.2%, respectively, in the SW of >0.6, 0.6~0.8, 0.8~1.0, 1.02~1.2, 1.2~1.4 and 1.4g<. The growth of ginseng plant was good with increase of SW at the PT. Conclusion : There was a highly positive correlation between seedling weight and flowering characteristics.

Background : Yam absorbs nutrition and water through water absorptive root generated from head of rhizome. Round-shaped yam (RSY, Dioscorea opposita) and tropical round-shaped yam (TRSY, Dioscorea alata)are more sensitive to drought because of shorter head of rhizome and shallower root compared to long yam or short yam. This study was conducted to elucidate the effect of irrigation on RSY and TRSY yam at 205 in Institute of Bioresources Research, GBARES. Methods and Results : Tuber of RSY and TRSY were cut as 40 g, and dust-coating sterilized with lime. Seedlings were grown in heating wire installed seed bed from 25. March to 16. April. Experimental field were fertilized 2,000 kg compost, 34 kg N2, 28 kg P2O5, and 28 kg K2O. All amount of compost and P2O5 treated as basal fertilizer. N2 and K2O treated 14 and 10 kg of basal fertilizer, and 20 and 18 kg of additional fertilizer, respectively. Tillage, installation of drop-watering tapes, and covering black PE film with 60×25 cm spacing holes on 120 cm row were conducted. 20 L per m2 was irrigated 7 days interval except rainy day from middle of May to late of September. RSY had high emergence rate in early stage due to irrigation, while TRSY had no difference. Irrigation was not effective on total number of tuber but number of marketable tuber (over 200 g). Marketable tuber yield of RSY according to irrigation was increased 89% as 1,147 kg per 10 a. And tuber with irrigation was 73 g heavier. Tuber yield and marketable tuber yield of TRSY as affected by irrigation were respectively 2,611 and 1,715 kg per 10 a compared to control, 1,462 and 428 kg. And irrigated tuber was 66 g heavier. Conclusion : TRSY had more effective on irrigation than RSY. Both of yam had significant increased marketable tuber yield due to irrigation. Therefore RSY and TRSY are necessarily irrigated because of those absorptive characteristics, short head of tuber and shallow root.