Finding alternative and renewable energy sources has become an important goal for plant scientists, especially with the demand for energy increasing worldwide and the supply of fossil fuel being depleted. The most important biofuel to date
is bioethanol which is produced from sugars (sucrose and starch) found in corn and sugarcane. Second generation bioethanol is targeting studies that would allow the use of the cell wall (lignocellulose) as a source of carbon by non-food plants. Plant scientists, including breeders, agronomists, physiologists and molecular biologists, are working towards the development of new and improved energy crops especially, how to design crops for bioenergy production and increased biomass generation for biofuel purposes. This review focuses on: i) the current status of first generation bioenergy production, ii) the limitations of first and second generation bioenergy, and iii) ongoing research to overcome challenging issues in second generation bioenergy.
Total phenolic content, total anthocyanin content and antioxidant activity were analyzed from rice samples collected in Korea, Japan and China. The results showed that the total phenolic content and free-radical scavenging activity differed
significantly in these rice lines. The correlation between content and activity was subsequently investigated. The results showed that in black rice, anthocyanin was the major phenolic component and that both phenolic content and anthocyanin content were closely correlated with free-radical scavenging activity. Reverse Phase High Performance Liquid Chromatography (RP-HPLC) data showed that cyanidin-3-O-glucoside and peonidin-3-O-glucoside composed about 90% of the total anthocyanin content in black rice and in red rice. In the red rice extract, the total phenolic content produced a high correlation coefficient with antioxidant activity but correlated very poorly with the total anthocyanin content. The OD458 and the OD500 values which represent the proanthocyanidin content of the rice extract, produced high correlation coefficients with antioxidant activity and total phenolic content. These results suggest that the OD458 and the OD500 values can be used to evaluate the quality of red rice. In addition, based on the data obtained, a competitive accumulation model of anthocyanin and proanthocyanidin in black and red rice was proposed.
Late blight caused by Phytophthora infestans is historically a serious epidemic disease in potato and tomato
cultivations. Accession L3708 (Solanum pimpinellifolium), a new source for late blight resistance was identified in AVRDC, and carries the resistance gene, Ph-3, incompatible to P. infestans race 3. The AFLP markers linked to Ph-3 were previously developed from the L3708 accession (Chunwongse et al. 2002). To facilitate tomato breeding with the Ph-3 gene, an attempt was made to convert AFLP markers to sequence-characterized amplified region (SCAR) markers. Among 6 AFLP markers, only one AFLP marker, L87, was successfully converted to SCAR marker. The resistance-specific 230 bp AFLP fragment was cloned and sequenced, and the PCR primer amplifying a 123 bp fragment was designed. This SCAR marker could discriminate resistant and susceptible individuals with high stringency. The developed SCAR marker could be used for the marker assisted-selection in tomato breeding programs.
The objective of this study was to map gene/QTL for photoblastism in a weedy rice (photoblastic rice: PBR) using DNA markers. Light-induced effect on germination of seeds was compared among three accessions (Oryza sativa L.), PBR, Milyang 23 and Ilpum. Results showed that PBR seeds started to show photoblastism during seed development, different from Ilpum and Milyang 23. Frequency distribution of germination in the F4 lines from crosses between Ilpum and PBR and, Milyang 23 and PBR revealed bimodal distributions suggesting that photoblastism was controlled by a few genes. Bulked segregant analysis using F4 populations derived from the above two crosses was conducted to identify gene/QTL for photoblastism. Two QTL were identified on chromosomes 1 and 12 explaining 11.2 and 12.8% of the phenotypic variance, respectively. Two QTL were further mapped between two SSR markers, RM8260 and RM246 on chromosome 1, and between RM270 and 1103 on chromosome 12. It is noteworthy that two QTL for photoblastism were colocalized with the QTL for seed dormancy reported in the previous QTL studies. The clustering of two genes for photoblastism and dormancy possibly indicates that these regions constitute rice phytochrome gene clusters related to germination. Because PBR has a low degree of dormancy, a pleiotropic effect of a single gene controlling dormancy and photoblastism can be ruled out. The linked markers will provide the foundation for positional cloning of the gene.
The mutants of sugary-2 (su-2), floury (flo), shrunken-1 (shr-1), and dull-1 (du-1) were crossed to waxy (wx) to
produce F2 seeds. Chi-square analysis on the segregating ratio of the F2 seeds revealed that flo, su-2, and shr-1 were independently transmitted with wx, while wx was epistatic over du-1. The floury and sugary-2 were crossed to Hwasunchalbyeo, a waxy variety, and then the F4 of floury-waxy and sugary-2-waxy seeds were developed, respectively. As the parents phenotypes of sugary-2 and floury, the grains of these two lines showed lower hardness and grain weight than normal grain of Hwacheongbyeo. For alkali digestive value (AVD), the sugary-2-waxy showed lower ADV than Hwacheongbyeo. For the gel consistency of grain flours, the floury was medium like Hwacheongbyeo, while those of the sugary-2, floury-waxy, and sugary-2-waxy were soft like Hwasunchalbyeo. The amylose contents in the grains of the sugary-2 and floury were decreased to ~15% whereas that of Hwacheongbyeo was 19.1%. All the lines showing waxy endosperm (Hwasunchalbyeo, floury-waxy, and sugary-2-waxy) showed less than 4% amylose contents. Interestingly, the free sugar content in the brown rice was increased to 9.27% in the sugary-2-waxy, showing transgressive segregation phenomenon where the free sugar contents in its parents, sugary-2 and Hwasunchalbyeo, were 5.98% and 3.98% respectively. Also, the floury-waxy showed transgressive segregation phenomenon, containing 6.15% of free sugar content in the grains
본 연구는 대규모 GMO 격리포장에서 비타민 A 영양성분이 강화된 황금벼의 안정성 평가에 대한 가이드라인 및 프로토콜을 개발하고자 모본으로 사용된 ‘낙동’을 대조로하여 수행하였다. 경북대학교 농업생명과학대학 GMO 실습격리포장에서 총 사용면적 4,700 m2에서 황금벼와 모품종인 ‘낙동’에 대해 거미류를 포함한 곤충류 다양성을 조사하였다. 조사기간동안 채집된 개체들은 기능별로 해충군, 천적군, 거미군으로 크게 구분하여 계수하였으며, 조사된 개체군의 해충
본 실험은 곡류 작물중에서 육종의 소재로써 많은 장점을 지닌 호밀을 Gimsa C-분염법과 FISH기법을 이용하여 구성이질 염색질과 5S와 18S-26S rRNA 유전자의 염색체상의 위치를 확인하고자 본 실험을 수행하였다. 그 결과를 요약하면 아래와 같다.
1. C-분염의 분석 결과 7쌍의 호밀의 염색체 중에서 1, 2, 3과 7번 염색체는 중부염색체 이었고, 4, 5과 6번 염색체는 차중부염색체 이었다. 1번 염색체는 2차 협착부위로 동원체를 지니고
국내에서 육성된 178개 품종을 이용하여 12개 이삭형질에 대한 검토 결과는 다음과 같다. 통일형이 자포니카형보다 이삭길이는 길었고 이삭목은 두꺼웠다. 또한 수당립수, 총지경수, 2차 지경수, 2차 지경 총립수, 2차 지경 평균립수 및 1차 지경당 2차 지경수 각각에서 많았다. 반면에 자포니카형이 통일형보다 이삭추출은 양호하였고 1차 지경 평균립수도 약간 많았다. 12개 이삭형질 값을 가지고 평균 연결법을 이용하여 178개 품종을 대상으로 군집분석을 한
본 연구는 우리나라와 중국 그리고 파키스탄에서 수집한 재래종 조 계통들에 대하여 형태적 특징에 의한 유전적 변이성 연구를 수행하였다. 그 결과 우리나라 및 중국, 파키스탄의 조 계통들은 다음과 같은 형태적 변이를 나타내었다.
1. 형태적 특성조사에 의하면, 우리나라에서 수집한 조 계통들은 중국과 파키스탄에서 수집한 계통들보다 출수기가 늦었고, 초장이 크고, 이삭이 긴 특성을 나타내었다. 반면에 파키스탄에서 수집한 계통들은 출수기가 빠르고, 초장이 작고,
시클라멘의 꽃 및 꽃눈의 색, 잎의 모양과 무늬 등의 질적형질에 대한 유전 분석을 위하여 이들의 특성이 다른 계통을 교잡한 후, F1, F2 및 여교잡 세대에서 분리비를 조사하였다. 화색은 F1이 양친의 중간색을 나타냈고, F2는 자방친 화색: 중간 색(F1과 동일): 화분친 화색이 1: 2 : 1로 분리되어 한 쌍의 대립유전자가 불완전우성으로 유전하는 것으로 나타났다. 꽃눈 색은 흰색 × 빨간색 계통의 조합에서 F1 이 빨간색으로 나타났고, F2에서