본 연구는 2013년 1차 솎아베기 및 가지치기를 시행한 35년생 종가시나무 인공림을 대상으로 2014년과 2021년에 임분조사를 실시하여 임목 생장⋅형질 반응 특성을 분석하였다. 가지치기 시업임분에 대한 솎아베기 강도별 임목생장 특성을 비교 분석한 결과, 평균수관면적은 강도구가 대조구보다 유의적으로 넓으며(p<0.05), 정기생장률도 높아 흉고직경과 유사한 경향을 보였다. 가지치기 시업임분에 대한 솎아베기 처리구별 가지발 달 특성을 분석한 결과, 약도구를 제외한 모든 처리구의 지하고는 가지치기 처리구에서 대조구보다 유의적으로 높게 분석되었다(p<0.05). 고사지 발생률의 경우 가지치기 처리구에서 29.6∼36.7%, 대조구에서 40.0∼53.3%로 각각 나타났다. 활엽수 입목형질등급평가 기준에 따른 연구대상지의 형질등급 분석 결과, 1등급 입목의 비율은 가지치기 처리구에서 21.0%, 대조구에서 11.6%로 각각 나타나 유의적인 차이를 보였으며, 이로부터 가지치기 시업에 따른 임목형질개선 효과에 대한 실증적 시험연구결과를 도출할 수 있었다.

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 conducted to investigate the effects of sowing density, number of seeds sown per hole, andthinning treatment on growth characteristics and disease occurrence in Panax ginseng under direct sowing cultivation in ablue plastic greenhouse. Seedling were grown from 2 or 3 seeds sown, and the healthiest was only retained, while the restwere thinned out at the foliation stage. NO3-N, P2O5, and organic matter content differed significantly between growthconditions in the plastic greenhouse and in conventional shade in the soil. Disease also tended to be higher in the conven-tional shade than in the plastic greenhouse. Plant height and stem length showed an increasing trend with increasing sowingdensity and number of seeds sown per hole. However, these measures noticeably decreased when thinning treatment wasconducted. Growth of the subterranean part of ginseng was not markedly influenced by sowing density, the number of seedssown per hole, or thinning treatment. Root weight, which is an important factor in yield, was significantly affected by thenumber of seeds sown and thinning treatment. Interestingly, root weight tended to be higher in the thinning treatment plotthan the untreated control plot. Damping-off and root rot increased noticeably as the number of seeds sown increased. Dis-ease also tended to be substantially higher in the thinning treatment plot than the untreated control. However, physiologicaldisorder of the plants did not vary with sowing density, the number of seeds sown, or thinning treatment.