Sae-Jung Suh

Difference of Starch Characteristics of Sweetpotato (Ipomoea batatas (L.) Lam) by Cultivated Regions

We investigated out the effect of cultivation region on the physicochemical characteristics of starch in six sweetpotato cultivars. The following sweetpotato cultivars were analyzed: Daeyumi, Shingeonmi, Jinhongmi, Shinyulmi, Yulmi, and Yeonhwangmi. Samples were cultivated in Muan, Iksan, Nonsan, Boryeong and Hamyang. The soil texture was found to be sandy loam in Muan, Iksan, and Boryeong, sandy clay loam in Nonsan, and loam in Hamyang. The starch content of the sweetpotato was higher in Muan than in Hamyang. The amylose content was 22.3-30.9%, and the highest amylose content was found in samples from Iksan. Rapid viscosity analysis showed that the samples from Hamyang had the lowest values of pasting temperature, while samples of the Daeyumi cultivar had the highest values. Thermal analysis with a differential scanning calorimeter showed that the Muan samples had the highest values of onset temperature, maximum peak temperature, and completion temperature, and the samples from Hamyang had the lowest values. There was no difference between the cultivation regions or the cultivar in the X-ray pattern of the starch or its appearance in scanning electron micrographs. Therefore, the results of this study confirm that cultivation region and cultivar play an important role in determining the quality of sweetpotato and the physicochemical characteristics of sweetpotato starch.

Review of property and utilization of oil crop for biodiesel

Abstract The demand for fuel and energy resources continues to grow due to increased consumption and emerg-ing economies in all parts of the world. With this increase in demand, crude oil prices in the international market has jumped dramatically. Global warming, which is a conse-quence of increasing greenhouse gas (GHG) emissions, has become scientific, social, and political concerns. To cope with global warming and energy crisis, cost-competitive biofuels are urgently needed. In addition, development of an infrastructure, which supplies energy stably and diversifies energy resources, as well as new cost-saving technologies should be developed to reduce the costs of producing biofuels. Due to high oleic acid content, rapeseed ( Brassica napus L.) is currently the potential feedstock for biodiesel production in temperate zone region and the production and use of rapeseed oil is already commercialized in Europe. In Korea double-cropping (rice and rapeseed) became more prevalent because it reduces competitions from land constraints. Pro-duction of rapeseed as a biodiesel feedstock may reduce the influence of rising oil prices and nation’s dependence on imported petroleum and increase job opportunities and farm incomes.

Current status on Miscanthus for biomass

Abstract The carbon dioxide concentration of the atmo-sphere is projected to increase by almost 50% over the first 50 years of this century. The major cause of this increase is continued combustion of fossil fuels. As a result, the sig-nificant changes in climate that have already occurred will be amplified, in particular a global temperature increase. Re-newable energy production has a central role to play in abating net CO 2 emissions to a level that will arrest the development of global warming. Especially, biomass crops are becoming increasingly important as concerns grow about climate change and the need to replace carbon dioxide- producing fossil fuels with carbon-neutral renewable sources of energy. To succeed in this role, biomass crop has to grow rapidly and yield a reliable, regular harvest. A prime candidate is Miscanthus , or Asian elephant grass, a perennial species that produces over 3 metres of bamboo-like stems in a year. Miscanthus species are typically diploid or tetraploid. Hybrids between species with different ploidy levels result in the highly productive triploid hybrids,

Weeding Effect of Using Soybean Cake and Cultivating Weeder Together in Rice Bran Farming

ABSTRACT This study was conducted to improve weeding effect by rice bran farming technique. In the weeding effect experiment by application timing control of rice bran and soybean cake, weeding efficacy was the highest at the treatment of conventional application of rice bran. The treatment of soybean cake with rice bran was unfavorable, but Echinochloa crus-galli occurred little at the treatment of soybean cake at 5 days after transplanting, so it is thought that further study about inhibitor of early E. crus-galli occurrence in soybean cake is necessary. Cultivating weeder was effective at the treatments of rice bran and soybean cake together, of which weed occurrence was more than conventional rice bran, and precise experiments about cultivating weeding time and method will be necessary.Key words: cultivating weeder; rice bran; soybean cake; weeding effect. 서 언 최근 친환경농업에 대한 관심이 높아짐에 따라 농업 환경에 대한 부하를 최소화하려는 노력이 점점 증가하고 있다. 우리나라는 2013년까지 2003년 대비 화학비료와 농약 사용량을 40% 줄인다는 계획 하에 종합병해충 관리시스템 도입과 화학비료 줄이기 및 친환경농업 확대 등 다양한 시책을 시행하고 있다(농촌진흥청 2004). 그 중에서 주목받고 있는 방법 중 하나가 쌀겨농법이다. 이것은 일본에서 유기농 쌀 생산 농가들에 의해서 시작된 농법으로, 유기농의 가장 큰 문제인 잡초제거를 이 농법으로 일정부분 해결할 수도 있다는 점에서 도입하는 농가가 증가하고 있다(농업과학기술원 2005).