• Journal of Advanced Marine Engineering and Technology
• /
• 제27권2호
• /
• pp.280-288
• /
• 2003

We need refrigeration system which can maintain the freshness of agricultural products, because of being distance from a tiller to a consumer. Vacuum Pre-cooling system has an advantage in quality maintenance through vapid cooling down by using latent heat of evaporation of stored products. A number or thawing methods in current use have also several disadvantages in thawing time. discoloration mass loss caused by drying, capital costs and running cost. These damages are, it is claimed, either eliminated or improved by the vacuum thawing system. An experimental study on the pre-cooling for the bean sprouts and cabbage, and thawing for hairtail and croaker by the low temperature vacuum system were carried out. The cabbage cooling time with this Pre-cooling vacuum system took about 60 minutes to reach from $23.2^{circ}C to 4.5^{\circ}C$ at 5 mmHg abs. ($6.66\times10^{-4}$ MPa). The croaker thawing time with this low temperature vacuum thawing system took about 170 minutes to reach from $-10.3^{circ}C to -0.8^{\circ}C$ at 20 mmHg abs ($2.67\tiems10^{-3}$MPa). The vacuum Pre-cooling and thawing system have merits compared with present systems in their short intervals to cool down and to thaw without any quality losses.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.210-210
• /
• 2017

Sorghum is rich source of various phytochemicals including phenolic acids that have potential to significantly impact human health. Phytochemical production may be induced by not only genotype but a number of environmental factors including temperatures and amount of sunshine. The objective of this study was to determine the effect of planting date and harvesting stage on the agronomic and quality traits of 'Donganme' grain sorghum variety developed to produce high antioxidant activity. 'Donganme' were planted in three locations at four dates from early May to early July. Each planted fractions were harvested five times 35, 40, 45, 50, 55 days after head shooting date, respectively. Significant difference existed between the growth period and the agronomic traits. The interaction effects planting date and harvesting date was significant for plant height, tiller production, grain yield and antioxidant activity, indicating that low temperature and integrated sunshine influence on that traits. The result showed that antioxidant activity production occurred when the sorghum crop was grown in late season although the yield is lower. To produce antioxidant activity from sorghum grain need to consider the relation between the yield and nutrition component simultaneously.

• 한국유기농업학회지
• /
• 제6권1호
• /
• pp.127-132
• /
• 1997

This experiment was carried out to examine the effect of various functional materials such as bioceramic podwers, crushed shells and elvanites supplemented to the each substrate on the seedlings growth of rices. The rice seedlings were grown in pots filled with substrates supplemented with bioceramic podwers, crushed shells and elvanites. The growth of rice seedlings in terms of plant height, stem diameter, root length and leaf width, plant fresh and dry weight was promoted by adding the bioceramic powders (2 to 3g/kg), crushed shells (10g/kg) or elvanites (20 to 40g/kg). Plant height was also promoted by the adding of bioceramic powder from 16 days after treatment, whereas crushed shells and elvanites from 10 days after treatment. Especially, root growth was greatly influenced by bioceramic powder, whereas the shoot growth(leaves and stem) was stimulated by the crushed shells and elvanites supplemented into each substrate. In the field, plant growth in terms of plant height, leaf length and leaf width were also influenced by crushed shells and elvanites at 74 days after treatment. The growth of rices in terms of tiller number, spikelets, panicles and spikelets/panicle was incresed by adding the crushed shells and elvanites from 100 to 200g per m2.

• 한국환경복원기술학회지
• /
• 제11권3호
• /
• pp.12-19
• /
• 2008

This study was conducted to investigate the draft data for the habitat environment and massive propagation method of Miscanthus changii, which is classified as rare species. The in-site analysis of the native soil give a indication of pH 5.24~5.48, electric conductivity (EC)0.03~0.02 $dS{\cdot}m^{-1}$, organic matter (OM) 1.13~1.15%, Ca 3.4 $mg{\cdot}kg^{-1}$, K 0.25 $mg{\cdot}kg^{-1}$, Mg 0.53 $mg{\cdot}kg^{-1}$, N 0.23%, P 2.15 $mg{\cdot}kg^{-1}$ showed low and 0.33~9.12 $cmol{\cdot}kg^{-1}$ CEC. Growth and tiller number in rhizome propagation of Miscanthus changii showed that horticulture media (perlite 1+vermiculate 1+peat moss 1) is the most suitable soil to habitat. As for seed propagation, germination percentage is 0% (0/20) at first seeding, 2% (1/50) at second seeding and 2.1% (6/280) at third seeding. The average germination percentage was below 2%. This is the reason why Miscanthus changi disappear at habitat of poor soil environment and low germination. We gained 61 plants that 60 rhizome propagation and 1 by seed propagation, renatural to habitat.

• 한국초지조사료학회지
• /
• 제9권3호
• /
• pp.135-140
• /
• 1989

This experiment was to study the relationship between shoot and root system in perennial ryegrass at different stages of growth. The results are summarized as follows; 1. The dry weight of shoot was significantly correlated with the dry weight of root at both stages of growth. 2. The yield components of shoot and root systems were changed by the stages of growth. Thus, the dry weights of shoot and root were positive correlated with the number of tillers and roots at 60 days after sowing. But, the dry weights of shoot and root were positive correlated with the dry weight of root, the dry weight of tiller, length of plant and length of root at 90 days after sowing. 3. Maprirna variety was obtained a higher dry weights of shoot and root at 60 days after sowing, but, Alta variety was obtained at 90 days after sowing, respectively. 4. The dry weight of shoot was positive correlated with leaf area at both stages of growth. 5. The dry weight of shoot was significantly negative correlated with specific leaf weight at 60 days after sowing, but positive correlated with specific leaf weight at 90 days afikr sowing. 6. The dry weight of root was smcantly positive correlated with leaf area at 60 days after sowing, but not recognized at 90 days after sowing.

• Journal of Ecology and Environment
• /
• 제42권1호
• /
• pp.43-49
• /
• 2018

Iris laevigata is geographically restricted and legally protected in Korea. In this study, a mesocosm study was conducted to examine the effects of environmental conditions such as water levels and soil nutrient conditions on the growth and survival of I. laevigata seedlings. Complete submergence lowered the total number of leaves, biomass, and survival rates. A rise in soil nutrients increased overall seedling growth and increased tiller numbers via the promotion of asexual reproduction. Also, we found that the lowest measured values of seedlings are associated with the most stressful condition due to the interaction of low soil nutrients and high water levels. I. laevigata seedlings, however, are distributed in low-nutrient habitats such as floating mat, even though they do not grow well under these conditions. This study suggests that I. laevigata does not prefer low-nutrient condition but choose another benefit such as low competition. Also, the water level must be lower than the seedling height for effective growth and management of I. laevigata.

• 농업과학연구
• /
• 제47권2호
• /
• pp.305-313
• /
• 2020

Root hair development has the potential to increase crop yields and at the same time to decrease fertilizer use, which will be required in the next 30 years to meet the demand for crop-derived commodities in a world with decreasing available natural resources. Root hair defective six (RHD6) encoding a basic helix-loop-helix transcription factor, is associated with root hair differentiation, and its roles are root hair initiation and elongation. Grass plants, rice and Brachypodium have been used as model plants to study the gene function of the root hair defective six like (RSL) subfamily which is orthologous to AtRHD6. The RSL subfamily has an identical gene function with AtRHD6 which is involved with root hair differentiation as well. Plants with longer root hairs within a species should have an improved Pi uptake efficiency; therefore, we would expect that a plant with a high Pi uptake could contribute to increasing the plant yield. We achieved increased root hair length by manipulating the RSL subfamily genes. It is expected that in these transgenic plants, the long root hairs would be sufficient to improve the Pi uptake and hence improve biomass and yield component (tiller, spikelet number, and spikelet weight) of the plant. Here, we demonstrate that Brachypodium transgenic plants overexpressing the BdRSL subfamily genes have an improved biomass and grain yield. The result of this study could be applied to important crop plants like rice.

• 한국작물학회지
• /
• 제45권5호
• /
• pp.288-293
• /
• 2000

Two rice cultivars (Oryza sativa L.), Hwa-seongbyeo of Japonica type and Taebackbyeo of Indica/Japonica type, were cultivated with hydroponic culture to examine nitrogen effects on the growth responses, contents and utilizations of carbohydrates, and the ripening velocity of grains with three different N levels. Plant height and tiller number were clearly increased to 80 ppm N level compared to 40 ppm N level and then they were slightly decreased in N level of 120 ppm. Higher dry weights were appeared with 80 ppm N level than did with other N levels, showing statistically differences in both cultivars and N levels, while dry weight of roots was heavier with decreasing the N levels. Therefore, T/R ratios were not significantly different among N levels, although there was statistically differences between rice cultivars. After the flowering stage, higher water-soluble carbohydrate (WSC) and water-insoluble carbohydrate (WISC) were contained in stem compared with other parts, showing that WISC of sheath and stem, unlike WSC, was significantly different among N levels. Starch of grain, WISC, was remarkedly increased from 3.0% at just after the flowering to 52.0% and 75.0% at 15 and 30 day after the flowering, respectively, showing that lower N application had faster accumulation of starch in rice grains. N would affect the contents of carbohydrates of each tissue, and starch accumulation in rice grains.

• 한국농공학회논문집
• /
• 제46권1호
• /
• pp.99-105
• /
• 2004

The present agricultural water quality standards are set by a policy goal. This is intended for water quality management of public water resources, but not for the use of water resources. These standards were not determined by considering the influence of water quality on the safety of agricultural produce and the growth, yield and quality of agricultural crops. Thus, this study was carried out to investigate the influence of irrigation water quality on the growth, yield, and grain quality of rice and acquire fundamental knowledges to set up irrigation water quality standards. The pot experiment was conducted with 4 treatments using irrigation waters with various total nitrogen concentrations (control, 1, 5, 10, 20mg/L) and replicated four times with randomized block design. The results of this study showed that plant height, number of tiller, plant dry weight, the uptake of N, P, and K, and rice protein contents tended to increase as the T-N concentration in irrigation water was increased. In addition, grain yield at T-N 20 mg/L was significantly higher than in the control, but the percentage of head rice was slightly lower due to the increase of green kernel and white belly/core kernel.

• 한국산림과학회지
• /
• 제85권2호
• /
• pp.271-279
• /
• 1996

이 연구는 비탈면 녹화용(綠化用) 자생목본(自生木本)과 초본종자(草本種子) 적정혼파비(適定混播比)를 결정하기 위해, 서울대학교 농업생명과학대학 실내온실에서 목본(木本) 초본종자(草本種子)의 파종실험(播種實驗)을 실시하였으며, 파종(播種)은 목본(木本)의 경우 초기발아기대본수 60립(粒)/$m^2$을 기준으로 초본종자(草本種子)와 혼합하여 복토량(覆土量), 시비처리(施肥處理), 파종량별(播種量別)로 실험하여 얻은 결과를 분석한 것이다. 1994년 6월 파종후(播種後) 목본(木本)과 초본(草本)의 개체수(個體數), 생중량(生重量), 수고(樹高)와 초고변화(草高變化), 분얼수(分蘖數)를 조사한 결과, 목본(木本)의 개체수(個體數)는 1995년에 싸리가 파종구(播種區)($m^2$)별(別)로 평균 1.14본(本), 족제비싸리 0.496본(本)이였으며, 조팝나무와 물오리나무는 파종 발아후 당해년도(1994)에 고사하였다. 초본(草本)의 경우는 1995년에 달맞이꽃이 5.06본(本), 솔새 1,072본(本), 개솔새는 0본(本)이였으며, 억새는 412.53본(本), 쑥 88.6본(本), 비수리 8.9본(本), 새 57.46본(本)으로 조사되었다. 지상부생장(地上部生長)에 있어서, 목본(木本)의 싸리와 족제비싸리는 급격한 지상부생장(地上部生長)과 생중량(生重量)의 증가를 보이고, 초본(草本)의 경우에는 파종 당해년도에 솔새, 개솔새, 억새, 달맞이꽃, 새 등은 생장(生長)이 빠르나 파종 이듬해에는 솔새와 억새가 지상부(地上部) 및 생중량(生重量)의 증가가 높았다. 파종량(播種量)에 따른 목본(木本)의 변화를 보면, 파종 당해년도에는 수종(樹種)간에 유의성(有意性)이 없었으나, 파종 이듬해에는 파종량(播種量)에 따라 유의(有意)하였고, 초본(草本)의 경우는 파종량(播種量)과 개체수(個體數)의 변화는 파종당해년도와 이듬해 모두 유의(有意)하였다. 분얼(分蘖)이 가장 우수한 것은 억새(21개)로 나타났으며, 다음은 솔새, 새 순으로 나타났다. 녹화용(綠化用) 자생목본종자(自生木本種子)와 초본종자(草本種子)의 혼파(混播)에서, 초본(草本)의 종자량(種子量)이 많을수록 목본(木本)의 개체수(個體數), 지상부(地上部) 생장량(生長量), 생중량(生重量), 초본분얼수(草本分蘖數) 등은 감소하였다. 따라서, 비탈면의 녹화식생(綠化植生)으로, 목본(木本)은 싸리와 족제비싸리, 초본(草本)으로는 분얼(分蘖)이 우수한 새류(類)를 이용하는 것이 효과적이라 분석되며, 목본(木本)의 성립(成立)을 위해서는 파종량(播種量)에 대한 연구가 더욱 수행되어야 할 것이다.