This study aims to distinguish between various Ethiopian durum wheat varieties based on their genetic identity using chemical and morphological characterization of seeds. Combinatorial employment of five chemical tests on seeds showed marked qualitative variation among the test varieties, with high discriminatory potential noted for the standard phenol test, followed by the modified phenol and iodide tests. The modified phenol test was instrumental in further discriminating between the varieties that were not identified using the standard phenol test. Unlike the iodide and phenol tests, the NaOH and KOH tests did not show significant variation among the varieties. These results underscore the efficacy of phenol and iodide tests in differentiating between durum wheat varieties. Although the morphological traits were advantageous in seed characterization, they lacked discriminatory power compared with that of the chemical tests. This study concludes that a single test is inadequate for varietal discrimination; rather, a combination of chemical tests can augment the discriminatory potential.

Limonium tetragonum is a halophyte grown naturally in the coastal region in South Korea. This study was conducted to investigate the effects of salt concentrations on seed germination, seedling growth, and antioxidant capacity of L. tetragonum. Seeds were collected from naturally grown plants of L. tetragonum and those at full maturity were used in this experiment. All experiments were performed at 0%, 0.5%, 1.0%, or 2.0% of salt concentrations. Seed germination rate was highest as 86% at 20℃ and followed as higher in order of 25℃, 30℃ and 15℃. The germination rate was about 80% at 0% or 0.5% of salt concentration, but it was very low at the salt concentrations higher than 1%. Growth of L. tetragonum seedlings showed no difference in Hoagland solution containing NaCl in the range of 0% to 1.0% and seedlings survived at 2.0% of NaCl concentration. As the salt concentration increased, the content of Na+ in the shoot increased, but that of K+, Ca++, or Mg++ decreased. The antioxidant activity and the content of total polyphenol and total flavonoid in the shoot were similar at 0% and 0.5% of NaCl and were highest at 2.0% of NaCl concentration. In conclusion, performance of seed germination and plant growth of L. tetragonum was highest at 0% and 0.5% of NaCl concentration, and showed no difference in antioxidant activity, total polyphenol contents, and total flavonoid contents at the same salt concentrations.

밀×옥수수 원연교잡은 타 방법에 비하여 반수체 밀 육성에 매우 효과적이어서 외국에서는 밀 품종의 육종연한 단축 등을 위하여 많이 활용하고 있다. 본 연구에서는 국내 밀 품종(계통)과 옥수수 품종을 이용한 반수체 밀 생산체계를 구축하기 위하여 원연교잡에 사용하는 품종에 따른 반수체 생산 효율을 조사하였다. 자방친으로는 금강밀 등 총 5종의 품종과 5종의 F1계통을 사용하였고, 화분친으로는 강다옥 등 총 7종의 옥수수 품종을 사용하였다. 자방친으로 사용한 국산 밀 품종의 평균 종자 형성률, 배 형성률 및 반수체 식물체 재분화율은 각각 약 75%, 19% 및 8.4%이었다. 반수체 식물체 재분화율은 3.7∼9.8%의 분포를 보였는데, 조경이 가장 높았다. 밀F1 계통 자방친의 평균적인 종자 형성률, 배 형성률 및 반수체 식물체 재분화율은 각각 약 66%, 16% 및 6.6%이었다. 밀계통의 반수체 재분화율은 3∼10%의 분포를 보였으며 08WG074 계통이 가장 높았다. 한편, 7종의 옥수수 품종의 자방친(금강밀)에 대한 평균 종자 결실률, 배 형성률 및 반수체 식물체 재분화율은 각각 약 78%, 18%, 9.6%이었다. 반수체 재분화율은 7.6∼12.9%의 분포를 보였으며, 광평옥이 가장 높았다. 밀×옥수수 원연교잡에서 종자 결실률과 배 형성률은 자방친과 화분친의 품종에 따라 고도로 유의한 차이를 보였으며, 이들 형질의 품종간 차이는 자방친 품종보다는 화분친인 옥수수 품종 사이에서 더 컸다. 본 연구에서 조사한 품종 중에서는 광평옥, 강다옥 및 강일옥 품종이 밀×옥수수 원연교잡의 화분친으로서 우수한 결과를 나타내었다.

내염성과 관련 있는 벼의 CBF4 유전자(OsCBF4)를 벼에서 과발현 시켜 염 스트레스 조건에서 저항성이 증진된 내염성 유전자원을 개발하였다. RT-PCR을 수행하여 분리한 OsCBF4 유전자는 1,429 bp 크기의 뉴클레오티드로 274개의 아미노산으로 구성되었고, 벼의 다른 CBF 유전자와 33~49% 상동성을 나타내었다. 형질전환 식물체는 PCR과 Southern분석으로 OsCBF4 유전자의 벼 게놈 내 도입을 확인하였다. 전이 유전자는 벼 게놈 내에 1~4사본이 도입되었고, 선발된 형질전환 계통 모두에서 전이 유전자가 강하게 발현되었다. 염 스트레스 조건에서 형질전환 식물체는 비 형질전환 벼 보다 생육 정도가 양호하였으며, 특히 CBF4-10 계통은 염 처리 후 많은 식물체가 살아남았다. Real-time PCR 분석 결과 CBF4-10 계통은 120 mM NaCl 처리 시 전이 유전자 OsCBF4 전사체 발현이 잎에서 무처리 대비 약 3배 이상 증가하였다. 결론적으로 일반 벼에 도입된 OsCBF4 전이 유전자는 내염성 증진 기능이 있으며, OsCBF4 전이 유전자의 발현이 높은 형질전환 벼 계통은 내염성 벼 육종 소재로 이용할 수 있을 것으로 평가된다.

Phosphorus (P) is an important structural component and plays critical roles in the process of energy transfer and signal transduction. Effect of low P on carbohydrate metabolism was investigated at the transcription level via transcriptome analysis using the rice 60K oligonucleotide DNA microarrays. Two-week-old rice seedlings were grown under a low (32 μM) or high (320 μM) P condition for two weeks and leaves from the seedlings were used for transcriptome analysis. Expression of genes involved in carbohydrate metabolic pathways (eg. glycolysis, sucrose degradation and starch synthesis and degradation) was most significantly affected under low P. Under low P, most genes involved in glycolysis were intensively down-regulated, genes of starch biosynthesis and degradation pathway were up- or down-regulated, and many genes involved in sucrose biosynthesis were intensively up-regulated. In leaves under low P, glucose and pyruvate levels decreased, but sucrose and starch levels increased. These results suggest that carbohydrate metabolism is adjusted primarily through comprehensive transcriptional modulation of genes involved in the carbohydrate metabolic super-pathway.

밀가루와 면대 색이 밝은 품종의 육종효율을 증진하기 위하여 PPO 활성과 연관된 sequence-tagged site(STS) 분자표지인 PPO-05, PPO-16, PPO-18, PPO-30과 PPO-43을 이용하여 국내의 밀 품종의 PPO활성 수준과 유전자형 간의 관계를 분석하였다. Ppo-A1에 연관된 PPO-18이 국내 밀 품종의 PPO 활성 판별과 선발에 유용한 분자표지로 확인되었다. PPO 활성은 Ppo-A1b 유전자형 품종(0.446)이 P

Low temperature stress is one of the major negative factors affecting vegetative and reproductive growth of rice. To better understand responses of rice plants to low temperature we analyzed transcriptome expression patterns in glumous flower of cold-tolerant japonica rice variety, Stejaree45, and cold-susceptible variety, HR19621-AC6 at booting stage under cold water irrigation. A total of 2,411 probes were differentially expressed by low temperature in glumous flowers of the two varieties. Some important genes involved in hormone biosynthesis showed variety-specific regulation. Expression of GA20ox3 and GA2ox, among the genes involved in GA biosynthesis, was regulated differentially in the two varieties. Among the genes involved in IAA biosynthesis, YUCCA1 and TAA1:1 showed variety-specific regulation. Among the genes involved in cytokinin biosynthsis and signaling, expression of LOG, HK1 and HK3 was significantly down-regulated only in the cold-susceptible variety. Among the genes involved in ABA biosynthesis, NSY and AAO3 were down-regulated only in the cold-tolerant variety. In general, genes involved in GA, IAA and cytokinin biosynthesis responded to cold temperature in such a way that capacity of those bioactive hormones is maintained at relatively higher levels under cold temperature in the cold-tolerant variety, which can help minimize cold stress imposed to developing reproductive organs in the cold-tolerant variety.

콩의 PR10 유전자(GmPR10)를 벼에 형질전환하여 GmPR10 전이 유전자의 발현 정도와 내염성 관련 형질의 반응 사이의 인과관계를 조사하여 염 스트레스에 대한 GmPR10 생리적 기능을 분석하고 내염성 유전자원을 개발하였다. 1. 전이 유전자는 형질전환 계통에 따라 게놈 내에 1 ~ 6개의 사본이 도입되었고, 선발된 8개의 형질전환 계통 모두에서 전이 유전자가 발현되었으며, 발현 정도는 계통에 따라 변이를 보였다. 2. T1세대 2계통의 형질전환

Barley landraces harbor significantly higher genetic diversity than modern cultivars. Diversity of agronomic and morphological traits was investigated for 386 accessions of Korean landrace barley which were back-introduced from Okayama University, Japan. Among the accessions, 279 were covered barley and 89 naked barley. Seeds were sowed in late October and major growth characteristics were investigated at maturity and after harvest. The traits evaluated exhibited higher variation with respect to the CV, ranging from 47 to 60. The trait exhibiting the greatest variation was flag leaf width (FLW, CV=60 with 2.8x difference between minimum 0.6 and maximum 1.7). Those traits exhibiting least variation were heading date (HD, CV=47.2 with 31 days difference between the earliest and the latest) and seed number per spike (SNS, CV= 48.9 with 2.8x difference between minimum 36 and maximum 72). The other eight traits [maturity date (MD, CV= 53.7), culm length (CL, CV= 55.4), flag leaf length (FLL, CV= 51.6), spike length (SL, CV= 54.3), awn length (AL, CV= 54.4), whole spike length (WSL, CV= 52.9), spike density (SD, CV= 52.7), seed rows of spike (SRS, CV= 50.1)] were intermediate in their level of variation with respect to the CV. The first, second and third principal components explained about 30.3%, 17.0% and 13.4% of the total variation of the traits, respectively. The traits which contributed more positively to PC1 were SL, SD, WSL and AL. The traits which contributed more positively to PC2 were SRS and SNS, and those contributed more positively to PC3 were FLL and FLW. The Korean landrace barley accessions contain significantly diverse variation to explore for the improvement of agronomic and morphological traits of current elite cultivars. This work was supported by a grant from Regional Subgenebank Support Program of Rural Development Administration, Republic of Korea.

A resveratrol synthase (RS) gene was isolated from peanut (Arachis hypogaea, L. cv. Jinpoong) plants. This gene was placed under the control of the cauliflower mosaic virus 35S promoter (CaMV35S) and introduced into two Korean varieties of potato (Solanum tuberosum L. cvs. Jasim and Jowon) plants by Agrobacterium-mediated gene transfer. Putative transformants were screened by PCR with primers designed from CaMV 35S promoter, NOS terminator and RS gene. Most of selected transgenic potato plants showed the amplification of expected fragments by PCR of genomic DNA with gene-specific primers, while they were absent in untransformed control plants. Expression of the resveratrol synthase gene was also examined by northern blot analysis. The transformants showed a band which was lacking in the control plant, confirming that the introduced gene is transcribed into mRNA in the transformants. The strength of the band, which reflected the level of mRNA expression, differed among the individual transformants. Among the transformants obtained, the highest trans-resveratrol content in the transgenic young leaves of purple-fleshed "Jashim" was 2.11 μgg-1 fresh weight and that in the microtubers in vitro of purple fleshed "Jashim" was 8.31 μgg-1 fresh weight. This amount of resveratrol may have a positive biological effect on human health.