This experiment was conducted to investigate the changes of growth and maturity and to clarify the function of supernodulating characters, excessive nodules and high biological nitrogen fixation rate (BNF), on maturity in response to different planting time in supernodulating soybean mutants. Two supernodulating soybean mutants, Sakukei4 and SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2, were planted on May 24 and June 15, 2004. The degrees of the shortening of growth days by the planting time delay were 18 to 22 days in four cultivar, and there were no significant differences among the cultivars. However, four cultivars showed the different maturity properties. Sakukei4, mutated from Enrei, showed later maturity than that of Enrei, and 882-2, mutated from Shinpaldalkong2, showed earlier maturity than that of Shinpaldalkong2. The plant and nodule dry weights at R6 stage of Sakukei4 showed the smallest decrement and those of SS2-2 was showed the largest decrement by the delay of planting time. The photosynthetic rates of Sakukei4 during the late reproductive growth period were slowly decreased, however those of SS2-2 were steeply decreased in two planting time treatments. Overall, the growth of Sakukei4 was decreased slowly, however the growth of SS2-2 was decreased sharply according to the delay of planting time. The percentage of seed yield of Sakukei4 in June planting plot compared with May planting plot at R8 stage was 92~% , which was the lowest decreasing rate of yield among the cultivars, and in the case of SS2-2, it was in 76~% , the highest one. These results indicated that the responses of supernodulating mutants by the delay of planting time were very similar to the wild types. This means supernodulating characters in supernodulating soybean mutants might not affect to the maturity property. Additionally, the maturity property could be considered as an important characteristics to decide or to select on the developments of supernodulating soybean mutants, which have a low productivity by an excessive nodules, especially.

This experiment was conducted to clarify the functions of supernodulating characters on seed yield determination through the comparison of agricultural traits of supernodulating soybean mutants, Sakukei4, SS2-2, and their parent cultivars, Enrei and Shinpaldalkong2. The plant dry weights of supernodulating mutants, Sakukei4 and SS2-2, were 52~% and 61~% of their wild type parents at full seed stage (R6). However, the relative growth rate (RGR) from the pod set stage (R3) to R6 of Sakukei4 was 0.022 g/g/day and that of SS2-2 was 0.016 g/g/day, which were higher than those of their parents. Nodule number and dry weight were increased in two supernodulating mutants by the R6 stage. The nitrogen concentrations of leaf, petiole and stem of Sakukei4 were higher than those of Enrei. SS2-2 showed higher nitrogen concentration in petiole than Shinpaldalkong2 had. The positive correlations were appeared between nodule dry weight, plant dry weight and pod number, in two supernodulating mutants during the period from R3 to R6 stage. Although all of the yield components and seed yield were lower in two supernodulating mutants than their parents at the stage of full maturity (R8), the harvest index was higher in supernodulating mutants. The increasing rates of pod number to stem dry weight in two supernodulating mutants showed the higher than those of two their parents at R8 stage. In conclusion, the relative growth rates during the early to the middle reproductive growth period were higher in supernodulating mutants than the wild types. This could be resulted in an increase in pod number. The increase of relative growth rate was the result of the successive supplement of nitrogen source from biological nitrogen fixation (BNF) of nodules during the middle reproductive growth period in supernodulating mutants.

This experiment was conducted to investigate the soil nitrogen credit of biological nitrogen fixation (BNF) and the nitrogen balance of soybean in soybean-barley cropping systems. Soybean cultivar, Shinpaldalkong2 and barley cultivar, Olbori, were used in soybean mono-cropping (SM), barley monocropping (BM), and barley­soybean double cropping system. The barley-soybean double cropping system was treated with two different levels of nitrogen fertilizers, 0 nitrogen fertilizer (BS-F0), and standard nitrogen fertilizer (BS-F1). Nitrogen and organic matter concentrations in soil of BS-F1 plot on October, 2001 were increased 4.8~%~;and~;5.9~% , respectively, compared with those on October, 2000. The ranges of BNF rate in soybean were 69.1~~ 88.2~% in two years, and the rate was the highest in BS-F0 plot and the lowest in SM plot. The ranges of nitrogen harvest index (NHI) in all treatments were 83.9~~86.7~% . The yield was 270 kg/10a in BS­F1 plot and 215 kg/10a in BS-F0 plot. However, the nitrogen balances were +0.6 kg/10a of gain of soil nitrogen in BS-F0 plot and -0.4 kg/10a of loss of soil nitrogen in BS-F1 plot. In comparisons of SM and BS-F1 plots, although the seed yields were similar in two plots, the loss of soil nitrogen was higher in SM than BS-F1 plot. Overall, our results suggest that barley-soybean double cropping system was more effective in respect to seed productivity and soil nitrogen conservation than soybean monocropping system, and the N credit to following crops by soybean cultivation was identified in soybean double cropping system.

During the period of every summer to early autumn seasons, ships have been wrecked or grounded from effect of a typhoon in the water areas around Korean Peninsula Typhoon Rusa killed more than 100 people in September 2002. Super Typhoon Maemi passed southeast of South Korea in September 12-13, 2003, with a strong gale blowing at a record 60 m/s and caused much ship groundings, collisions and sinkings over 3000 in dockyards, harbors and places of refuge. These are things that could have been prevented had there merely been prior warning. This study outlines the occurrence characteristics of maritime accidents caused by a typhoon in South Korea for the period from 1962 to 2002. The distribution of the accident records is also compared with the trajectories, winds, central pressures of typhoons, passed during the 1990-2003. It is shown that attack frequency of typhoon and number of marine accidents is the highest in August and the marine accidents due to typhoon have a close relation to the distribution of accumulated wind and pressure fields.

To investigate low temperature- and light stress-induced genes of Hordeum vulgare L. cv. Dongbori #1, suppression subtractive hybridization (SSH) was performed with mRNAs from leaf samples that treated with low temperature (4℃) and extremely high light de

Cyanidin 3-glucoside (C3G) content contained in the grains of blackish purple rice varieties, Heugjinjubyeo, Kilimheugmi, Heugnambyeo, Sanghaehy-anghyeolla, and the progenies derived from their crosses was evaluated by HPLC and UV-Vis spectroscopy. C3G content was higher in the range of 10-30% by using UV-Vis method compared to HPLC method. A significant linear relationship was, however, observed between two analytical methods. The correlation coefficient was 0.98. Thus, this results suggested that it would be able to use UV-Vis spectroscopy to determine C3G content which does not demanded precise value like selection.

In cryopreserved rat embryos, survival rates obtained in vitro are not always consistent with the rates obtained in vivo. To determine the optimal conditions for in vivo development to term, rat embryos at the 4-cell, 8-cell and morula stages were vitrified in EFS40 by a 1-step method and transferred into oviducts or uterine horns of recipients at various times during pseudopregnancy. Vitrified and fresh 4-cell embryos only developed after transfer into oviducts of asynchronous recipients on Day -1 to -2 of synchrony, i.e., at a point in pseudopregnancy that was 1-2 days earlier than the embryos. However, although about half the vitrified embryos transferred into oviducts on Day -1 developed to term, only a minority of embryos transferred at later times did so, whether vitrified (10-34%) or fresh (24-33%), suggesting that this may not be the most suitable stage for cryopreservation. Very few 8-cell embryos, either vitrified or fresh, developed when transferred into oviducts on Day 0 to -0.5. However, when transferred into uterine horns, high proportions of vitrified 8-cell embryos (-63%) developed to term in reasonably synchronous recipients (Day 0 to -0.5) but not in more asynchronous ones (6%; Day-1). A majority of vitrified morulae also developed to term (52-68%) in a wider range of recipients (Day 0 to -1), the greatest success occurring with recipients on Day -0.5. Similar proportions of vitrified and fresh 4-cell embryos, 8-cell embryos and morulae developed to term when there was appropriate synchronization between embryo and recipient. Thus vitrification of preimplantation stage rat embryos does not appear to impair their developmental potential in vivo.

We have analyzed the genetic diversity of 45 squash genotypes in Cucurbita maxima, C. moschata, C. pepo and uniden-tified Cucurbita spp. (noodle-squash) with molecular markers. The 45 squash accesions showed molecular variations of 87.5% inRAPD and 74.4%