Many important traits have been tagged allowing plant breeders to apply marker assisted selection (MAS) in rice. PCR itself is simple to set up, and requires little hands-on time. However, a crucial limiting step of MAS programs is the reliable and efficient extraction of DNA which can be performed on thousands of individuals. In this study, We describe a modification of the DNA extraction method, in which cetyltrimethylammonium bromide (CTAB) is used to extract DNA from leaf tissues for suitable MAS in rice. We followed the standard 2% CTAB extraction method in all the procedure. In addition we used the 1.2 ml 8-strip tube instead of 1.5 ml E-tubes to fit the 8-multichannel pipette and employ the 96 well plate to use the swing bucket centrifuge. Our modified CTAB DNA extraction method offers several advantages with respect to traditional and simple methods. 1) adult leaf samples collected in paddy field are applicable. 2) 96 leaf samples can be homogenized only one-time by using tungsten carbonate bead and 96well block. 3) semiautomatic loading method using 8-multichannel pipette from DNA extraction to electrophoresis of PCR products. 4) our system can extract about 400 leaf samples per day by only one technicion. Therefore, this method could be useful for marker assisted breeding in rice.

‘'Sinunbong 1’' is a japonica rice cultivar developed from the cross between “"Sangjubyeo”", high yield cultivar and ‘'Unbong 17’', cold tolerance at Honam Agricultural Research Institute (HARI), NICS, RDA, in 2005. This cultivar has a short grain shape and about 111 days growth duration from transplanting to harvesting in Korean climate condition. This cultivar shows high resistant reaction to the blast, but susceptible to bacterial blight and strip virus. This variety has cold tolerance, compared to Odaebyeo. The milled kernels of ‘'Sinunbong 1’' are translucent with non-glutinous endosperm. It has about 19.2% of amylose content and better palatability of cooked rice compared with ‘'Odaebyeo’'. The milled rice yield of ‘'Sinunbong 1’' is about 5.46 MT/ha under the standard fertilizer level of the ordinary transplanting cultivation. ‘'Sinunbong 1’' would be adaptable to the northern plain, mid-mountainous, southern mountainous of Korea.

‘'Hwangkeumnuri’' is a japonica rice variety developed and registered by the rice breeding team of Honam Agricultural Research Institute, NICS, RDA in 2006. This variety was derived from a cross between ‘'Milyang 165’' (Junambyeo) with good quality and high yield and HR14732-B-67-2-3 with multi-disease resistance. This variety has about 125 days growth duration from transplanting to harvesting in west-southern coast, Honam and Youngnam plain of Korea. It is about 76 cm in culm length and tolerance to lodging. In reaction to biotic and abiotic stresses, it shows resistance to blast, bacterial blight pathogen from K1 to K3 and stripe virus, but susceptible to other major diseases and insect pests. The milled rice of ‘'Hwangkeumnuri’' exhibits translucent, relatively clear non-glutinous endosperm and midium short grain. It has similar amylose content of 18.9% and lower protein content of 6.2%, and good palatability of cooked rice compared with ‘'Nampyeongbyeo’'. The milled rice yield performance of this variety is about 5.74 MT/ha in local adaptability test for three years. ‘'Hwangkeumnuri’' would be adaptable to west-southern coast, Honam and Yeongnam plain of Korea.

자포니카형 품종에서 벼멸구 저항성 육종의 효율을 향상시키고자 '삼강벼'/'낙동벼' BC5F5 세대의 여교잡집단(SNBIL)에서 개발된 DNA marker RM28493에 대하여 활용성을 검토한 결과는 아래와 같다. 1. 벼멸구 저항성 유전자 Bph1의 근동질 유전자 계통인 SNBIL61과 감수성인 주남벼가 교배된 약배양 집단에서 RM28493은 벼멸구 저항성 생물검정 성적과 일치하였다. 2. RM28493은 다양한 유전자원에서 벼멸구 저항성 유전자인 B

벼 바이러스병에 대한 최선의 방제책은 저항성 품종의 육성이라 할 수 있다. 저항성 품종의 육성을 위해서는 정밀하고 대량으로 검정 할 수 있는 검정법의 확립이 무엇보다 중요하므로 이를 위해 격리 검정망실을 건립 보독충을 방사한 후 이를 계대유지 하여 검정에 이용하였다. 망실내에 바이러스 보독충율 변이에서 연중 높은 보독충율을 유지하였으며, 매개충의 밀도도 검정에 충분하게 유지되었다. 망실을 이용한 바이러스병 저항성검정의 효율성은 줄무늬잎마름병은 92~100% , 오갈병은 100%의 검정효율을 보였으며, 이러한 대량검정법은 실내유묘검정과 고도의 정의 상관을 나타내어 포장검정의 대량검정과 실내유묘검정의 정밀도 등 장점을 겸비한 유용한 방법으로 확인되었다.

화영벼와 일품벼를 이용하여 벼멸구에 피해에 따른 농업적 특성, 수량 및 품질에 미치는 영향을 검토한 결과는 다음과 같다. 1. 벼멸구 피해지에서 간장 수장 및 수당립수는 차이가 없었으나, 등숙율 및 쌀수량은 무피해구에 비해 감소되어 출수기 이후의 피해가 큰 것으로 나타났다. 2. 현미의 외관품질 분석 결과 벼멸구 피해지의 정상립 비율은 감소하였고, 미숙립, 피해립 및 사미의 발생은 증가되었다. 3. 벼멸구 피해지의 쌀의 이화학적 특성 분석 결과 아밀로스 함량은 차이가 없었으나, 단백질 함량은 높았다. 최고 점도는 낮고 치반점도는 높았으며 취반시 호화특성이 불량한 것으로 나타났으며, 식미치는 낮아졌다.