• Journal of Radiation Protection and Research
• /
• v.26 no.4
• /
• pp.409-415
• /
• 2001

To observe the stimulating effects of low dose gamma radiation on the germination and physiological activity of germinating seeds of old red pepper (Capsicum annuum L. cv Jokwang and cv. Hongkwang), seeds were irradiated at the dose of $2{\sim}50 Gy$. The germination rate of irradiation group was higher than that of the control. Especially it was highest at the early stage of induction. The germination rate at 7 days after sowing in Jokwang and Hongkwang cultivar was high as 74% and 11% at 4 Gy and 8 Gy irradiation group, respectively. The seedling height of Jokwang cultivar was noticeably high at 4 Gy irradiation group and that of Hongkwang cultivar at 8 Gy irradiation group. The protein contents of seedlings from seeds irradiated with low dose gamma radiation of Jokwang cultivar increased at the late stage of induction and that of Hongkwang cultivar at the early stage of induction. Catalase and peroxidase activities of seedlings from seeds irradiated with low dose gamma radiation of Jokwang cultivar increased at 4 Gy irradiation group and that of Hongkwang cultivar at 8 Gy irradiation group.

• Journal of Bio-Environment Control
• /
• v.18 no.1
• /
• pp.51-59
• /
• 2009

Bulb onion cultivation area has been restricted in southern part of Korea to avoid blotting and bulb division. The traditional culture method is transplanting bare-rooted plantlet into the field at the end of summer and harvesting at the beginning of next summer. The hot weather and weak plantlets occasionally causes unstable supply of onions in autumn. In order to enlarge cultivation area and to reduce culture period, long nursery system using plug tray and spring transplanting was tried. Forty cultivars collected from Korea and Japan were nursed using 200-plug tray and transplanted to the field in spring. Marketable yield was not related to the seedling size but lodging time. Cultivar of 'Hamasodachi' was lodged early and resulted low marketable yield. Cultivar of 'Cheonjudaego' was not lodged and yielded high but not in accordance with storability. Generally early lodged cultivars showed low storability. In order to avoid rainy harvesting season, cultivars requires excessive long time for lodging is not recommended for spring culture. Using plug nursery and spring transplanting, we successfully produced marketable onions in 3 months. But immediate using of the harvested onion is recommended. The storability of produced onions showed different result among cultivars, storage of spring onion was not recommended.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.55 no.2
• /
• pp.165-176
• /
• 2010

Soybean seeds contain many biologically active secondary metabolites, such as proteins, saponins, isoflavones, phytic acids, trypsin inhibitors and phytosterols. Among them, saponins in soybeans have attracted considerable interest because of their health benefits. Soyasaponin A and B are the most abundant types of saponins found in soybeans along with soyasapogenol (aglycone), which is a precursor of soyasaponin. The main purpose of this experiment was to determine the concentration of soyasapogenol in soybean seeds and sprouts as a function of seed size, usage, seed coat color and seed cotyledon color. The 79 Korean soybean varieties were cultivated at Yesan of Chungnam in 2006 for the analysis of soyasapogenol using HPLC with Evaporative Light Scattering Detection (ELSD). The total average concentration of soyasapogenol was $1313.52{\mu}g\;g^{-1}$ in soybean seeds and $1377.22{\mu}g\;g^{-1}$ in soybean sprouts. Soybean sprouts were about 5% higher than soybean seeds in average total soyasapogenol concentration. In the process of sprouting, the average soyasapogenol A content decreased by approximately 1.6%, but soyasapogenol B and total soyasapogenol increased by 8.31% and 4.88%, based on the content of soybean seeds. When classified according to the size of seeds, the total soyasapogenol concentration of soybean seeds were not significantly different (p<0.05) On average, small soybean seeds were increased by as much as $103.14{\mu}g\;g^{-1}$ in sprouting process. As a function of the use of the seeds, The total soyasapogenol in soybean seeds were significantly different (p<0.05). While, the soybean sprouts were not significant different (p<0.05). Altogether, sprout soybean seeds show the greatest change in content during the germination process. When seeds with different coat colors were compared, the total soyasapogenol concentration of soybean with yellow seed coats ($1357.30\mu g\;g^{1}$) was slightly higher than that of soybean with black ($1260.30{\mu}g\;g^{-1}$) or brown ($1263.62{\mu}g\;g^{-1}$) seed coats. For the color of the cotyledon, the total soyasapogenol concentration was significantly increased in green cotyledon during the germination and seedling process. The results of this study suggest the functional characteristics of soybeans through quantitative analysis of soyasapogenol. In addition, the concentration of soyasapogenol exhibited a change during the germination process, which was evaluated by the nutritional value of the soybean sprouts.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.6
• /
• pp.614-620
• /
• 2002

The sea bass, Lateoiabrax japonicus is a highly valued fish in aquaculture in South Korea. For establishment of seedling production of sea bass,1 japonicus, we examined change of gonadal development and plasma steroid levels of sea bass reared in indoor tank. Male matured unsimultaneously faster than females and spawning of females took place between the end of January and March. After the spawning period, and until the following January, all the females were in preyitello genesis and in some males, spermatogenetic activity restarted gradually. In October, under reducing photoperiod, cortical alveoli appeared in growing oocyte and the development of spermatogenesis greatly increased. Between October and february, vitellogenesis and spermatogenesis occurred respectively in female and male and gonadosomatic index increased from 4.31 to $24.07\%$ in female and upper 6o/o in male. Also, two sex hormones were analyzed during the course of a reproductive cycle in the sea bass: plasma levels of the gonadal steroid testosterone (T) and estradiol-l7$\beta$ (E_{2}). Variation of the plasma concentrations of T and E, appeared to depend on gonad stages. Plasma T and E, levels were high from November to January, suggesting that an sufficient gonadal stimulation by both hormones may undergoing a processes for the formation of sperm and oocyte.

• Korean Journal of Soil Science and Fertilizer
• /
• v.39 no.5
• /
• pp.298-302
• /
• 2006

This study was carried out to establish low-input fertilization and seeding technique using the simultaneous with seeding and fertilizer application machine and band spotty applicator which were manufactured for experiment during cultivation of mulching for peanut(Arachis hypogaea L.). The labor hour for seeding by simultaneous with seeding and fertilizing machine was appeared over 90% reduction effect compared with control plot($17.3hr\;10a^{-1}$). In band spotty fertilization plots, the emergence date was delayed about 4 days and the seedling stand rate was decreased 11~18% compared with control plot(man power). The content of total nitrogen of soil after experiment was increased while the contents of organic matter, available phosphate and exchangeable potassium were decreased than before experiment. The content of nitrogen forming nitrate was increased in band spotty fertilization(BSF) plots by increasing the amount of applied fertilizer from early growth stage till the middle growth stage. Growth rate was increased in band spotty fertilization plots and the absorbed amount of phosphate and potassium for peanut were increased in 70% band spotty fertilization plot compared with control plot. Yield of peanut was increased 70% in band spotty fertilization plot due to high pod kernel ratio and ripened pod rate compared with control plot($3,150kg\;ha^{-1}$). It was found that 70% band spotty fertilization was more effective as fertilization method to reduce both environmental pollution and chemical nitrogen fertilizer in plastic film mulching cultivation of peanut.

• Journal of Sericultural and Entomological Science
• /
• v.52 no.2
• /
• pp.147-154
• /
• 2014

We bred a mulberry cultivar named Palcheong, through local adaptability test, which is under registration as a new cultivar for fruit production. Local adaptability test had been carried out at four places (Suwon, Kongju, Wanju, and Jinju) for seven years from 2007. This is belonging to (Morus Lhou(Ser.) Koidz.) selected among mulberry genetic resources preserved in Suwon. Its sex expression was hermaphrodite, which can be used for the production of seedling for fruit production by artificial crossing as pollen parent Palchung showed lower yielding in fruit productivity by 16% compared to control cultivar 'Chungil (Morus alba L.)' for five years. Although Palchung was higher in sugar content of mulberry fruits, it was bigger than that of 'Chungil'. It is adaptable to every where except the places where cold damage and sclerotic disease happen frequently.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.36 no.1
• /
• pp.35-44
• /
• 2016

Seed viability is one of the most important parameters that is directly related with seed germination performance and seedling emergence. In this study, a hyperspectral imaging (HSI) system having a range of 1000-2500 nm was used to classify viable watermelon seeds from nonviable seeds. In order to obtain nonviable watermelon seeds, a total of 96 seeds were artificially aged by immersing the seeds in hot water ($25^{\circ}C$) for 15 days. Further, hyperspectral images for 192 seeds (96 normal and 96 aged) were acquired using the developed HSI system. A germination test was performed for all the 192 seeds in order to confirm their viability. Spectral data from the hyperspectral images of the seeds were extracted by selecting pixels from the region of interest. Each seed spectrum was averaged and preprocessed to develop a classification model of partial least square discriminant analysis (PLS-DA). The developed PLS-DA model showed a classification accuracy of 94.7% for the calibration set, and 84.2% for the validation set. The results demonstrate that the proposed technique can classify viable and nonviable watermelon seeds with a reasonable accuracy, and can be further converted into an online sorting system for rapid and nondestructive classification of watermelon seeds with regard to viability.

• Horticultural Science & Technology
• /
• v.18 no.1
• /
• pp.33-38
• /
• 2000

This study was conducted in an effort to meet the need for domestic production of hydroponic media and for medium development using recycled hydroponic rockwool slabs. Two experiments were conducted to evaluate the growth of plug seedlings of petunia 'Romeo' in various mixtures including particles of used rockwool slabs (rockwool particles) and wood chips. In the first experiment, seedlings were grown in plugs filled with mixtures of steam- sterilized rockwool particles and chestnut wood chips, which had been weathered for six months and screened through either 2.8 mm or 5.6 mm sieve, at the mixing ratio of 100:0, 75:25, 50:50, 25:75, or 0:100 (v/v). In the second experiment, seedlings were grown in plugs filled with twenty different mixtures of steam-sterilized particles of used hydroponic rockwool slabs with 4 mm chestnut or pine wood chips, coir, peatmoss, or perlite. In the first experiment seedling growth was not affected by particle size of chestnut wood chips, was superior in the control (commercial plug medium) and in 100% rockwool particles, but was suppressed as mixing ratio of chestnut wood chips increased. In the second experiment, leaf length, and shoot fresh and dry weights were the greatest in rockwool particles+peatmoss+coir treatment, followed by rockwool particles+peatmoss treatment. Leaf length was suppressed as ratio of wood chips increased, especially of chestnut wood chips. Root development was the greatest in rockwool particles+peatmoss+perlite treatment, followed by the control, and rockwool particles+peatmoss+coir treatment. The growth was suppressed as the mixing ratio of rockwool particles, peatmoss, or coir decreased.

• Journal of Bio-Environment Control
• /
• v.13 no.1
• /
• pp.61-66
• /
• 2004

To investigate the effect of charcoal on the physico-chemical characteristics in the growing media and the growth of oriental melon, six treatment, 0%, 10%, 20%, 30%, 40%, and 50% charcoal, were added into the growing media, Baroker. The value of pH in the charcoal contained growing media (CGM) was recorded higher and further increased by raising the charcoal ratio and by growing period. In 20% CGM, the range of pH was adequate to grow crop as 5.2${\sim}$5.8. Contents of Ca and K in CGM increased by raising the ratio of charcoal, while contents of Mg and Na decreased. The growth of oriental melon seedlings in 20% and 30% CGM was better than in other treatments, in terms of fresh and dry weight of shoot, plant height, leaf area, lear width and relative growth rate. Both the physico-chemical properties of growing media and the growth of oriental melon seedlings were changed by the addition of charcoal. These results suggest that charcoal can be used as mixing material with other potting media for producing the seedling of good quality.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.5
• /
• pp.654-658
• /
• 1999

To investigate an efficient microalgal feed for lariat culture of the Pacific oyster Crassostrea gigas, we prepared three types of Isochrysis aff, galbana (T-iso) : 1) freshly Harvested feed, 2) concentrated feed and 3) freeze-dried feed. The chemical compositions and fatty acid content of these feeds were evaluated and survival rate and lipid content of oyster larvae fed by these feeds were also determined. There was no significant difference in all types of feed in the gross biochemical compositions, In the fatty acid composition, the freeze-dried feed showed a significant increase in the level of polyunsaturated fatty acid (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) than freshly Harvested feed, especially EPA was 7.35-fold higher than freshly Harvested feed. The survival rate of the oyster larvae was the highest when the larvae were fed with a diet of $10\%$ freeze-dried and $90\%$ concentrated feed; it was 2.1-fold higher than that fed with freshly Harvested food alone. Thereafter, the survival rate decreased with the increased substitutions of freeze-dried food, finally equalling that fed $100\%$ freshly harvested feed at the $30\%$ substitution. Larval lipid content of the oyster was also the highest when the larvae were fed with a diet of $10\%$ freeze-dried and $90\%$ concentrated feed. This increase was by 1.6-fold ver that fed $100\%$ freshly Harvested cells. Thus feed produced during slack times, on a seedling aquaculture farm, and preparedas a freeze-dried diet can be used, mixed with concentrated feed, to supply diets more efficiently and to improve the larvae survival rate of Pacific oyster.