It has been reported that bacterial diseases of domestic soybean are bacterial pustule, wildfire, bacterial blight and bacterial brown spot. Among these bacterial diseases, bacterial blight infected by Gram-negative Xanthomonas campestris pv. glycines had been the most issue in soybean diseases. In recently, issue in soybean disease was shifted to wildfire by Gram-negative Pseudomonas syringae pv. tabaci. When infected in nature, symptom of wildfire generally surrounded infected-area of bacterial blight and formed pustule in infective center. Because optimum growth temperature of Wildfire is lower than these of bacterial pustule, Wildfire caused damage to crop yield in later growth stage. In this study, we checked symptoms of bacterial diseases with growth stages of soybean. Also, we surveyed disease severity of single infection, simultaneous infection and sequential infection of bacterial pustule and wildfire.

For the development of SSR marker system in Vicia villosa Roth, an enriched library was constructed by using a modified biotin-streptavidin capture method and the selected clones were sequenced with GS-FLX(454). Of 37,794 sequenced reads, we found that 8,474 reads (22.4%) were redundant, leaving 29,320 unique ones (77.6%). Among the unique clones, 17,174 reads (58.6%) were having microsatellite repeating motifs. Sequence analysis of all SSR-containing reads revealed a predominance of the di-nucleotide SSRs (62.5%). The tri-nucleotide and the tetra-nucleotide SSRs were 5.7% and 22.5%, respectively. As the di-nucleotide type, the AG/GA class of repeat motif was most frequently identified (55.0% of the total di-nucleotide SSRs), followed by the CT/TC class (19.5%), and the TA/AT class (12.1%). Among the tri-nucleotide SSRs, the AGT/GTA/TAG class of repeat motifs was predominant (22.2%), followed by the ACT/CTA/TAC class (17.8%). Among the tetra-nucleotide SSRs, the CTTT/TTTC/TTCT/TCTT class of repeat motifs was predominant (31.2%), followed by the AAAG/AAGA/AGAA/ GAAA class (19.9%). Finally, we designed 779 primer pairs from the flanking sequences of SSR containing reads. We are undertaking the analysis of polymorphisms using the diverse collected accessions of Vicia villosa Roth now. This newly developed SSR marker set shall provide a very useful tool for implementing molecular diversity assessment and population structure studies of Vicia villosa Roth onward.

The cultivation of green manure crop is considered as a good management practice by increasing soil organic matter and fertility levels. This experiment was conducted to improve the soil environment under rice-based cropping system at paddy soil (fine loamy, mixed, nonacid, mesic, family of Aeric Fluventic Haplaquepts) in National Institute of Crop Science (NICS), Korea in 2006 to 2007. The variation of soil temperature in green manure plots was lower than without green manure (control) during spring season (April to May). The temperature variation of no tillage plot (broadcast before rice harvest) was the lowest among treatments. After green manure cropping, the soil bulk density and porosity ratio were improved at the top soil. The production of green manure was the highest athairy vetch and barley mixture plot by partial tillage. However, mixture treatment had no improvement on soil organic matter. After rice cropping with green manure application, soil quality was improved such as soil physical properties except mixture treatment. Therefore, we suggest that soil quality should be improved by green manure cultivation under rice-based cropping system.

To facilitate an active breeding strategy for rice quality improvement, mutation were induced by treating rice variety Sindongjin seeds with gamma ray(300 Gray) and its fertilized eggs with MNU(1mM). Endosperm and grain shape of mutants were classified and selected in M2 population. From M2 generation, 48(7.6%) endosperm mutants and 179(11.9%) grain shape mutants were selected. White belly and White core were the most frequent. Selected grain mutants were classified into 16 types according to their morphological phenotypes. The overall segregation ratio was 3 : 1, controlled by one gene. Specially, SM-17 and SM-20 displayed segregation ratio of 9 : 7 and 1 : 15 respectively. Grain mutants showed generally earlier heading dates, shorter culm length and ear length than the parent. Grain length, grain width, and 1,000 grain weight were also mostly shorter and lower than the parent. In SEM analysis, each mutant type showed unique starch particle size and starch accumulation pattern. The density of polygonal cells and small inner corpuscles depending on amylose content decreased as following order - Waxy>Dull>Parent >White core. In SDS-PAGE analysis, SM-22 of Opaque group and SM-34 of Giant embryo group showed high glutelin polypeptide concentration. SM-23 of Floury group, SM-26 of Shrunken group, and SM-31 of Sugary group showed low concentration of total protein with variations in bands over 55kDa.

The cluster analysis of diurnal precipitation patterns is performed by using daily precipitation of 59 stations in South Korea from 1973 to 1996 in four seasons of each year. Four seasons are shifted forward by 15 days compared to the general ones. Number of clusters are 15 in winter, 16 in spring and autumn, and 26 in summer, respectively. One of the classes is the totally dry day in each season, indicating that precipitation is never observed at any station. This is treated separately in this study. Distribution of the days among the clusters is rather uneven with rather low area-mean precipitation occurring most frequently. These 4 (seasons) × 2 (wet and dry days) classes represent more than the half (59 %) of all days of the year. On the other hand, even the smallest seasonal clusters show at least 5∼9 members in the 24 years (1973-1996) period of classification. The cluster analysis is directly performed for the major 5∼8 non-correlated coefficients of the diurnal precipitation patterns obtained by factor analysis In order to consider the spatial correlation. More specifically, hierarchical clustering based on Euclidean distance and Ward's method of agglomeration is applied. The relative variance explained by the clustering is as high as average (63%) with better capability in spring (66%) and winter (69 %), but lower than average in autumn (60%) and summer (59%). Through applying weighted relative variances, i.e. dividing the squared deviations by the cluster averages, we obtain even better values, i.e 78 % in average, compared to the same index without clustering. This means that the highest variance remains in the clusters with more precipitation. Besides all statistics necessary for the validation of the final classification, 4 cluster centers are mapped for each season to illustrate the range of typical extremities, paired according to their area mean precipitation or negative pattern correlation. Possible alternatives of the performed classification and reasons for their rejection are also discussed with inclusion of a wide spectrum of recommended applications.

Sea water samples collected in August, 1994 from 20 stations in the Kwangyang Bay were analyzed by gas chromatography/mass spectrometry-selected ion monitoring (GC/MS-SIM) to investigate persistence and distribution pattern of four organophosphorus pesticides (DDVP, Diazinon, IBP, EDDP). Except for IBP, the contamination by DDVP, Diazinon, and EDDP in marine aquatic environment in Korea has not been reported previously. In this study, however, all these four pesticides were detected in all stations (except DDVP) and their concentrations were in ng/L level. The concentrations ranged from detection limit to 15.3ng/L for DDVP, 1.8-27.7ng/L for Diazinon, 7.3-63.5ng/L for IBP, and 22.2-1100.1ng/L for EDDP. It is noteworthy that the measured concentrations of IBP and EDDP in this study would be much lower than usual, since the use of IBP and EDDP was less than 50% of average annual consumption due to unusually dry and hot weather condition in the summer of 1994. It was very surprising to find that the highest concentrations of organophosphorus pesticides were observed at stations near Daesa Streamlet instead of Seomjin River, which has more point source of the pesticides. This result suggests that the small river discharge during heavy rain period in summer can give harmful effect on marine biota (both wild and aqua-cultured) with its organophosphorus pesticide residue, despite of their short residence time in aquatic environment. In order to protect the marine life properly from acute toxicity of the organophosphorus pesticides, it needs to be emphasized that monitoring the level of agricultural pesticides in river run-off should be done during active consumption period rather at regular intervals.