• Journal of the Korea Organic Resources Recycling Association
• /
• v.10 no.3
• /
• pp.85-91
• /
• 2002

To investigate the agricultural material application possibility of the compost made by the fermenting tank. We evaluate the stability fertility of the compost In evaluation of the stability of the compost, In germination index of test, germination test of lettuce of little resistibility not germinated wholly, in the radish of resistibility, both Shinco and TM-101 is showed 61%, 55% of germination rate, length of root not showed wholly. In stability fertility of the compost, early growth of radish in a little treatment applied was superior to other treatments except for TM-101 treatment, but the latter growth of those was showed opposite result. In evaluation of the fertility of compost, Primary growth of lettuce was superior in treatment applied 1.5t/10a, the latter growth of those was superior in treatment applied 3t/10a.

• Korean Journal of Weed Science
• /
• v.7 no.2
• /
• pp.144-155
• /
• 1987

Water extracts of polygonum hydropiper and Polygonum aviculare completely inhibited the germination of lettuce seeds. Methanol extracts from these two species also inhibited the seed germination of lettuce (Lactuca sativa) and Oenothera odorata. Fifteen phenolic acids in total were identified by GLC from P. hydropiper and eighteen from P. aviculare. The most common phenolic acids identified from P. hydropiper were sinapic, salicylic+vanillic and ferulic acid presented in all the fractions. In addition, salicylic+vanillic, tannic+gallic, sinapic, ferulic and p-coumaric acid seemed to be important phenolic compounds in terms of quantity. However, salicylic+vanillic acids were the unique phenolic acids occurred in all the fractions of P. aviculare. The others such as tannic+gallic, sinapic, ferulic, p-coumaric acid, p-cresol and catechol present in large amount appeared also the important phenolic substances influencing allelopathic effects of P. aviculare. Linolenic acid and oxalic acid were the major fatty and organic acids in both plant species, presented in 2.38mg/g and 20.588mg/g in P. hydropiper, 3.70mg/g and 14.288mg/g in P. aviculare, respectively, which seem to be exhibiting allelopathic effects of these plants. Total alkaloids were presented in low amount such as 0.20% in P. hydropiper arid 0.22% in P. aviculare which may not be important elements. Pet. ether extracts were 2.42% in P. hydropiper and 1.65% in P. aviculare, which exhibit another potential for allelopathic effects that need further investigation. Various authentic phenolic compounds at different concentrations inhibited the germination of lettuce seed, indicating that the phenolic substances identified here may be directly related to biologically active substance.

• Korean Journal of Organic Agriculture
• /
• v.25 no.2
• /
• pp.345-355
• /
• 2017

This study was conducted to evaluate rice seed disinfection efficacy of loess-sulfur for the suppression of Bakanae disease caused by Fusarium fujikuroi. Rice seeds were treated at different concentrations of loess-sulfur, soaking time and temperature, and combination of hot-water treatment. Rice cultivar, Shindongjin harvested from Bakanae disease-infested area in 2015, was used. Loess-sulfur was treated as follows; concentration of undiluted solution, 2%, 1% and 0.5%; soaking time of 24 and 48 hours; treatment temperature of $20^{\circ}C$ and $30^{\circ}C$; hot water treatment or not. Optimal conditions of rice seed disinfection were selected soaking time of 48 hours and the suspension of 0.5% and 1% loess-sulfur by investigating seed germination and isolation frequency of Fusarium spp. on Komada agar medium in vitro, and were established 3 disinfection conditions as hot water ($60^{\circ}C$, 10 min.) + 1% loess-sulfur ($20^{\circ}C$, 48 hours), 1% loess-sulfur only ($30^{\circ}C$, 48 hours) and 1% loess-sulfur only ($20^{\circ}C$, 48 hours) through additional test in greenhouse. Above 3 conditions were verified by rice seedling box and paddy field test in the way of investigating Bakanae diseased plants (%) and healthy plants (%). Consequently, most effective rice seed disinfection conditions on Bakanae disease were combination of hot water and 1% loess-sulfur and loess-sulfur only at $30^{\circ}C$. Furthermore, treatments with these conditions showed control value of 100% were maintained from seedling to the heading stage in the field. However, treatment of 1% loess-sulfur only at $20^{\circ}C$ showed low control value of 78.2% in paddy field. Hot water only treatment turned out to be an effective disinfection method when conducted thoroughly with $60^{\circ}C$, 10 min. However, it was thought additional soaking process with loess-sulfur after hot water treatment served more high control effect against Bakanae disease when rice seeds were disinfected on a large scale. This results expected rice seed disinfection with loess-sulfur were effectively and easily usable method if farmers had only one of either hot water-disinfector or seed-disinfector. In addition, loess-sulfur is well-known to farmers, simple to manufacture method and cheap.

• Korean Journal of Weed Science
• /
• v.16 no.3
• /
• pp.200-209
• /
• 1996

It is assumed to be an efficient method for keeping a germinability of weed seeds as long as possible, if a secondary dormancy is not induced by transferring the seeds of which dormancy was broken in wetting condition into drying condition. To investigate its validity, two experiments were carried out on seeds of 9 weed species ; to find out the most effective storage condition in breaking the dormancy of each weed species and to know whether there is a decrease in the germinability by transferring into drying storage condition. The dormancy of Chenopodium album and Stellaria aquatica was released well under the drying condition, but that of Echinochloa crus-galli var. oryzicola by soaking in water. Other weed species were released from dormancy by storage in wetting condition. When the seeds stored in the wetting or soaking condition, are air-dried and then restored at room or low temperature, a decreasing tendency of germinability which might cause a trouble in using them practically, was not observed except on the seeds of Persicaria vulgaris. In the case of Persicaria vulgaris, the low germination since 3 month-storage seemed not to be caused by drying, because a decrease of its germinability was observed with increasing storage period in all of the storage conditions. In contrast, high germination was induced as the seeds of Echinochloa crusgalli var. oryzicola, which were not germinated during the storage in low temperature and wetting condition, were transferred into the room temperature and drying condition. These results suggest that this approach can be one of the efficient methods for keeping a good germinability as long as possible in most weed seeds.

• Korean Journal of Plant Resources
• /
• v.16 no.1
• /
• pp.74-81
• /
• 2003

To obtain multi-shoot using zygotic embryos dissected from ginseng seed, the embryos were cultured on MS medium supplemented with CPA and BA. Effective multi-shoot induction was achieved on 0.5mg/ t CPA and 1.0mg/ t BA treatment. Among the various plant growth regulator treatment, MS basal medium with 1mg/ t 2,4-D and 0.5mg/ t kinetin was more competent and could be induced 4∼6 shoots per one embryo. Also, the best condition for pre-embryoid induction from ginseng cotyledon so as to ginseng transformation appeared to 1mg/ t 2,4-D and 0.5mg/ t kinetin treatment. The kanamycin level to select transformants varied greatly by different explant tyues. The petiole explants with leaf and embryo could survived up to 100$\mu\textrm{g}$ / ml kanamycin concentration where as petiole explants without leaf died all at the level. Conclusionally, our results suggest that optimum kanamycin concentration for ginseng transformation using somatic embryos is about 75∼100$\mu\textrm{g}$ / ml concentration.

• Korean Journal of Environmental Agriculture
• /
• v.23 no.4
• /
• pp.258-263
• /
• 2004

Bioassay was employed to assess toxicity of soil which had been treated with sewage sludges for seven years. The $Microtox^{(R)}$ and root elongation test of lettuce (Lactuca Sativa.) elucidated that the intensity of soil toxicity was closely related with the types and amount of sewage sludges applied. Both bioassay methods proved to be useful in an assessment of soil toxicity and were consistent to some extent with the conventional chemical analysis methods. $EC_{50}$ values resulted from $Microtox^{(R)}$ were highly correlated with concentration of heavy metals in soils amended with sewage sludges : Cu ($r^2=\;0.86^{**}$), Cr ($r^2\;=\;0.84^{**}$), Ni ($r^2\;=\;0.83^{**}$), and Zn ($r^2\;=\;0.69^{**}$). This demonstrated that both bioassay techniques could be employed as tools for soil toxicity assessment when the soil was exposed to solid wastes such as sewage sludge.

• Korean Journal of Organic Agriculture
• /
• v.23 no.3
• /
• pp.481-495
• /
• 2015

The study researched germination of the plants and growth of Fungus according to concentration of aqueous extracts in order to provide basic data for developing natural agricultural resources by using Persicaria longiseta. The seed germination of Amaranthus spinosus was inhibited at 25% P. longiseta extract, while Agrostis stolonifera ssp. palustris was not affected at all concentrations tested. Especially, the seed germination rate and fresh weight of Trifolium incarnatum at 20% P. blumei extract were higher than those of control plot. The early growth of most receptor plant seedlings was promoted at 25% and 50% of P. blumei extracts, but the radicle growth of all receptor plants was significantly inhibited at > 25% of P. longiseta extract. The response of receptor plants to P. longiseta extract was different according to the plant species and the plant parts. The growth of plant pathogenic fungus in PDA medium showed an increasing inhibition tendency with increasing concentrations of P. longiseta extract. Especially, P. longiseta extract showed the greatest antimicrobial activity against Phytophthora infestans, Phythium graminicola, and Pythium venterpoolii. The content of total phenolic compound in P. longiseta was higher in leaves (1082.3 mg/L) but lower in roots (228.6 mg/L) and stems (207.8 mg/L), which is an allelopathic chemical. As these results are summarized, P. longiseta have competitive advantage because they release phenolic compounds with allelopathic effect and affect on germination, growth and fungi growth on underground flora compared to native plants and they have eligibility for natural herbicide and germicide.

• Korean Journal of Organic Agriculture
• /
• v.20 no.4
• /
• pp.619-630
• /
• 2012

Miscellaneous grain crops has been appeared as a well-being food and the demand of them are increasing recently. It is urgent to study especially about the functional materials of foxtail millet, common millet and sorghum. This experiment was conducted to evaluation and comparison several functional materials of fatty acids, anthocyanin content, total phenol content and DPPH assay of rice, and foxtail millet, common millet and sorghum produced organically so that these results would provide as a basic information for developing functional products by using miscellaneous grain crops. Total content of fatty acids was in order of foxtail millet (0.649%) and common millet (0.33%), sorghum (0.172%) and rice (0.111%) respectively. The content of unsaturated fatty acid was also in order of foxtail millet (0.511%) and common millet (0.269%), sorghum (0.122%) and rice (0.069%) respectively. Although there was no detection of anthocyanin content in rice, foxtail millet and common millet, sorghum showed high content of anthocyanin content. Sorghum of Mongdangsusu showed the highest anthocyanin content (137.5mg/g). In the total phenol content of rice, foxtail millet, common millet and sorghum, rice of Chucheongbyeo had high content ($13.70{\mu}g/g$) whereas Daeanbyeo was the lowest content ($10.07{\mu}g/g$). Foxtail millet of Hinchajo, common millet of Byeorukgijang and sorghum of Chalsusu showed the highest total phenol content of $25.8{\mu}g/g$, $69.4{\mu}g/g$ and $682.2{\mu}g/g$ respectively. In the average of total phenol content among rice, foxtail millet, common millet and sorghum, foxtail millet, common millet and sorghum showed $12.25{\mu}g/g$, $16.95{\mu}g/g$, $51.01{\mu}g/g$ and $447.4{\mu}g/g$ of total phenol content respectively. The average of total phenol content of sorghum was $26.3{\mu}g/g$. It is 36.3 and 26.3 times higher compared with rice and foxtail millet respectively. In the antioxidant activity of seeds by DPPH(1,1-diphenyl-2-picrylhydrazyl) assay for rice, foxtail millet, common millet and sorghum, rice of Chucheongbyeo, foxtail millet of Ganghywajo and common millet of Geumeungijang showed the highest antioxidant activity with 3.6%, 4.78% and 13.4% respectively. Antioxidant activity of sorghum ranged from 88.47 to 90.11%. The average of antioxidant activity among four crops, the highest antioxidant activity was obtained from sorghum (89.50%) and the next was common millet (6.13%), foxtail millet (2.43%), and rice (1.60%) in their order of antioxidant activity. The average of antioxidant activity of sorghum showed 55.9, 37.0 and 15times higher compared with rice, common millet and foxtail millet respectively.

• Korean Journal of Organic Agriculture
• /
• v.29 no.1
• /
• pp.97-109
• /
• 2021

Plant parasitic nematodes are causing significant damage in crop production. There is a need to develop eco-friendly nematicide that reduces the damage of nematode and has little effect on the environment and human. In this study, we have isolated a substance having nematicidal activity from Ginkgo biloba L. outer seedcoat. Studies of G. biloba L. outer seedcoat are insufficient compared to the seed and leaves due to their odor and toxicity. The dried G. biloba L. outer seedcoat was extracted with dichloromethane:methanol (1:1) and fractionated into hexane, ethyl acetate and H₂O. Four steps TLC were performed from EtOAc fraction to purely isolate GB4-3 with nematicidal activity. To compare nematicidal activity, G. biloba L. seedcoat methanol extract and purified GB4-3 were investigated in terms of treatment concentration and time. As a result, the nematicidal activity increased with concentration and time. In the place treated with 20 ㎍/mL of crude G. biloba L. seedcoat MeOH extract, strong activity appeared after 12 hours, and 46% nematicidal activity shown after 18 hours. About 69% of nematicidal activity was confirmed in the place where GB4-3 purified from outer seedcoat was treated with 20 ㎍/mL, and the possibility of development as nematicide was very high. This study could be used as a basic data for the development of a nematode preparation from G. biloba L. outer seedcoat.

• Korean Journal of Weed Science
• /
• v.7 no.1
• /
• pp.90-97
• /
• 1987

An attempt was done at the Yeongnam Crop Experiment Station in 1986-'87 to obtain herbicide tolerant variant through cell culture. Immatured rice grain was more rapidly and efficiently formed callus in dehulled rice culture method for both rice cultivar types, Tongil type (Indica/Japonica) and Japonica-type. However, Japonica-type cultivar was generally superior than Tongil-type Cultivar in callus formation. Expression rate of herbicide tolerant variant varied depending upon rice cultivar, plant species and herbicide properties. In case of Nagdongbyeo (Japonica) at the first subculture, 46.3% of total callus pieces appeared as herbicide tolerant variant in herbicide media of CGA142464 and followed by NC-311 (11.6%), Butachlor (7.5%), 2.4-D (2.1%), Quinclorac (0.89%), and Propanil (0.25%), in order. This degree of appearance of herbicide tolerant variants rapidly increased as passage of subculture was advanced. Herbicide tolerant callus hardly regenerated as normal plant even though large variations exhibited among culture media.