Youn-Ho Moon

A new genotype of Miscanthus sacchariflorus Geodae-Uksae 1, identified by growth characteristics and a specific SCAR marker.

Miscanthus is referred to as an ideal lignocellulosic bioenergy crop, which can be used to generate heat, power, and fuel, as well as to reduce carbon dioxide emissions. The new Miscanthus sacchariflorus genotype named Geodae-Uksae 1 was recently collected from damp land in southern Korea. This study investigated the growth characteristics of Miscanthus genotypes, and developed a specific, sensitive, and reproducible sequence characterized amplified region (SCAR) marker to distinguish new M. sacchariflorus genotype Geodae-Uksae 1 from other native Miscanthus species in Korea. Growth characteristics such as stem length, stem diameter, and dry weight of Geodae-Uksae 1 were greater than those of normal M. sacchariflorus. The genotypes within Geodae-Uksae 1 were had the highest genetic similarity. A putative 1,800-bp polymorphic sequence specific to Geodae-Uksae 1 was identified with the random amplified polymorphic DNA (RAPD) N8018 primer. The sequence-characterized amplified region (SCAR) primers Geodae 1-F and Geodae 1-R were designed based on the unique RAPD amplicon. The SCAR primers produced a specific 1,799-bp amplicon in authentic Geodae-Uksae 1, whereas no amplification was observed in other Miscanthus species. The SCAR marker could contribute to identify Geodae-Uksae 1 among native Miscanthus species. The new Miscanthus genotype Geodae-Uksae 1 has great potential as an alternative lignocellulosic biomass feedstock for bioenergy productions.

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).

Control Effect of Insecticides against Chilo suppressalis Walker of Native Miscanthus in Korea

Miscanthus are perennial rhizomatous grasses and considered as an ideal cellulosic bioenergy crop. Recently, it was reported that Miscanthus was damaged by the larvae of rice stem borer, Chilo suppressalis Walker, one of the most destructive pests of rice in Korea since the 1960s. This study was thus conducted to evaluate the insecticidal effects against rice stem borer in the Miscanthus cultivation fields for two years. The experiment consisted of four chemical agent plots, one environment-friendly agent plot, and untreated plot. Untreated plot showed significantly high damage of 50%, while Buprofezin·Tebufenozide and Carbosulfan·Methoxyfenozide treatment plots showed low damage rate of 2% with low larvae density of 1 and 2.3 larvae m−2, respectively. Damage rates of Tebufenozide, ChlorantraniliproleIndoxacarb, and environment-friendly agent(MatrineWood vinegar solution) were 15, 26, and 18%, respectively, which were lower than that of untreated plot but higher than those of Buprofezin·Tebufenozide and Carbosulfan·Methoxyfenozide. In conclusion, rice insecticides were effective against rice stem borer in Miscanthus field. In particular, the treatments with Buprofezin·Tebufenozide and Carbosulfan·Methoxyfenozide showed excellent control effects with control value of 93.3 and 95.2. However, further studies with different types of insecticides should be carried out for the selection of insecticides with more effective control of rice stem borer.