• 농업과학연구
• /
• 제45권4호
• /
• pp.601-614
• /
• 2018

Chitosan with a natural antimicrobial property has been introduced to protect horticultural crops from diseases as an environmentally friendly method. The purpose of this study was to investigate the effects of the pre-harvest application of chitosan on growth and quality during the late stage of fruit development and on the simulated marketing of the peach fruit (Prunus persica L.). The application of chitosan with calcium chloride ($100mg{\cdot}L^{-1}$) three times at one week intervals 4 weeks before the harvest significantly increased the fruit weight, changed the fruit shape, and reduced the fruit length/diameter ratio giving the peach fruits a round oblate shape. The calcium treatment contributed to enhancing or maintaining the storage potential by increasing the flesh firmness. However, at higher concentrations of $CaCl_2$, i.e., > $600mg{\cdot}L^{-1}$, the positive effects of the chitosan application were offset, and fruit growth was not affected by calcium alone. The application of the chitosan/calcium mixture delayed fruit softening; however, this effect was shortened when the storage temperature was $20^{\circ}C$ rather than $15^{\circ}C$. The internal quality of the fruit was profoundly affected by the concentration of calcium added to the chitosan, and delayed fruit maturation was observed at a higher concentration of calcium. The pre-harvest application of chitosan with calcium contributes to the enhancement of food safety by inhibiting the occurrence of diseases during postharvest handling. Considering the above results, chitosan has the potential to improve both the yield of peach fruits and their storability. Because chitosan can enhance the freshness and shelf-life of fresh produce, it is necessary to examine its effects on other horticultural crops.

• 한국식품저장유통학회지
• /
• 제11권4호
• /
• pp.491-495
• /
• 2004

천연 저 칼로리 감미료로써 stevia의 소비가 증가하고 있는 시점에서 재배 및 기능성 식품소재로 이용하기 위하여 수확시기별 특성을 조사한 결과는 다음과 같다. 가용성 고형분 함량과 추출수율은 성장 기간이 길어질수록 증가하였고, pH는 감소하는 경향을 보였다. 색도와 투과율은 큰 변화가 없었으나, 성장 시기가 길어질수록 L, a, b값은 유사한 감소 경향을 나타내었고, 갈색도는 증가하였다. 성장기간 중 stevioside와 rebaudioside A의 비율은 stevioside는 $68.97\%$에서 $61.09\%$까지 감소하고, rebaudioside A는 $20.83\%$에서 $27.52\%$까지 증가하였다. Stevia 잎의 감미성분함량은 성장함에 따라 일정한 수준으로 증가하여 최고치는 8월말이며 함량은 $12.80\%$였고, 9월말에는 함량이 $12.10\%$로 감소하는 경향을 보였다. 최고 감미도는 25 - 30배였으며 감미질은 5월말에 채취한 시료가 가장 우수하였다.

• The Plant Pathology Journal
• /
• 제39권3호
• /
• pp.265-274
• /
• 2023

Citrus black rot is a serious disease of citrus plants caused by Alternaria citri. The current study aimed to synthesize zinc oxide nanoparticles (ZnO-NPs) by chemically or green method and investigate their antifungal activity against A. citri. The sizes of synthesized as measured by transmission electron microscope of ZnO-NPs were 88 and 65 nm for chemical and green methods, respectively. The studied prepared ZnO-NPs were applied, in vitro and in situ, at different concentrations (500, 1,000, and 2,000 ㎍/ml) in post-harvest treatment on navel orange fruits to verify the possible control effect against A. citri. Results of in vitro assay demonstrated that, at concentration 2,000 ㎍/ml, the green ZnO-NPs was able to inhibit about 61% of the fungal growth followed by 52% of chemical ZnO-NPs. In addition, scanning electron microscopy of A. citri treated in vitro with green ZnO-NPs showed swelling and deformation of conidia. Results showed also that, using a chemically and green ZnO-NPs at 2,000 ㎍/ml in situ in post-harvest treatment of orange, artificially-infected with A. citri, has reduced the disease severity to 6.92% and 9.23%, respectively, compared to 23.84% of positive control (non-treated fruits) after 20 days of storage. The out findings of this study may contribute to the development of a natural, effective, and eco-friendly strategy for eradicating harmful phytopathogenic fungi.

• 한국환경농학회지
• /
• 제42권4호
• /
• pp.279-285
• /
• 2023

The demand for the fresh leaf of hooker chive, which is mainly used as functional roots and contains dietary sulfur or saponin, is increasing, but the leaves are only harvested 3-4 times per year under conventional field conditions. A plant factory system with different light qualities or intensities was applied for year-round production of the fresh leaves. Hooker chive (Allium hookeri) roots were hydroponically cultured under the plant factory with a mixture of blue plus red LEDs (Light-Emitting Diodes) and fluorescent lights for 50 weeks. Maximum leaf growth was attained with the 1.5 dS/m EC in the culture medium under the plant factory. The average leaf and shoot numbers of hooker chive grown hydroponically under a mixture of 200 µmol/m²/s LEDs increased by 147% and 140%, respectively compared to those under 100 µmol/m²/s LEDs at the 10th harvest. The leaf length of hooker chive grown under the LEDs treatment with the lowest light intensity significantly increased by 27% compared with the natural light treatment at the 10th harvest. However, there was no significant difference in leaf pigmentation between natural and 200 µmol/m²/s LEDs treatments. Plant factory with the mixture LEDs of blue and red lights can be applied for year-round production of hooker chive fresh leaves to ensure a stable supply of leafy vegetable throughout the year.

• Journal of Biosystems Engineering
• /
• 제37권1호
• /
• pp.65-74
• /
• 2012

Purpose: An autonomous robot was developed for harvesting strawberries cultivated in bench-type systems. Methods: The harvest robot consisted of four main components: an autonomous vehicle, a manipulator with four degrees of freedom (DOF), an end effector with two DOFs, and a color computer vision system. Strawberry detection was performed based on 3D image and distance information obtained from a stereo CCD color camera and a laser device, respectively. Results: In this work, a Cartesian type manipulator system was designed, including an intermediate revolute axis and a double driven arm-based joint axis, so that it could generate collision-free motions during harvesting. A DC servomotor-driven end-effector, consisting of a gripper and a cutter, was designed for gripping and cutting the strawberry stem without damaging the strawberry itself. Real-time position tracking algorithms were developed to detect, recognize, trace, and approach strawberries under natural light conditions. Conclusion: The developed robot system could harvest a strawberry within 7 seconds without damage.

• 농촌계획
• /
• 제17권2호
• /
• pp.1-11
• /
• 2011

This research selected The Old Rectory, Sissinghurst and East Lambrook Manor as a case study location that is meaningful to discuss potager garden, herb garden and harvest garden, which is a topic of productive garden. This research focuses on the growth potential of Korea's rural house into a garden that embellishes decoration and appreciation. The application method through the interpretation of the case study location will be, first, organizing the shape of the flower bed and then adding additional materials along with the main materials. Second, it can increase the appreciation of productive garden through layering method and making it abundant. Third, it can be utilized well by pursuing artistic feature by combing unique color and texture of edible plants. Lastly, for the weakness of flat structure by short edible plants, vertical structure shall be utilized to provide decoration and frame. Also, by using natural materials, the ambiance of the garden can be presented.

• Journal of Plant Biotechnology
• /
• 제45권1호
• /
• pp.36-44
• /
• 2018

In this study, we evaluated the effect of different concentrations of chitosan and chitosan nanoparticles as edible coating in extending shelf life and maintaining the quality of banana fruits (Musa acuminata AAA group). The fruit treated with 1.15% chitosan, 1.25% chitosan and chitosan nanoparticles then store at ambient temperature ($25{\pm}1^{\circ}C$). The shelf-life of banana, starch content, weight loss, pulp to peel ratio, total soluble solid, surface morpholgy of banana peel and sensory evaluation were analysed. Molecular analysis on the effect of chitosan was also conducted. Results showed that the application of chitosan nanoparticles and chitosan could extend shelf-life and maintain quality of banana fruits.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2006년도 춘계학술대회
• /
• pp.593-596
• /
• 2006

This paper introduces various natural energy systems installed at the Eco-Science Center in Geumsan near Taejon. The center, especially, features different solar energy systems to harvest the solar energy to its full extent. Such passive schemes as direct gain and at lacked sun space are applied along with active solar ingredients using flat plate and double skin solar collectors. Space and water heating depends very little on the conventional means. Also a number of photovoltaic modules deployed within its premise supplies power to drive a water pump for the biotop. Combined with other natural energy utilizing systems, the solar energy systems make an exemplary model of a self sustainable public facility which is the first of its kind in Korea.

• Fisheries and Aquatic Sciences
• /
• 제25권8호
• /
• pp.409-416
• /
• 2022

This study aims to know the effect of water-extracted horseradish Moringa oleifera leaf and KW21 fertilizer combination application on the density of Nannochloropsis sp. It was conducted in the Natural Food Laboratory of State Polytechnique, Tual. The experiment used complete randomized design with 5 treatments and 3 replications: A (25% horseradish leaf extract + 75% KW21), B (50% horseradish leaf extract + 50% KW21), C (75% horseradish leaf extract + 25% KW21), D (positive control of 100% KW21), and E (negative control of 100% horseradish leaf extract). Results showed that Treatment C yielded the best result, both the highest density of Nannochloropsis sp. and suitable harvest time.

• 농약과학회지
• /
• 제8권3호
• /
• pp.184-188
• /
• 2004

살충제 thiodicarb의 단감 중 안전사용기준 설정과 안전성을 평가를 위하여 처리구별 단감 중 thiodicarb의 잔류량을 GLC/NPD로 분석한 결과, thiodicarb의 가수분해 산물인 methomyl oxime의 최소검출량은 0.2 ng이었으며, thiodicarb의 검출한계는 0.05 ppm 이었다. Thiodicarb의 평균 회수율은 0.5 ppm과 2.5 ppm 수준에서 각각 $93.9{\pm}3.9%$와 $92.8{\pm}2.0%$이었다. 각 처리별 평균 잔류량은 수확전 2회 살포시 $1.50{\pm}0.04$ ppm, 수확전 3회 살포시 $1.86{\pm}0.04$ ppm, 수확전 4회 살포시 $2.11{\pm}0.12$ ppm으로 처리구 모두 thiodicarb의 국내 잠정 잔류허용량(maximum residue limit)인 5 mg/kg 미만이었으며, 단감의 감꼭지나방 방제를 위하여 thiodicarb 40% 수화제를 수확 14일전 4회 살포시 안전성에는 문제가 없을 것으로 판단되었다.