SRAP (Sequence-related amplified polymorphism) and ISSR (Inter simple sequence repeat) molecualr markers were used to evaluate the levels and patterns of genetic diversity among 45 collections of orchardgrass from four continents. Twenty-one primer combinations were used and 480 bands were produced in SRAP, of which 405(84.38%) were polymorphic. On the other hand, twelve primers were used to generate a total of 116 bands in ISSR, of which 116(87.07%) were polymorphic. The coefficient range of genetic similarity was 0.6248-0.9686 and 0.6116-0.9231 respectively. Based on cluster and principal component analysis on the genetic characteristics, all collections could be divided into four groups and five groups in two markers, respectively. According to the analysis of genetic diversity and relationships, the appropriate strategies for collection and conservation of germplasm resources also were discussed and scientific breeding with far genetic relationship materials in orchardgrass were suggested.
Forage production and water use efficiency (WUE) of Lucerne were investigated in three varieties at different water availabilities. Forage production decreased with the severity of soil water availability. At 50% field water capacity (FWC), forage production dropped but in two varieties, Algonquin and Longdong, was still high and from 75%FWC to 50%FWC, forage production in Longdong decreased at the least rate. The greatest leaf WUE was observed in Longdong at all soil water availabilities. From 75%FWC to 50%FWC, it increased in Longdong and Xinjiangdaye, but decreased in Algonquin. With the severity of water deficit, δ¹³C value increased in all three varieties. At the same water availability, the greatest value was observed in Longdong. It suggested that moderate water stress can improve WUE in Lucerne. Longdong is to some extent more efficient in water use and may be more drought-tolerant with more steady production at moderate water deficit.
An extract of Allomyrina dichotoma larva (ADL), one of the insects used most frequently in traditional Chinese medicine for the treatment of liver diseases such as hepatocirrhosis and hepatofibrosis, was assessed for antioxidant bioactivity in this study.
Ooencyrtus nezarae Ishii (Hemiptera: Encyrtidae) and Gryon japonicum Ashmead (Hymenoptera: Scelionidae) are two important egg parasitoids of soybean stink bug Riptortus clavatus, one of the most serious pests in Korea. On the verge of increasing severity of R. clavatus damage in other crops, now it is important to know temporal distribution of R. clavatus and its parasitoids throughout cultivation season of various crops. Seasonal occurrence of R. clavatus and its egg parasitoids is well studied in soybean. However, occurrence of spring populations has not been fully investigated. Therefore we placed pheromone trap with refrigerated eggs in barley and early soybean fields to record occurrence of both R. clavatus and its’ egg parasitism rate in 2008. Number of R. clavatus attracted in the trap was recorded every week, and host eggs collected same time were brought into laboratory for investigation of parasitism. R. clavatus was found to exist in barley on the first day of trap installation, i.e., May 11th. Number of R. clavatus reached highest level after mid July. Only G. japonicum emerged from the eggs collected from barley field whereas O. nezarae was dominant species emerged from the host eggs collected from soybean field. We found that not only R. clavatus infestation but parasitoid occurrence begins in early spring barley field.
A mathematical model was written for simulating the removal of phenol from wastewater in enzyme-loaded membrane reactor (EMR). The numerical simulation program was developed so as to predict the degradation of phenol through an EMR. Numerical model proves to be effective in searching for optimal operating conditions and creating an optimal microenvironment for the biocatalyst in order to optimize productivity. In this study, several dimensionless parameters such as Thiele Modulus (Φ2, dimensionless Michaelis-Menten constant (ξ), Peclet number (Pe) were introduced to simplify their effects on system efficiency. In particular, the study of phenol conversion at different feed compositions shows that low phenol concentrations and high Thiele Modulus values lead to higher reactant degradation.
아가, 청자, 대원의 세 가지 콩 품종이 톱다리개미허리노린재의 발육과 생식이 미치는 영향을 실내에서 비교하였고, 또한 이 세 가지 품종 간에 야외 발생소장을 비교하였다. 실내 실험에서 약충의 발육기간은 아가, 청자, 대원콩에서 각각 평균 14.5, 14.0, 14.6일이였고, 약충의 사망률은 각각 40.0, 51.3, 55.7%였다. 발육기간에서는 통계적 차이가 없었지만, 사망률에서는 아가콩에서 유의하게 다른 두 품종보다 낮았다. 성충의 생식능력으로 7일 동안 암컷이 산란한 알의 총 개수의 평균은 각각 67.8, 68.0, 67.7개였으며 통계적 차이는 없었다. 야외조사는 안동시 풍산면 소재 친환경 인증 포장에서 아가, 청자, 대원을 각각 3반복의 라틴방각법으로 배치하여 재배하였다. 7월 13일부터 10일 간격으로 8회 동안 알, 약충, 성충의 수를 각 처리구에서 임의로 30주를 조사하였다. 조사기간 전체 동안 발생 수는 알의 개수가 아가, 청자, 대원콩에서 각각 평균 18.3, 23.0, 23.7개, 약충은 각각 평균 8.0, 11.3, 17.3마리, 성충은 각각 평균 7.3, 21.3, 15.7마리가 조사되었다. 톱다리개미허리노린재의 알과 약충에서는 통계적인 차이가 없었지만, 성충은 아가에서 가장 적게 발생하였다. 이상의 결과로 새로운 품종인 아가콩은 다른 두 품종에 비해 톱다리개미허리노린재의 유충 생존율을 높였지만 성충의 발생은 다른 두 품종에 비해 적음을 알 수 있었다.
Chrysanthemum flower model trap (CFMT) developed to attract the flower thrips was evaluated for its optimal trap density that is required to manage the population of flower thrips in a strawberry greenhouse. CFMTs were installed in different rates per unit area (10m×5m), i.e., control (no trap), low (5 traps), medium (10 traps), and high (20 traps), in three different strawberry greenhouses at Namhoo, Andong. From each plot, 10 flowers were sampled every week from 16 May 2008 to 6 June 2008. Five traps were also randomly collected from each plot every week to record the number of flower thrips trapped. The seasonal number of both female and male thrips collected in the flowers was significantly lower in the plots with high density of traps compared to the control. In the plot with medium level of traps, less seasonal number of male F. intonsa were found in the strawberry flowers compared to the plot with low level of traps or control. When the numbers of thrips in the flowers were plotted against the numbers of thrips trapped in the CFMTs, significant correlation was found in female thrips only. However, there was no significant difference in seasonal number of male and female thrips trapped in the CFMTs randomly collected from the plots among the treatments. In conclusion CFMT used in medium or high density in the strawberry greenhouse reduced infestation of F. intonsa in the flowers and can be a good addition to integrated pest management tactics against anthophilous thrips.
The absolute age of lapilli tuff in sedimentary formation that contains dinosaur fossils in the Boseong area, Korea was determined radiometrically against volcanic rocks below and above the fossil-bearing horizons. The sanidine in the lapilli tuff below the fossil-bearing horizon (Seonso formation) has an 40Ar-39Ar age of 81.l±1.4Ma. The Pilbong tuff above Seonso formation has an 40Ar-39Ar age of 81.0±2.4Ma. An andesite dyke intruding all sedimentary units yields an 40Ar-39Ar age of 42.4±2.5Ma. Thus 81 Ma age can be regarded as the best estimate for the age of the Seonso Formation and the associated the dinosaur eggs. This age correlates well with dinosaur fossil finds in the Haenam and Koseong regions of Korea. The occurrence of dinosaur eggs and clutches attests to the existence of dinosaurs in southern Korea at least inCampanian times.
Batch sorption experiments were carried out for the removal of metylene blue from its aqueous solution using H3PO4 activated Acacia arabica carbon (AAC). The prepared activated carbon was characterized and was found as an effective adsorbent material. The operating variables studied were initial metylene blue concentration, AAC concentration and solution pH. AAC activated carbon posses a maximum sorption capacity for the range of initial dye concentrations studied (60~100 mg L-1). The sorption kinetics were analyzed using reversible first order kinetics, second order, reversible first order, pseudo-first order, and pseudo-second order model. The sorption data tend to fit very well in pseudo-second order model for the entire sorption time. The average pseudo-second order rate constant, KII and regression coefficient value were determined to be 0.0174 mg g-1 min-1 and 0.9977. The biosorption process also fit well to reversible I order kinetics with a regression coefficient of 0.9878.
The purpose of this paper is to evaluate the implementation of the UR Agreement on Agriculture in terms of commitment of major area and agricultural trade performance and to explain some issues of the current WTO’s Doha negotiation on agriculture with a prospect of the DDA negotiations.One of the great achievements of the Uruguay Round of trade negotiations was to bring agricultural sector of individual countries to the mainstream of GATT disciplines. Although the evaluation on the performance of the new trading rules under WTO seems differ between exporting and importing countries of agricultural products, the experience of implementing the URAA has revealed several weakness and shortcomings in agricultural reforms. Therefore agricultural sector will remain as an important negotiation area in the WTO DDA round. The ongoing DDA negotiations on agriculture will likely result in further reductions of trade-distorting domestic subsidies and termination of export subsidies as well as substantial reduction of tariffs and expansion of the market access.