As the average temperature on Earth increases due to global climate change, crops are further needed to overcome this issue. Since sweet potato has high yield potential, can grow in harsh environments, and contains abundant nutrients, it is a potential substitute food in response to environmental crises. Compared to grains such as rice and barley, sweet potato has a lower glycemic load and contains various natural antioxidants, showing a variety of physiological functions. Thus, sweet potato is in the spotlight as a healthy food. Although domestic sweet potato production continued to decrease from 1990 to 2010, its production was maintained or slightly increased until 2020 due to the changes in consumers’ dietary habits that emphasize health. In this regard, steamed or roasted sweet potatoes were consumed as a snack substitute in the previous eating form. Furthermore, sweet potato starch has been used in various industries, including food. Therefore, this study intends to discuss the value of sweet potatoes as food, the production trend and cultivation method of sweet potatoes in South Korea, and the industrial application of sweet potatoes.

본 시험은 콩 안정생산 재배법 확립을 위한 Methyl Sulfony Methane (MSM) 시용방법별 생육특성 및 수량을 알아보기 위하여 2020∼2021년에 경상국립대학교 내동 부속농장에서 ‘대원콩’을 국립종자원으로부터 분양받아 수행하였다. 본 시험의 MSM 처리는 2020년에 MSM 시용시기에 따라, 100% 농도로 하여, 기비(BF, basal fertilizaton)+추비1회, 기비+추비2회, 추비1회, 추비2회, 추비3회, 무시용구로 처리하였고, 2021년에는 2020년도에 선발된 시용시기에서의 MSM 시용량에 따라, 기비+추비 50%, 기비+추비 100%, 기비+추비 200%, 추비 50%, 추비 100%, 추비 200%, 무시용구로 설정하였다. 2020년 생육특성 조사에서는 추비시용 전 R1∼2기에 MSM을 기비한 처리구에서 초장, 경태 및 NDVI 값이 높게 나타났고, 2021년 초장에서도 가장 높게 나타났다. 추비시용 후 R6기의 2020년 초장은 무처리구 및 추비1회를 제외한 모든 처리구가, 경태는 추비3회 처리구 및 기비+추비2회 처리구가, Fv/Fm 은 기비+추비2회 처리구가 가장 높았고, 2021년 또한 기비+추비3 200% 처리구에서 초장 97.9cm, 경태 17.2 mm, 분지수 7.44 개, Fv/Fm 값 0.802 로 가장 높은 값이 나타났다. 또한, 수량구성요소는 2년간 MSM 시용의 증가에 따라 주당협수 및 협당립수에서 차이를 보여, 종실수량에서도 2020년에 추비3회 처리구 및 기비+추비2회 처리구가 각각 225, 228 kg·10a-1로 가장 많은 수량이 나타났고, 2021년에는 기비+추비3 200% 처리구에서 382 kg 10a-1로 수량이 가장 많은 것으로 나타났다. 따라서, 2년간의 시험에서 MSM 시용의 증가에 따라 수량도 증가하여, 기비+추비3 200% 처리구에서 최대 21.8%의 증수효과가 나타났다.

본 연구는 평야지 논토양에서 찰옥수수/콩을 활용한 2모작 재배방법을 개발하기 위한 기초자료로 활용하기 위하여, 2년간 (2019~2020년) 파종시기별 경운방법 및 재식방법에 따른 찰옥수수와 콩의 생육 및 수량 특성을 알아본 결과는 다음과 같다. 1. 찰옥수수와 콩의 생육기간 중 토양 수분함량 변화에서 과잉수 정체기간은 쟁기+로터리 처리와 이랑너비가 좁을수록 짧게 조사되어, 쟁기+로터리60 cm 처리구에서 가장 짧았다. 2. 모든 시기의 생육특성 조사에서 찰옥수수는 2차파종 쟁기+로터리60 cm 처리구가 연차간 초장과 경태가 가장 길었고, 엽수도 가장 많았으며, 엽색도도 가장 높았으며, 콩은 1차파종 에서 쟁기+로터리60 cm 처리구가 연차간 모두 초장, 경태, 엽수 및 엽색도의 조사값이 가장 높았다. 3. 찰옥수수 수량에서는 2차파종 쟁기+로터리60 cm 처리구가 연차간 모두 1,245, 1,262 kg/10a 로 가장 많았고, 콩은 1차 파종 쟁기+로터리60 cm 처리구에서 223, 220 kg/10a 로 가장 많았으며, 다음으로 1차파종 쟁기+로터리120 cm · 로터 리60 cm 처리구 및 2차파종에서 쟁기+로터리60 cm 처리구에서 186~210 kg/10a 로 많았다. 4. 생육조사 및 수량평가에서 파종시기와 이랑너비에서 뚜렷한 차이를 보였으며, 평야지 논에서 찰옥수수와 콩 2모작 재 배시 쟁기+로터리하여 60 cm의 고휴에 1열로 찰옥수수는 4월 초에 파종, 콩은 찰옥수수의 수확시기에 맞춘 7월 중순 파종 하여 재배하는 것이 유리할 것으로 생각된다.

Background : This study was conducted to serve as a basis for the production of high quality organic cultivation Platycodin grandiflorum Ridix roots by analyzing the content of saponins according to organic fertilizer for organic farming. Methods and Results : Platycodin grandiflorum Ridix was treated by with biodegradable film, rice husks, and sawdust, non-mulching (hand weeding). A root of Platycodon grandiflorum were analyzed saponins using HPLC harvested on October. Content of Plantycodin D3 was an average of 68.5 ㎎/100g, which appeared as 111.2 ㎎/100g highest content in the sawdust treated. Deapioplatycodin D showed the highest 48.1 ㎎/100g in the sawdust treated. The content of Platycodin D was shown to 246.2∼373.8 ㎎/100g, the highest values were observed in non-mulching, it showed the lowest value in the rice husks treated. The content of Polygalacin D showed up to 156.0 ㎎/100g in the non-mulching as the biggest difference, the lowest value were 30.1 and 32.2 ㎎/100g in sawdust and rice husks treated. Large differences between fertilizers was not showed, but the overall saponin content of Platycodin grandiflorum Ridix were low in value compared to the control than organic fertilizers. Conclusion : Large differences between mulching materials was showed, thus the overall saponin content of Platycodin grandiflorum Ridix was highest in value compared to non-mulching than sawdust treatment. Mulching Platycodin grandiflorum Ridix with sawdust was an effective method for improving saponin contents.

Background : This study was performed to know the effect of mulching materials on the growth and root characteristics of Platycodin grandiflorum Ridix. Methods and Results : Platycodin grandiflorum Ridix was treated by with biodegradable film, rice husks, and sawdust, non-mulching (hand weeding). To measure the fresh weight and length, thickness and the number of fine root of the Platycodin grandiflorum Ridix roots harvested in October. Root length appeared in the biodegradable film and sawdust were 27.5 and 26.7㎝ longest, rice husks was the shortest 22.0㎝. Diameter at the thickest showed 30.9 ㎜ in biodegradable film, the following phrase appeared sawdust and rice husks application. The number of fine-root was investigated in biodegradable film most piece 36.0. Fresh weight, which is directly related to yield were biodegradable film to 130 g the highest in the number of fine-root and the longest root length. Conclusion : For the increasing the yield that Pharmacological effect, biodegrada

Background: This study determined the effects of mulching, an environment friendly organic cultivation method, on antioxidant compound contents and growth in Codonopsis lanceolata, commonly known as Deodeok. Methods and Results: C. lanceolata was treated by mulching with several different methods (a non-woven fabric, biodegradable film, or rice husks) and also treated with hand weeding. A non-treatment plot was used as a control. The growth and levels of weed control in C. lanceolata were better in plants cultivated under mulching treatments (non-woven fabric, biodegradable film, and rice husks) than in those under non-mulching treatments (hand weeding and non-treatment). The contents of antioxidant compounds, such as total flavonoids, phenolics, and anthocyanins, were highest under the biodegradable film treatment, followed by the nonwoven fabric treatment, rice husks treatment hand weeding, and non-treatment. There were identifiable differences in DPPH and ABTS activity in comparison to antioxidant compound content by solvent fractions. Mulching treatments resulted in higher DPPH scavenging activity in water and ethyl ether fractions and ABTS scavenging activity in n-butanol fractions than in other fractions, as opposed to hand weeding and non-treatment groups, although total activity of DPPH and ABTS did not increase with mulching treatments. Conclusions: Mulching C. lanceolata with biodegradable film and non-woven fabric is an effective method for improving plant growth and inhibiting the occurrence of weeds as well as for increasing antioxidant compound content and altering antioxidant activity.

Background : This study was conducted to determine the effects of mulching, an environmentally friendly organic cultivation method, on antioxidant compounds and growth in Codonopsis lanceolata. Methods and Results : C. lanceolata was treated by mulching with a non-woven fabric, biodegradable film, or rice husks, as well as hand weeding, and non-treatment. The growth and levels of weed control in C. lanceolata were better in plants cultivated under mulching treatments (non-woven fabric, biodegradable film, and rice husks) than under non-mulching treatments (hand weeding, non-treatment). The contents of antioxidant compounds, such as total flavonoids, phenolics, and anthocyanin, were highest under biodegradable film treatment, followed by non-woven fabric treatment, rice husks treatment, hand weeding, and non-treatment. DPPH and ABTS activity were able to identify to have differences their activity in comparison to antioxidant compounds content by solvent fractions. Mulching treatments produced a higher activity in water and ethyl ether fractions for DPPH scavenging activity and in n-butanol fractions for ABTS scavenging activity compared to other fractions, although total activity of DPPH and ABTS were not increased with mulching treatments. Conclusion : Mulching C. lanceolata with biodegradable film and non-woven fabric is an effective method for improving plant growth and inhibiting the occurrence of weeds as well as increasing antioxidant compound content and changing of antioxidant activity.

Background : This study was carried out to investigate the antioxidant activities and the contents of antioxidant compounds in extracts derived from 24 medicinal crops. Methods and Results : Dried plant materials were extracted by methanol. The extracts of each plant were evaporated under vacuum and stored in deep freeze at -20℃ until use. The levels of total phenolic compounds were much higher in Evening primrose, Houttuynia cordata, Chinaberry, Sumac, Gaeddongssuk, Giant knotweed and Dendropanax morbifera compared with other crops. On the other hand, the total phenolic compound levels in Safflower, Fleeceflower root, Gingko, Black nightshade, Saposhinikovia root, and Maize woody pith were relatively low. The total flavonoid contents were highest in Houttuynia cordata, followed byDendropanax morbifera, Gaeddongssuk, Aralia cordata and Evening primrose. DPPH activity was significantly higher in Gaeddongssuk, Sumac, Chinaberry, Dendropanax morbifera and Evening primrose, and ABTS activity was significantly higer in Sumac, Chinaberry, Evening primrose, Giant knotweed, Gaeddongssuk and Dendropanax morbifera than other plants. The antioxidant activities dertermined in all assays positively correlated with the total phenolic compoubds (0.619≤ r ≤0.895) and flavonoid contents (0.488≤ r ≤0.619) as well as among themselves (r=0.900). Conclusion : These results suggest that Evening primrose, Gaedongssuk, Sumac, Dendropanax morbifera, and Giant knotweed can be utilized as food additives and natural antioxidants due to their strong antioxidant activity.

Background : The root of Platycodin grandiflorum has been widely used as a crude drug or a dependent on the cultivation area and cultivation method. Therefore, this study was conducted to know the effect of organic fertilizer on the changes of antioxidents and antioxidant activity of Platycodin grandiflorum Ridix. Methods and Results : As basal fertilizer were treated before transplanting Platycodin grandiflorum Ridix with chemical fertilizer(Super21, 21-17-17, Namhae Chemical), mixed organic fertilizer, bacterial culture, fermented oil cake and manure in each trial of nitrogen based on 3㎏/10a criteria. The total polyphenol content was highest values were 15.5mg/g appear in the mixed organic fertilizers, the lowest were 9.1mg/g appeared in the manure and control. Flavonoid content showed the highest 15.3 mg/g in the mixed organic fertilizer, and investigated at the lowest 5.0 mg/g in the fermented oil cake. ABTS radical scavenging activity was the highest in was 65.7 mgTE/g in the chemical fertilizer, showed the lowest value in the control to 13.0 mgTE/g. Therefore, both flavonoid and polyphenol content showed a high value on organic fertilizers. Conclusion : Therefore, both flavonoid and polyphenol content showed a high value on organic fertilizers. It is determined that to have researches for a variety of antioxidants by the organic fertilizers made in the future.

Background : This study was conducted to serve as a basis for the production of high quality organic cultivation Platycodin grandiflorum Ridix roots by analyzing the content of saponins according to organic fertilizer for organic farming. Methods and Results : As basal fertilizer were treated before transplanting Platycodin grandiflorum Ridix with chemical fertilizer(Super21, 21-17-17, Namhae Chemical), mixed organic fertilizer, livestock manure, bacterial cultures and fermented oil cake in each trial of nitrogen based on 3 ㎏/10a criteria. A root of Platycodon grandiflorum were analyzed saponins using HPLC harvested on October. Content of Plantycodin D3 was an average of 40.6 ㎎ /100g, which appeared as 48.1 ㎎/100g highest content in the bacteria cultures treated. Deapioplatycodin D showed the highest 70.9 ㎎/100g in the control, the rest was investigated 28.1∼54 ㎎/100g. The content of Platycodin D was shown to 327.4∼373.8 ㎎/100g, the highest values were observed in mixed organic fertilizer, it showed the lowest value in the control. The content of Polygalacin D showed up to 336.7 ㎎/100g in the manure as the biggest difference, the lowest value were 54.5 and 74.2 ㎎/100g in bacterial cultures and control. Large differences between fertilizers was not showed, but the overall saponin content of Platycodin grandiflorum Ridix were low in value compared to the control than organic fertilizers. Conclusion : For the increasing the yield that Pharmacological effect, organic fertilizer is effective to increase the number of fine-root high which high contented with saponins.

Background : This study was performed to know the effect of organic fertilizers on the growth and root characteristics of Platycodin grandiflorum Ridix. Methods and Results : As basal fertilizer were treated before transplanting Platycodin grandiflorum Ridix with chemical fertilizer(Super21, 21-17-17, Namhae Chemical), mixed organic fertilizer, bacterial cultures and fermented oil cake, manure in each trial of nitrogen based on 3 ㎏/10a criteria. To measure the fresh weight and length, thickness and the number of fine root of the Platycodin grandiflorum Ridix roots harvested in October. Root length appeared in the mixed organic fertilizer and chemical fertilizer were 25.3 and 24.0 ㎝ longest, oil cake was the shortest 15.3㎝. Diameter at the thickest showed 26.6 ㎜ in chemical fertilizer, the following phrase appeared bacterial cultures and mixed organic fertilizer application. The number of fine-root was investigated in mixed organic fertilizer and chemical fertilizer most pieces 20.0 and 17.0. Fresh weight, which is directly related to yield were mixed organic fertilizer to 55.7 g the highest in the number of fine-root and the longest root length. Conclusion : For the increasing the yield that Pharmacological effect, organic fertilizer is effective to increase the number of fine-root high which high contented with saponins.

Background : Platycodon grandiflorum radix used as a therapeutic agent for lung and respiratory diseases in traditional Korean medicine. The saponin and sugar content in P. grandiflorum root is dependent on the drying temperature and method. In this study, we investigated saponins and antioxidant contents in dried P. grandiflorum roots either not cut or cut to different lengths. Methods and Results : P. grandiflorum roots were either cut to 0.5, 1.0 or 2.0 ㎝ in length or left uncut. They were dried at 45℃ and the effect of antioxidant substances, antioxidant ability, and saponin content were investigated. P. grandiflorum roots rapidly dried out when cut to short lengths. The saponin contents (platycodin D, polygalacin D, and deapioplatycodin D) was highest in the uncut P. grandiflorum roots. When the cut lengths were long, the levels of polyphenolic compound increased. However, 2,2'-azinobis- 3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities were higher in the samples cut to shorter lengths. Conclusions : These results suggested that the saponin and antioxidant content of P. grandiflorum roots could be maximized by controlling the drying rate of the roots via adjustments to the root cutting length.

A field experiment was carried out to observe the weed control effects of vetch and to evaluate vetch characteristics on clay loam soil in no-till direct-sown rice-vetch cropping systems. The effects of weed control, forage productivity, and N content of vetch plants were investigated. With the progress of plant growth, density of Chinese milk vetch (Astragalus sinicus L.) gradually decreased, but densities of foxtail and other weeds decreased steeply due to the depression by the over-shaded vetch canopy in a no-till direct-sown rice-vetch cropping paddy field. The vetch density in tillage systems was lower than in notillage cropping systems. Lower vetch density occurred with an increase in foxtail density and other weeds. Weed control effect increased by the progress of vetch growth, which indicated that the vetch canopy over-shaded the weeds. Vetch straw was degraded rapidly submergence after with water at the time of wet sowing of rice. Early harvesting of vetch seed resulted in lower seed germination. To acquire enough seedlings without re-sowing, the harvesting of seed should be delayed at least 28 days after the flowering stage in order to ensure the vetch population is sustainable in a no-till direct-sown rice-vetch cropping system. In order to improve the survival of vetch plants, vetch seeds should germinate from the heading .stage to before the full-ripening stage of rice plants. To enhance the percent of over-wintering survival, vetch seeds should germinate no later than the end of October in southern Korea. The dry weight of vetch plants increased with the progress of vetch growth until the flowering stage but N content decreased for 30 days from before the flowering stage (2.9%) until the ripening stage (1.8%). We concluded that Chinese milk vetch could have an effect on weed control before the flowering stage, sustainability without re-sowing of seed annually, and effective green manure for rice pre-crop in no-till direct-sown rice-vetch relay cropping systems.

An experiment was carried out using pots to investigate the effects of Chinese milk vetch on the seedling establishment and growth in rice. Four irrigations with five-day intervals and three different levels of vetch straw were investigated. Significantly higher panicle numbers were obtained in vetch-treated pots. Vetch levels were non-treatment as checks, vetch with top removed, root plus shoot 7.5 ton/ha, and root plus shoot 3.0 ton/ha. The time for complete degradation of vetch straws was reduced from 10 days to 5 days as submerged time was delayed, and was affected by the amount of mulched vetch straws. As the mulched vetch amount increased, the time for a complete degradation was extended from 4 days to 12 days. Grain yield and its components were significantly affected by irrigation time and mulched vetch amount. Effectively controlled, lowered reduction damage from the degrading vetch straw, irrigation date and vetch amount were the most important factors for the improving of seedling establishment in direct-sown rice.

Uptake, assimilation and translocation of nitrogen and dry matter assimilation and translocation in ten rice cultivars were observed in no-till direct-sown rice-vetch cropping system. There was a large degree of variation in N-uptake, grain yield, nitrogen translocation efficiency and dry matter assimilation and translocation in tested rice cultivars. Forty kg N/ha base, as compound fertilizer (21-17-21% of N-P-K) three weeks after sowing and 30 kg N/ha top-dressed at panicle initiation stage as in the form of (NH4 )2 CO2 was applied. ‘Newbounet’, ‘Daesanbyeo’, and ‘Hwayeongbyeo’ showed higher translocation efficiency. The contribution of pre-heading dry matter assimilates to grain ranged from 33% to 99% of dry grain weight. Dry matter of ‘Calrose 76’ was lower than Newbounet but N content was higher in Calrose 76 than Newbonnet. By maturity, N content in vegetative parts declined considerably more than dry matter, vegetative and reproductive parts, N translocation efficiency, and N harvest index. Nitrogen translocation efficiency was greater in ‘Nonganbyeo’, Daesanbyeo, and Newbounet. Grain N concentration was positively correlated with N concentration or N content of the vegetative parts at heading in Nonganbyeo, ‘Dasanbyeo’, ‘Dongjinbyeo’, and Newbonnet. These results indicated that the greater amount of dry matter and N accumulated before heading stage, the higher translocation rates of dry matter to grain and the greater net losses at maturity.