• Journal of People, Plants, and Environment
• /
• v.23 no.6
• /
• pp.655-665
• /
• 2020

Background and objective: This study was conducted to compare the cultivation environment, growth of cut flowers, and management performance of conventional farms and smart farms growing the standard cut chrysanthemum, 'Jinba'. Methods: Conventional and smart farms were selected, and facility information, cultivation environment, cut flower growth, and management performance were investigated. Results: The conventional and smart farms were located in Muan, Jeollanam-do, and conventional farming involved cultivating with soil culture in a plastic greenhouse, while the smart farm was cultivating with hydroponics in a plastic greenhouse. The conventional farm did not have sensors for environmental measurement such as light intensity and temperature and pH and EC sensors for fertigation, and all systems, including roof window, side window, thermal screen, and shading curtain, were operated manually. On the other hand, the smart farm was equipped with sensors for measuring the environment and nutrient solution, and was automatically controlled. The day and night mean temperatures, relative humidity, and solar radiation in the facilities of the conventional and the smart farm were managed similarly. But in the floral differentiation stage, the floral differentiation was delayed, as the night temperature of conventional farm was managed as low as 17.7℃ which was lower than smart farm. Accordingly, the harvest of cut flowers by the conventional farm was delayed to 35 days later than that of the smart farm. Also, soil moisture and EC of the conventional farm were unnecessarily kept higher than those of the smart farm in the early growth stage, and then were maintained relatively low during the period after floral differentiation, when a lot of water and nutrients were required. Therefore, growth of cut flower, cut flower length, number of leaves, flower diameter, and weight were poorer in the conventional farm than in the smart farm. In terms of management performance, yield and sales price were 10% and 38% higher for the smart farm than for the conventional farm, respectively. Also, the net income was 2,298 thousand won more for the smart farm than for the conventional farm. Conclusion: It was suggested that the improved growth of cut flowers and high management performance of the smart farm were due to precise environment management for growth by the automatic control and sensor.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.24 no.4
• /
• pp.53-61
• /
• 2022

Growing agricultural products in greenhouses controlled by creating suitable climatic conditions and root zone of crop has been an important research and application subject. Appropriate environmental conditions in greenhouse are necessary for optimum plant growth improved crop yields. This study aimed to establish web-based remote monitoring system which monitors crops growth environment and status of crop on a real-time basis by applying to greenhouses IT technology connecting greenhouse equipment such as temperature sensors, soil sensors, crop sensors and camera. The measuring items were air temperature, relative humidity, solar radiation, CO₂ concentration, EC and pH of nutrient solution, medium temperature, EC of medium, water content of medium, leaf temperature, sap flow, stem diameter, fruit diameter, etc. The developed greenhouse monitoring system was composed of the network system, the data collecting device with sensors, and cameras. Remote monitoring system was implemented in a server/client environment. Information on greenhouse environment and crops is stored in a database. Items on growth and environment is extracted from stored information, could be compared and analyzed. So, A integrated monitoring system for smart greenhouse would be use in application practice and understanding the environment and crop growth for smart greenhouse management. sap flow, stem diameter and pant-water relations

• Journal of Bio-Environment Control
• /
• v.32 no.3
• /
• pp.234-241
• /
• 2023

This study was conducted to investigate the growth of lettuce (Lactuca sativa L.) and Korean mint (Agastache rugosa Kuntze) with microbubble in a closed-type plant production system (CPPS) with a deep flow technique (DFT). Lettuce and Korean mint were grown in CPPS for 23 days. Microbubble was treated for 5 minutes daily at 9:00, 13:00, and 17:00 for 16 days. The leaf length, leaf width, leaf area, and fresh and dry weights of lettuce and Korean mint were significantly lower in microbubble than in the control. The total root length, root surface area, and the number of root tips of lettuce and Korean mint were significantly lower in the microbubble than in the control. In the case of average root diameter, there was no difference between the treatments of lettuce. However, Korean mint significantly increased in thickness in the microbubble treatment, indicating variations among the different crops. The results of the research indicated that microbubble treatment in the DFT inhibited plant growth by inducing abiotic stress in lettuce and Korean mint.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.4
• /
• pp.282-287
• /
• 2022

BACKGROUND: Green algae (Chlorella spp.) has been widely used as a biofertilizer to improve the crop yield and quality. However, available information is not enough to verify the mechanism of green algae's beneficial impact on strawberry. This study was conducted to investigate the effect of Chlorella fusca CHK005 application on the growth and nutrient status of strawberry plant and fruit characteristics. METHODS AND RESULTS: A total of 800 seedlings of strawberry variety 'Kuemsil' were planted. Once a week, C. fusca culture solution (1.0 × 10⁷ cells mL^-1) was applied into soil via irrigation in four different concentrations: no application (control), 1/1000 times (× 0.5), 1/500 times (× 1), and 1/250 times (× 2). Result showed that growth of strawberry plant was enhanced by Chlorella application and the highest impact on fresh weight (FW) and chlorophyll content of the plants were observed in × 2 treatment, followed by × 1, × 0.5, and control treatments. The phosphorus (P) concentration in the plant was significantly higher in × 1 and × 2 treatments compared to control. In case of fruit quality, sugar content (°Brix), hardness, and FW were lowest in control, but these values increased as application levels of Chlorella were higher. Also, P and K contents in the fruits increased with increasing the application levels and significant correlation between P content and oBrix in the fruits was found. CONCLUSION(S): Overall, Chlorella application seemed to improve plant growth and fruit quality by increasing the utilization efficiency of P and K in strawberries.

• Journal of Bio-Environment Control
• /
• v.22 no.4
• /
• pp.408-412
• /
• 2013

This study was carried out to investigate damp injury caused by tomato coir bag culture and prevent that. The tomato variety was used 'Minichal', and tomatoes were grown in greenhouse. The nutrient solution based on Yamazaki Tomato Standard Solution was irrigated from one hour after sunrise to two hour before sunset. The slits for darainage were made in three types; I, L, and bottom slit type. The coir bag of I and L type had six slits of 15cm length, that of bottom slit type had three slits of 15 cm length. The weight of coir bag in 24 hours after saturation was 14.2 kg in I type, 13.8 kg in L type, and 12.8 kg in bottom slit type, but there was not significant difference. The weight of coir bag after one day irrigation was 14.5 kg, 14.2 kg, and 13.3 kg at L, I, and bottm slit type, respectively. This means that the moisture content of coir bag during cultivation was lowest in bottom slit type. The number of adventitious root on stem was 160, 170, and 53 at I, L, and bottom slit type, respectively. The dry weight of root and root length were highest at bottom slit type, compared to other treatment. The marketable yield was highest 26.5 kg/20 plant in bottom slit type. For increasing yield and preventing damp injury, bottom slit type was most effective at U type bed coir bag culture.

• Horticultural Science & Technology
• /
• v.34 no.2
• /
• pp.228-235
• /
• 2016

This study was conducted to determine the yield of cherry tomato (Solanum lycopersicum Mill.) grown at three planting times during the uncultivated period of strawberry. Cherry tomato was planted under condition filled with strawberry dedicated culture medium on a two-story bed with April 20, April 30, and May 10 at 2015. Fruit harvest was completed on July 31. The supply concentration of nutrient solution at the time of transplanting was started as EC $1.2dS{\cdot}m^{-1}$ and it was gradually increased to EC $2.5dS{\cdot}m^{-1}$ after blooming of the first flower cluster. Netherlands PBG solution was supplied for one minute six times per day. The heights of cherry tomato plants planted at earlier were significantly greater than those of tomato plants planted later. The heights of cherry tomato plants grown at the bottom of the bed were greater than those grown in the upper bed. The yield of cherry tomatoes planted on April 20 at the bottom of the bed was greatest with an average of 2,954 g of tomatoes per plant. There were no significant differences in the average weight and sugar content of fruit according to planting times and bed position. The yield of cherry tomato plants planted on April 20 was 18% and 34% higher than that of plants planted on April 30 and May 10. We confirmed to increase the yield of the cherry tomato when early plants planted on two-story bed. These results indicate that farmers can choose the best period of producing cherry tomato during the un-cultivated period of strawberry under two-story bed conditions.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.6
• /
• pp.885-891
• /
• 2011

We conducted this study to determine the optimum dose of gamma irradiation needed for the sterilization of milk porridge for patients. Milk porridge, known as Tarakjuk, was irradiated with gamma ray at doses of 0, 1, 3, 5, 7, or 10 kGy. The microbial contamination, $D_{10}$ values of isolated microbe spores, color, and viscosity were measured during storage at $35^{\circ}C$. The initial count of total aerobic bacteria was 2.60 log CFU/g in the non-irradiated milk porridge, but coliforms, spore-forming bacteria, yeast, and molds were not detected. The total counts of aerobic and spore-forming bacteria in the non-irradiated and 1 kGy irradiated milk porridge increased with storage period. These microbes were not detected in the milk porridge irradiated with 10 kGy. The $D_{10}$ values of isolated spores from milk porridge were 2.71 kGy (in milk porridge) and 2.21 kGy (in saline solution). All CIE color increased with gamma irradiation, but the sensory value of color did not significantly change. The viscosity of the milk porridge decreased with gamma irradiation and storage period, and the decrease in viscosity with storage period became smaller as the radiation doses increased. Sensory evaluation scores of the milk porridge were above normal (4.0) when irradiated with less than 5 kGy. These results indicate that gamma irradiation could be beneficial for preparing food with higher nutrient density and lower viscosity, especially for gastric tube-fed patients.

• Korean Journal of Soil Science and Fertilizer
• /
• v.10 no.3
• /
• pp.153-170
• /
• 1977

Considering the ways for the possible improvement of soil test for upland crops, various methods for the evaluation of K supplying power and testing of available soil K were reviewed in terms of theoretical principles and practical usefulness of the each method. The review was also made on the characteristics of upland crops in K requirement and on the chemical properties of major korean upland and lowland rice soils in terms of K availability. Following is the few remarks drawn from the review. 1. Quite large number of methods have been known for the evaluation of K supplying power and testing for available soil K. In nature, they can be divided into two categories; capacity-based methods and intensity-based methcds. The capacity-based methods usually measure the exchangeable and some portion of nonexchangeable K, while the intensity-based methods suggest to consider the ractivity ratios of major cations in soil solution and the energy requirement for the replacement of exchangeable soil K into soil solution. 2. As methodology for extraction of interested part of soil K, chemical extraction, electrodialysis and ion exchange methods have been known. Among these, chemical extract ion is favorable because of its simplicity. However, recently suggested Electro-Ultra-Filtration method seems to merit further study for wider use for not only K but also other nutrient availability of soils. 3. The intensity-based methods, although they are more theoretical, because of their complexity, in methods may not be adapted for practical soil tests. 4. The exchangeable K which is rather simple to measure and which well reflects the status of K reserve as nonexchangeable and is immediate pool of water soluble K may be good, if not best, criterion of soil K availability to plant in common soil testing. 5. Because there are evidences that the abundance of available K alone may not be good inclication for availability of K to plant, it is recommendable to interprete the exchangeable K data as percent saturation of exchangeable K to total C. E. C. of soil for the recommend ation of K fertilizer based on soil tests. 6. Some pot and field trial results showed the trends that percent potassium saturation to total C. E. C. better serve as the parameter for K fertilizer recommendation.

• Korean Journal of Soil Science and Fertilizer
• /
• v.37 no.4
• /
• pp.220-227
• /
• 2004

Phosphorus desorption study is essential to understanding P behavior in agricultural and environmental soils because phosphorus is considered as two different aspects, a plant nutrient versus an environmental contaminant. This study was conducted to determine soil P buffering power related to P desorption quantity intensity (Q/I) parameters, $Q_{max}$(an index of P release capacity) and $l_0$(an index of the intensity factor), and to investigate the characteristics of relationship between the P desorption Q/I parameters and the soil properties. Soil samples were prepared with treatments of 0 and $100mg\;P\;kg^{-1}$ applied as $KH_2PO_4$ solution. The P desorption Q/I curves were obtained by a procedure using anion exchange resin beads and described by an empirical equation ($Q=aI^{-1}+bln(I+1)+c$). The P desorption Q/I curves for the high available P (${\g}20mg\;kg^{-1}$ of Olsen P) soils were characteristic concave trends with or without soil P enrichment, whereas for the low available P (${\lt}20mg\;kg^{-1}$ of Olsen P) soils, the anticipated Q/I concave curves could not be obtained without a proper amount of P addition. When the soils were enriched in phosphates, the values of desorbed solid phase labile P and solution P, such as $Q_{max}$ and $I_0$ respectively, were increased, but the ratio of $Q_{max}$ versus $I_0$ was decreased. Thus, the slope of desorption Q/I curve represented as phosphorus buffering power, $|BP_0|$, is decreased. The $|BP_0|$ values of the high available P soils ranged between 48 and $61L\;kg^{-1}$ in the P untreated samples and between 18 and $44L\;kg^{-1}$ in the P enriched samples. Overall $|BP_0|$ values of both low and high available P soils treated with $l00mg\;P\;kg^{-1}$ ranged between 14 and $79L\;kg^{-1}$. The $Q_{max}$, values ranged between 71.4 and $173.1mg\;P\;kg^{-1}$, and the lo values ranged between 0.98 and $3.82mg\;P\;L^{-1}$ in the P enriched soils. The $Q_{max}$ and $I_0$ values that control the P buffering power may be not specifically related to a specific soil property, but those values were complicatedly related to soil pH, clay content, soil organic matter content, and lime. Also, phosphorus release activity, however, markedly depended on the desorbability of the applied P as well as the native labile P.

• Journal of Bio-Environment Control
• /
• v.26 no.2
• /
• pp.115-122
• /
• 2017

Objective of this research was to investigate the influence of lowered substrate pH on the reduction of bicarbonate injury in the vegetative growth of 'Ssanta' strawberry. The acid substrate was formulated by mixing sphagnum peat moss with pine bark (5:5, v/v) and the pH, EC, and CEC of the substrate were 4.07, $0.46dS{\cdot}m^{-1}$, and $91.3cmol^+{\cdot}kg^{-1}$, respectively. To adjust the pH of acid substrate, various amount of dolomitic lime [$CaMg(CO_3)_2$] were incorporated with the rate of 0 (untreated), 1, 2, 3, and $4g{\cdot}L^{-1}$. Then, mother plants were transplanted and grown with fertilizer solution containing $240mg{\cdot}L^{-1}$ of the $HCO_3{^-}$ and equal concentrations of essential nutrients to Hoagland solution. In growth of 'Ssanta' strawberry, fresh weight of mother plants were the highest in the treatment of $2g{\cdot}L^{-1}$ dolomitic lime such as 102.1 g followed by 94.7 g in $1g{\cdot}L^{-1}$, 91.2 g in $3g{\cdot}L^{-1}$, 75.7 g in $0g{\cdot}L^{-1}$ and 72.3 g in $4g{\cdot}L^{-1}$ treatments. The dry weight showed a similar tendency to fresh weight. At 140 days after transplanting, 5.8, 9.8, 11.8, 8.8, and 5.0 daughter plants were derived from each of the mother plants in the treatments of 0, 1, 2, 3, and $4g{\cdot}L^{-1}$ dolomitic lime, respectively. The highest occurrence of daughter plants were observed in the treatments $2g{\cdot}L^{-1}$ dolomitic lime. The substrate pH and bicarbonate concentration of 'Ssanta' strawberry seedlings in the 1 and $2g{\cdot}L^{-1}$ dolomitic lime treatments were maintained at a proper range such as 5.6 to 6.2. The micro-nutrient contents of above ground tissue in mother plants were the highest in $2g{\cdot}L^{-1}$ and the lowest in $4g{\cdot}L^{-1}$ dolomitic lime treatment. The above results indicate that incorporation rate of dolomitic lime in acid substrate with the pH of around 4 is $2g{\cdot}L^{-1}$ to raise the 'Ssanta' strawberry in propagation.