The purpose of this study was to select some superior soybean varieties adaptable to growth in the northern parts of the Korean peninsula, and to identify the suitable growing regions of soybean in North Korea. Soybean varieties from South Korea were evaluated with the Chinese locally cultivated varieties as check varieties at two locations, Donggang City of Lianing Province, and at Longjing City of Jilin Province, 2017-2019. A total of 100 soybean varieties from South Korea and three Chinese check varieties were evaluated based on ecological adaptability, and a total of 18 varieties including ‘Suwon 212’ from the Longjing test site as well as a total of 59 genotypes the Donggang test site, were selected for further evaluation in the first experiment year. A total of 12 promising soybean varieties at Longjing and 15 varieties at Donggang that were selected from the previous year, were evaluated at the same sites for ecological adaptability as well as productivity in the second experiment year. A total of nine promising soybean varieties were selected at the test sites, respectively. The nine varieties at each site that were selected from the previous year for the production capacity including flowering date, degree of lodging, yield potential, and disease resistance, were reviewed to evaluate at both sites in the last experiment year. Finally, a total of eight superior varieties, including four at the Longjing site (‘Seonnogkong’, ‘Dajinputkong’, ‘Danweonkong’ and ‘Sinpaldalkong 2’) and the other four at the Donggang site (‘Iksan 13’, ‘Seonnogkong’, ‘Gangil’ and ‘Yeonpung’) were selected. The yield potential of four outstanding soybean varieties selected at the Longjin site was 1.5-2.6t/ha, and that of the other four at the Donggang site was 2.1-2.7t/ha.

Rice flour is used in many food products. However, dough made from rice lacks extensibility and elasticity, whereas that of wheat is suitable for many food products including breads. We have produced marker-free transgenic rice plants containing a wheat TaGlu-Ax1 gene encoding the HMG-GS from the Korean wheat cultivar ‘Jokyeong’ using the Agrobacteriummediated co-transformation method. The TaGlu-Bx7-own promoter was inserted into a binary vector for seed-specific expression of the TaGlu-Ax1 gene. Two expression cassettes comprised of separate DNA fragments containing only TaGlu-Ax1 and hygromycin phosphotransferase II (HPTII) resistance genes were introduced separately to the Agrobacterium tumefaciens EHA105 strain for co-infection. Each EHA105 strain harboring TaGlu-Ax1 or HPTII was infected to rice calli at a 3:1 ratio of TaGlu-Ax1 and HPTII, respectively. Then, among 210 hygromycin-resistant T0 plants, we obtained 20 transgenic lines with both TaGlu-Ax1 and HPTII genes inserted into the rice genome. We reconfirmed integration of the TaGlu-Ax1 gene into the rice genome by Southern blot analysis. Transcripts and proteins of the wheat TaGlu-Ax1 were stably expressed in the rice T1 seeds. Finally, the marker-free plants harboring only the TaGlu-Ax1 gene were successfully screened at the T1 generation.

Superoxide dismutases (SOD) are metalloenzymes that convert O2- to H2O2. Rehmannia glutinosa is highly tolerant to paraquat-induced oxidative stress. The primary objective of this study was to characterize regulation of SOD gene expression in R. glutinosa in response to oxidative stresses and hormones. A full-length putative SOD clone (RgCu-ZnSOD1) was isolated from the leaf cDNA library of R. glutinosa using an expressed sequence tag clone as a probe. RgCu-ZnSOD1 cDNA is 777 bp in length and contains an open reading frame for a polypeptide consisted of 152 amino acid residues. The deduced amino acid sequence of the clone shows highest sequence similarity to the cytosolic Cu-ZnSODs. The two to three major bands with several minor ones on the Southern blots indicate that RgCu-ZnSOD1 is a member of a small multi-gene family. RgCuZnSOD1 mRNA was constitutively expressed in the leaf, flower and root. The expression of RgCu-ZnSOD1 mRNA was increased about 20% by wounding and paraquat, but decreased over 50% by ethylene and GA3. This result indicates that the RgCu-ZnSOD1 expression is regulated differentially by different stresses and phytohormones at the transcription level. The RgCu-ZnSOD1 sequence and information on its regulation will be useful in investigating the role of SOD in the paraquat tolerance of R. glutinosa.

Thirty-nine out of eighty-five barley varieties/strains survived until heading stage in the saline experimental field (0.03-0.05~%~;salt) and they were used for pollen study. Light and scanning electron microscopic observations revealed two distinctive types of barley pollens: one transparent and small in size and the other dark and larger. In addition, both types of pollens were stained with Alexander's stain and it was found that the smaller and transparent pollen was cytoplasm-devoid (CD) while the larger pollen was cytoplasm-rich (CR). Sixteen out of 39 barley varieties/lines grown in the saline soil had CR pollens, which were rarely observed in the barley plants grown in the non-saline soil. Moreover, it was observed that salt stress severely reduced seed setting in the varieties having degenerated pollens. These results suggest that salt stress affects the fertility of barley pollen. The sterile pollen was undersized and lack of cytoplasm probably due to abortion. Furthermore, a varietal difference existed in the response of pollen development to salt stress.