• The Korean Journal of Mycology
• /
• v.3 no.2
• /
• pp.7-12
• /
• 1975

Three species of Pythium previously not recorded in Korea were found during 1975. Pythium spinosum Sawada was isolated from diseased cabbage seedlings, P. myriotylum Dreschl. was isolated from kidney bean and P. butleri Subramanium from cucumber, spinach, red bean and radish. Pathogenicity of isolates of P. butleri and P. myriotylum was confirmed in pathogenicity tests but P. spinosum appeared to be non-pathogenic. Several isolates failed to sporulate satisfactorily on cornmeal agar and some produced degenerate oogonia after sub-culturing on this medium. Sunflower seed agar was found to be a suitable alternative medium. The validity of previous records of P. debaryanum Hess in Korea is discussed.

• The Korean Journal of Mycology
• /
• v.31 no.3
• /
• pp.141-147
• /
• 2003

The pileus of Pleurotus cystidiosus was attached at the side and was spatular-shape. It grew to the size of $7.6{\sim}9.8\;cm$ with dark brown color. The length of stem was $1.4{\sim}2.9\;cm$. The individual weight of fruiting-body was 25.4 g in average. This study was conducted to Investigate the physiological characteristics and to develop the artificial cultivation technique of P. cystidiosus. To find out the optimum condition of mycelial growth of P. cystidiosus, physiological conditions such as media, temperature, pH carbon sources and nitrogen sources were investigated. Various cultural media were used for the cultivation of P. cystidiosus and compost dextrose agar was favorable for mycelial growth. The optimal growing temperature and pH were in range of 25 to $30^{\circ}C$, pH $7{\sim}9$, respectively. When different carbon sources were compared, glucose was found to be best. However nitrogen sources were different with each strains. When different C/N ratio were compared, 20:1 of C/N ratio was found to be best.

• The Korean Journal of Mycology
• /
• v.31 no.3
• /
• pp.200-205
• /
• 2003

The study was carried out on the artificial cultivation of the abalone mushroom, Pleurotus cystidiosus O.K.Miller. The pine sawdust substrates with 20% rise bran were good for mycelial growth and high quantity of P. cystidiosus in the bottle cultivation. Moreover, the proper volume for bottle cultivation was 850 ml and the removal of spawn and surface layer of the medium before pin-heading was more efficient. The yields of P. cystidiosus were higher in sawdust substrates added calcium carbonate than those not added calcium carbonate. The volume of 3 kg polypropylene bag is good for yield and biological efficiency in bag cultivation of P. cystidiosus. Cotton wastes were proper substrates for bag cultivation. In the effect of different cultivation temperature, $28{\pm}2^{\circ}C$ cultivation temperature was good for for primordial formation after inoculation.

• Korean Journal of Agricultural Science
• /
• v.47 no.4
• /
• pp.753-767
• /
• 2020

The commercial value of strawberries is affected by various factors such as their shape, size and color. Among them, size determined by weight is one of the main factors determining the quality grade of strawberries. In this study, image technology was developed to predict the weight of strawberries using the shape characteristics of strawberry cultivars. For realtime weight measurements of strawberries in transport, an image measurement system was developed for weight prediction with a charge coupled device (CCD) color camera and a conveyor belt. A strawberry weight prediction algorithm was developed for three cultivars, Maehyang, Sulhyang, and Ssanta, using the number of pixels in the pulp portion that measured the strawberry weight. The discrimination accuracy (R2) of the weight prediction models of the Maeyang, Sulhyang and Santa cultivars was 0.9531, 0.951 and 0.9432, respectively. The discriminative accuracy (R2) and measurement error (RMSE) of the integrated weight prediction model of the three cultivars were 0.958 and 1.454 g, respectively. These results show that the 2D imaging technology considering the shape characteristics of strawberries has the potential to predict the weight of strawberries.

• Food Science and Industry
• /
• v.46 no.2
• /
• pp.33-47
• /
• 2013

• Proceedings of the Korean Society of Sericultural Science Conference
• /
• 2005.04a
• /
• pp.20-21
• /
• 2005

• Korean Journal of Plant Resources
• /
• v.29 no.6
• /
• pp.658-669
• /
• 2016

Rice blast, caused by a fungus Magnaporthe oryzae, is one of the most devastating diseases of rice worldwide. Analyzing the valuable genetic resources is important in making progress towards blast resistance. Molecular screening of major rice blast resistance (R) genes was determined in 2,509 accessions of rice germplasm from different geographic regions of Asia and Europe using PCR based markers which showed linkage to twelve major blast R genes, Pik-p, Pi39, Pit, Pik-m, Pi-d(t)2, Pii, Pib, Pik, Pita, Pita/Pita-2, Pi5, and Piz-t. Out of 2,509 accessions, only two accessions had maximum nine blast resistance genes followed by eighteen accessions each with eight R genes. The polygenic combination of three genes was possessed by maximum number of accessions (824), while among others 48 accessions possessed seven genes, 119 accessions had six genes, 267 accessions had five genes, 487 accessions had four genes, 646 accessions had two genes, and 98 accessions had single R gene. The Pik-p gene appeared to be omnipresent and was detected in all germplasm. Furthermore, principal component analysis (PCA) indicated that Pita, Pita/Pita-2, Pi-d(t)2, Pib and Pit were the major genes responsible for resistance in the germplasm. The present investigation revealed that a set of 68 elite germplasm accessions would have a competitive edge over the current resistance donors being utilized in the breeding programs. Overall, these results might be useful to identify and incorporate the resistance genes from germplasm into elite cultivars through marker assisted selection in rice breeding.

• Korean Journal of Agricultural Science
• /
• v.40 no.1
• /
• pp.53-59
• /
• 2013

Analysis of load data during field operations is highly important for optimum design of power drive lines for agricultural tractor. Objective of the paper was to analyze field load data using FFT to determine frequency and the energy levels of meaningful cyclic patterns. Rotary tillage, plowing, baling, and wrapping operations were selected as major field operations of agricultural tractor. An agricultural tractor with power measurement system was used. The tractor was equipped with strain-gauge sensors to measure torque of four driving axles and a PTO axle, speed sensors to measure rotational speed of the driving axles and an engine shaft, pressure sensors to measure pressure of hydraulic pumps, an I/O interface to acquire the sensor signals, and an embedded system to calculate power requirement. In rotary tillage, calculated frequency was decreased as travel speed increased. In baler operation, calculated frequency was increased as PTO speed was increased. The calculated peak frequency levels and expected levels were similar. Results of the study would provide information on power utilization patterns and on better design of power drive lines.

• Journal of Microbiology and Biotechnology
• /
• v.12 no.6
• /
• pp.998-1001
• /
• 2002

Potential antitumor activity of Lactobacillus plantarum cytoplasm was examined using F9 teratocarcinoma-bearing BALB/C mice. The cytoplasmic fraction of L. plantarum was separated by sonication followed by ultracentrifugation. The fraction at a dose of 100 or 200 mg/kg/day was orally administered for 7 consecutive days before or after tumor inoculation to 16 mice. As a control, heat-killed whole cell was used at a dose of 100 mg/kg/day. Upon oral administrations of both the cytoplasm and heat-killed whole cell, when performed after and before tumor inoculation, the survival of F9-bearing mice prolonged more effectively. Administration of the cytoplasm after tumor inoculation extended the average survival days by 30 and $40\%$ at daily dosages of 100 and 200 mg/kg/day, respectively. This result suggests that the cytoplasmic fraction of L. plantarum has strong antitumor activity against mouse F9 teratocarcinoma in vivo.

• Korean Journal of Organic Agriculture
• /
• v.19 no.spc
• /
• pp.291-294
• /
• 2011

We studies a model for management of pepper anthracnose based covering method and spraying system in field. 1. Among 82 organic fungicides, 42 materials showed most effective inhibition against mycelia growth of the Colletotrichum acutatum in vitro. 23 formulated biocontrol agents were chosen to control the disease from 42 biocontrol agents in greenhouse. In the end, five kinds (2 plant extracts, 2 biopesiticides, 1 Bordeaux mixture) were selected from 23 materials in the field. 2. The mulching materials of bed covering in fruit season were thin non-woven fabric sheet and black plastic. The use of a fabric sheet was reduced the spread of anthracnose as compared to the plastic covering. 3. The application with the chosen materials was reduced 34% of anthracnose for 7 times sprays to planting 70 days as compared to the untreated control. In yield, nonwoven fabric sheet with formulated biopesticides was increased 17% than black plastic. 4. This result indicated that the developed biocontrol strategy could be an effective and economic crop protection system in organic pepper cultivation field.