Background: The cultivation of ginseng (Panax ginseng C. A. Meyer) in greenhouses could reduce the use of pesticides and result in higher yield; however, construction costs are problematic. The adaptation of direct-sowing culture in greenhouses could reduce the cost of ginseng production. Methods and Results: To improve seedling establishment in direct-sowing culture, effects of sowing density (SD), number of seeds sown per hole (SN), and thinning (TH) treatment on the root yield were investigated after 3 years of seeding. The emergence rate was significantly influenced by SD, but not by SN or TH. Damping-off and rusty roots increased with an increase in SN with diminishing effects of SN on seedling establishment. Root weight and diameter were affected by SD, SN, and TH, however, there were no statistical significances. The total number of roots harvested per unit area increased with increasing SD and SN, and the weight of roots was affected by SD, but not by SN or TH. Conclusions: Multi-seed sowing per hole and/or thinning might not be an efficient method for the direct-sowing culture of ginseng. The SD for direct seeding culture in greenhouses should be approximately 33 - 42 seeds/㎡ for an optimum yield of 3-year-old ginseng.

This study was performed to investigate the effects of sowing density and number of seeds sown on the emergence rate and growth characters of Panax ginseng C. A. Meyer under direct sowing cultivation in a blue plastic greenhouse. Ginseng seedlings, derived from seeds sown directly at different densities (90, 108, 135, and 162 seeds per 162m2), were cultivated in sandy loam soil within a blue plastic greenhouse. In contrast to the emergence rate, which decreased with an increase of sowing density, number of survival plant showed an increasing trend. Interestingly, the emergence and number of survival plant were significantly enhanced when 2 or 3 seeds were sown per hole compared with when one seed was sown per hole. Growth of the aerial parts of ginseng were not markedly influenced by sowing density or the number of seeds sown. However, chlorophyll content (SPAD values) increased with an increase in sowing density. Root parameters, such as root length, diameter, and weight, and the number of lateral roots decreased with an increase in sowing density, but were not noticeably influenced by the number of seeds sown. Total saponin content was the highest in the treatment plot containing 135 seeds. Similarly, the content of each ginsenoside was also tended to be higher in this treatment than in other treatment plots. On the basis of the results obtained in this study, it was possible to determine the optimal sowing density and seed number for the direct sowing cultivation of ginseng in blue plastic greenhouse.

The purpose of this study was to establish the proper sowing time and planting density of cowpeas for labor-saving cultivation. Experiments were carried out in Naju, Jeonnam Province (Latitude 35° 04' N, Longitude 126° 54' E) during 2012 and 2013. The intermediate-erect type strains used in this study were Jeonnam1 and Jeonnam2. Sowing was performed five times between June 25 and August 5 at approximately 10-day intervals in order to establish proper sowing time, and sowed at 5,000, 10,000, 15,000, and 20,000 plants per 10a to establish proper planting density. The days from sowing to first flowering was shortest (32 days) in plants sowed on July 25 and became longer for plants sowed on or around July 25. The days from sowing to first flowering was longest (41 days) in plants sowed on June 25. The days from first flowering to first maturing was shortest (8 days) in plants sowed on June 25 and, became considerably longer at later sowing dates. The days from first maturing to first harvesting ranged from 8 to 10 days, with little difference among the sowing periods. Plants sowed on August 5 harvested at the same time, and plants sowed between June 25 and July 25 were harvested either three or two times. The yield was highest in plants sowed on July 25: 209 kg/10a was harvested for Jeonnam1 and 221 kg/10a for Jeonnam2. Furthermore, harvested at the same time enabled when the harvesting was delayed for around 15 days because the share of the seeds first harvested was highest (91%). The proper planting density was estimated to be 15,000 plants/10a, showing the highest yields of 199 kg/10a for Jeonnam1 and 224 kg/10a for Jeonnam2.

This study was carried out to investigate the physicochemical characteristics of 3-year-old ginseng (for Samgyetang product) cultured by various seeding density in direct-sowing culture. Ginsengs were cultured by the seeding density, 275, 300, 330 352 and 396 seeds per Kan, 180×90cm area. Survived rate (82.1%) were the highest in plot of 352 seeds sowed, length and leaf width were high in plot of 300 and 352 seeds. Root yield grain was increased with increase of the seeding density in direct-sowing culture except 352 seeds sowed. Average root weight and diameter were the highest in plot of 352 seeds sowed, 31.6 g and 18.4 mm, respectively. Crude saponin and each ginsenosides content were the highest in plot of 275 seeds sowed. Rg1 content was decreased, Rc and Rb2 content were increased with increase of the seeding density. Total soluble sugar content was the highest in plot of 330 seeds sowed and the lowest in plot of 396 seeds sowed, and oligo- and disaccaride content were high in plot of 330 and 352 seeds sowed. Reological characteristics of ginsengs cultivated according to various seeding density, hardness and springness were high and maximum fracture force was low with decrease of the seeding quantity.

In autumn, to determine the optimal planting date and plant density of rapeseed in southern areas of Korea, Yudal variety for autumn sowing, the highest yielding variety was grown under three different planting dates and five different plant densities. Yield components such as plant height, ear length, number of seedling stand per m2, number of branches and pod length were highest at the plots with Sep. 30 of planting date and 30/20 cm drilling of plant density. Yield of seed, oil and 1,000 grains weight were highest at the Sep.30 of planting date and 30/20 cm drilling of plant density. Judging from the results reported above, at optimum planting date and plant density of rapeseed seemed to be Sep.30 of planting date and 30/20cm plant density in autumn sowing.

In spring, to determine the optimal planting date and plant density of rapeseed in southern areas of Korea. Taiwan#1 variety for spring sowing, the highest yielding variety was grown under five different planting date and plant density. Yield components such as plant height, ear length, number of seedling stand per m2, number of per ear and seed set percentage were highest at the plots with Mar. 5 of planting date and 50/20cm drilling of plant density. Yield of seed, oil, gas and 1,000 grains weight and erucic acid content were highest at the Mar. 5 of planting date and 50/20cm drilling of plant density. Judging from the results reported above, at optimum planting date and plant density of rapeseed seemed too be Mar. 5 of planting date and 50/20cm plant density in spring sowing.

백하수오 근수량 증대를 위한 밀식 재배법을 확립하고자 직파와 육묘 이식으로 구분하여 파종하고 재식밀도를 달리하여 시험을 수행한 결과를 요약하면 다음과 같다. 1. 지상부 생육은 파종 방법 간에는 육묘 이식재배에서 양호하였으며, 재식밀도 간에는 밀식할수록 만장과 분지수는 길거나 많았으나, 엽장과 엽폭은 소식할수록 증가하는 경향이었으며, 개체당 엽수는 22주/m2 에서 가장 많았다. 2. 지하부 생육은 파종 방법 간에는 육묘 이식재배에서 양호하였고, 재식밀도 간에는 주당 지근수, 근장 및 근태는 소식할수록 많거나 길거나 굵었으나, 단위 면적당 지근수는 밀식할수록 증가하였다. 3. 생근수량은 직파 재배보다 육묘 이식재배에서 많았으며, 재식밀도 간에는 밀식할수록 많아 육묘 이식 17주/m2 (1,680 kkg/10a)에 비하여 27주/m2 (2,567 kg/10a)에서 53%증수되었다.

황기의 기계파종(機械播種)에 의한 성력효과(省力效果)와 적정재식밀도(適正栽植密度)를 구명(究明)코자 인력파종기(人力播種機)((주)한국(韓國)고바시)를 이용(利用)하여 조간(條間) 3조(30cm) 4조(25cm) 5조(20cm) 6조(15cm)로 하고 주간(株間) 5cm, 10cm, 15cm로 파종(播種)한 결과(結果) 다음과 같은 결과(結果)를 얻었다. 1. 인력파종기(人力播種機)로 파종(播種)했을때 관행파종(慣行播種)보다 파종량(播種量)이 절감(節減)되었고 파종시간(播種時間)은 관행(慣行) 33. 0시간(時間)/10a에서 3. 5시간(時間)/10a으로 크게 절감(節減)되었으며 89. 4%의 성력효과(省力效果)가 있었다. 2. 기계파종(機械播種)이 관행파종(慣行播種)에 비해 입모수(立毛數)가 17% 증가(增加)되었고, 재식밀도별(栽植密度別) 지상부(地上部) 생육(生育)은 조(條) 주간거리(株間距離)가 커질수록 양호(良好)하였고, 지하부(地下部) 생육(生育)은 조(條) 주간(株間) 거리(距離)가 넓어질수록 근경(根徑), 건근중(乾根重)이 커지는 경향(傾向)이 었지만 근장(根長)은 별차이(別差異)가 없었다. 3. 기계파종시(機械播種時) 재식밀도(栽植密度)는 조간(條間) 15cm (6조) 주간(株間) 10cm에서 주당(株當) 건근중(乾根重)이 3. 6g이며 수량(收量)은 136. 1kg/10a으로 가장 양호(良好)하여 황기의 1년생(年生)으로 수확(收穫)할 경우 적정(適正) 재식밀도(栽植密度)는 조간(條間) 15cm, 주간(株間) 10cm가 가장 적합(適合)한 것으로 나타났다. 4. 관행(慣行)과 기계파종(機械播種)의 경제성(經濟性) 분석(分析)에서도 조수입(粗收入)은 관행(慣行)이 1, 566천(千)원/10a에 비해 기계파종(機械播種)이 1, 933천(千)원으로 23% 증가(增加)되었고 경영비(經營費)는 관행파종(慣行播種)의 494천(千)원/10a 보다 18% 절감(節減)되어 전체(全體) 소득(所得)은 관행파종(慣行播種)의 1, 072천(千)원/10a에 비해 기계파종(機械播種)이 1, 527천(千)원/10a으로 42% 소득(所得)이 증대(增大)되었다.

잇꽃의 안전다수확(安全多收穫) 재배기술(栽培技術) 확립(確立) 일환(一環)으로 경기도농촌진흥원특용작물시험국장(京畿道農村振興院特用作物試驗國場)에서 중북부지역(中北部地域) 파종기(播種期) 설정(設定)과 P.E. 피복(被覆) 재배(栽培) 및 적정(適正) 재식거리(栽植距離) 를 구명(究明)코자 시험(試驗)한 결과(結果)를 요약(要約)하면 다음과 같다. 1, 파종기(播種期)가 10일 빠를수록 출아소요일수(出芽所要日數)는 3~4일(日), 개화기(開花期)는 2일(日), 성숙기(成熟期) 1~2일(日) 빨랐고 주당화두교(株當花頭敎)와 화두당립수(花頭當粒數)가 많았으며 100립중(粒重)도 무거웠다. 2. 파종기별(播種期別) 종실수양(種實收量)은 조파(早播)할수록 많아 파종적기(播種適期)는 해빙직후(播種適期)인 3월(月)20일(日)경(頃)으로 10a당(當) 종실수양(種實收量)은 86.0kg이었다. 3. P.E.피복(被覆) 재배(栽培)는 무피복(無被覆)에 비(比)하여 출아기(出芽期), 개화기(開花期)가 2~3일(日)빠르며, 주경장(主莖長), 분지장(分枝長)이 길고 주당분지수(株當分枝數)도 많은 경향(傾向)이었다. 4. P.E.피복(被覆)이 무피복(無被覆)보다 m2당(當) 주수(株數)와 주당화두수(株當花頭數)는 많아 통계적(統計的) 유의차(有意差)가 인정(認定)되었고 재식거리간(栽植距離間)에는 모든 수양구성요소(收量構成要素)가 유의차(有意差)를 보였다. 5. 10a당(當) 종보수양(種寶收量)은 P.E.피복(被覆)이 무피복(無被覆)(177,9kg/10a)에 비(比)하여 20% 증수(增收)되어 P E.피복재배(被覆栽培)가 유리(有利)하였고, 조간거리(條間距離) 70+30cm 2열(列)로 할때 주간거리(株間距離)는 무피복(無被覆) 재배시(栽培時) 10cm (20천주(千株)/10a) , P.E.피복 재배시(被覆 栽培時) 15cm (13.3천주(千株)/10a)가 적정(適正) 재식거리(栽植距離)로 생각된다.