Korea has experienced a rapid warming of 1.5℃during the last 100 years and even faster rise of air temperature is being projected in the future. This experiment was done to figure out the impact of the predidted temperature rise on the growth and yield of rice. Two rice varieties, "Hwaseongbyeo" and "Dasanbyeo" were grown in 1/5000a Wagner pot under the four plastic houses that were controlled to ambient, ambient+1.5℃, ambient+3℃ and ambient+5℃ throughout the rice growing season. Heading dates in the elevated temperature treatments were three to five days earlier than in the ambient temperature treatment. Rice growth was affected by temperature treatments differentially according to the tested cultivars. Hwaseongbyeo(japonica) showed significant reduction of shoot dry weight under ambient+5.0℃ treatment compared to the other treatments, while Dasanbyeo(tongil-type) showed significant increase of shoot and root dry weight under the elevated temperature treatments. The number of panicles per pot and spikelets per panicle and per pot was not significantly different among temperature treatments in both cultivars tested, but significantly lower grain yield was observed under the treatments raising the air temperature to the level of 3.0℃ and 5.0℃ above the ambient air temperature. This lower grain yield in the elevated temperature treatment of ambient+3℃ was attributed mainly to the decrease of grain weight due to the shortening of grain filling period, while the drastic yield reduction in the treatment of ambient+5℃ was caused not only by the lower grain weight but also by the marked increase in spikelet sterility due to the high temperature at meiotic and flowering stage. In conclusion, the ongoing global warming is expected to decrease the grain yield not only by decreasing the grain filling period in the near future but also increasing the spikelet sterility under the long-term projected climate of Korea.

This experiment was conducted to evaluate the effect of temperature rise on the phenological development and yield of oilseed rape in temperature-controlled plastic houses located at Suwon in 2008 and 2009. Two varieties "Halla" and "Naehan" were grown using 1/5000a Wagner pots in the three plastic houses greenhouses in which temperature was controlled to ambient temperature (AT), AT+1.5℃, and AT+3.0 through the growing season. Compared to the ambient temperature, leaf appearance was speeded up by temperature elevation, resulting in earlier flowering by 7 and 19 days at the treatments of AT+1.5℃and AT+3.0℃, respectively. YGrain yield was decreased by approximately 15% for each temperature elevation of 1.5 ℃. The yield decrease was attributed to the increased sterility and the decreased grain weight under the higher temperature conditio

Temperature rise of 4.0℃ is projected under SRES A1B greenhouse gases emission scenario in 2100 and this climate change is anticipated to affect the growth, phenological development, and yield of soybean. The objective of this experiment is to calibrate and validate CROPGRO_soybean model and evaluate the projected climatic change impact on soybean phenological development in Korea. For simulation experiment, four cultivars with different maturity groups, Hwaeomputkong(MG1), Sinpaldalkong(MG4), Taegwangkong(MG5), and Daewonkong(MG6) were calibrated and validated using data that were collected from the experiments of planting dates and daylength treatment. The calibrated model predicted the phenological stages with considerable accuracy for the data acquired independently of the calibration data. As global warming proceeds, days to flowering and days to physiological maturity on average across varietal groups and planting dates are anticipated to decrease by about 7 and 5 days respectively under the projected normal climate during the period of 2071~2100 compared to those under the current normal climate condition.

In order to investigate the genotypic differences in Pb accumulation of rice, thirty-five rice cultivars were irrigated by irrigation water containing 10 ppm Pb throughout all growth season under field condition. At harvest, thirty-five rice cultivars showed significant difference in Pb concentrations in straw, grain, chaff, brown rice, rice bran, and polished rice, but not in root. Pb concentration in polished rice ranged from 0.02 to 0.22 mg/kg. The total Pb accumulation in shoot varied from 0.77 to 2.74 mg/m2. There were no significant difference of Pb concentration in all of rice parts among four rice cultivar groups. Indica and tongil cultivar groups presented the higher Pb accumulation in shoot. The large genotypic variation suggested the possibility of breeding low Pb accumulating rice cultivar.

Cd contamination in irrigation water can imperil human health through food chain. In order to investigate the genotypic differences in Cd accumulation of rice, thirty-five rice cultivars of different cultivar groups (temperate japonica, tropical japonica, tongil, and indica) were grown with irrigation water containing 2 ppm Cd throughout all growing season under the field condition in 2007. At harvest, highly significant differences in Cd concentration in different rice parts (root, shoot, straw, grain, chaff, brown rice, rice bran, and polished rice) was found among rice varieties and rice cultivar groups. Cd concentration of polished rice ranged from 0.26 to 1.85 mg/kg. The total Cd accumulation of shoot varied from 0.69 to 7.87 mg/m2. Indica cultivar group showed significantly higher Cd concentration and accumulation compared to the other rice cultivar groups. On the other hand, the distribution ratio in polished rice was the highest in Tongil cultivar group. The large genotypic variation suggested the possibility of breeding low Cd accumulating rice variety.

Leaf color can be used as an indicator of the plant healthiness, and thus digital image analysis may provide farmers and researchers with time- and resource-saving methods for diagnosing plant nutrient status. The digital images are dependent on the ambient light, therefore the color indices of digital images should be compensated for the difference of ambient light. The objectives of this study were to develope the calibration methods for color indices under variable irradiance condition. Four color panels were used for RGB (Red, Green, Blue) values and color indices calibration purpose. Reflectance for each panel was measured by spectro-radiometer with a waveband range of 300 - 1100 nm. The reflectance values of four color panels was used as a reference for calibration of RGB values and color indices. Using digital camera color images were taken for rice canopies together with reference panel that was set up at the level of canopy surface. Digital images were obtained form rice fields with variable nitrogen fertilization managements at active tillering to panicle initiation stage. The calibration coefficients for color image indices were calculated by using the linear regression equation between the pixel values of color image for reference panel and their known reflectance values. The determination coefficients (r2) of linear regression between non-calibrated mean B values of plant pixels in color image and shoot nitrogen contents in four rice varieties, Odae, Hwasung, Chucheong, and Ilpum, was 0.30, 0.27, 0.37, and 0.27, respectively, while the respective r2 values were increased to 0.79, 0.85, 0.77, and 0.53.by applying the calibration coefficient. These results imply that color digital image analysis could be a promising method for diagnosing nitrogen nutrition status of rice canopy.

Korea has experienced a rapid warming of 1.5℃ during the last 100 years and it is projected more faster rise of air temperature in the future. Temperature is an important factor that impacts directly on the growth and development of plants. To figure out the impact of temperature rising on rice growth, grain yield, and quality, an experiment was conducted at the 3 plastic houses that were controlled to ambient, ambient+1.5℃, and ambient+3℃throughout the growing season at the Seoul National University Experimental Farm. A rice variety "Hwaseongbyeo“ was grown using 1/5000a Wagner pot under two nitrogen levels of 12 and 18kg/10a. Heading date in elevated temperature treatments was earlier by two days than in ambient temperature. Compared to the ambient temperature, number of tiller, leaf area index, and dry weight of root, stem, leaf, and panicle was greater in elevated temperature conditions throughout the rice growing season, the difference being smaller in later grain filling period. There was no interaction effect on growth between nitrogen levels and temperature treatments. Grain yield and grain quality are under measurements.

Although there can be some differences among varieties, the developmental rate of soybean (Glycine max) is mainly influenced by temperature and photoperiod. The objective of this experiment, that is the first step for creating phenology model of soybean, is to investigate the developmental characteristics under different temperature and day length conditions. Considering maturity, employed were five cultivars, Hwaeomputkong, Sinpaldalkong, Taegwangkong, Daewonkong, and Seoritae. They were sown at three different dates and grown under natural day length throughout growing season in 2008, while in another field they were subjected to longday of 16 hours by the supplemental lighting from July 6 to maturity. Developmental processes were investigated every five days after seeding. Days to flowering and final number of node increased in late maturiity cultivars. These traits decreased in delayed seeding, while increased under longday treatment. Even though there were some varietal differences in the slope of the line, V-stage(the number of nodes) of soybean consistently showed the linear relation(r2>0.95) with the sum of effective temperature from emergence to flowering. Daylength would be a cardinal factor that determines development including final number of node and duration of reproductive stage. However, it has not been figured out completely. Further studies will focus on the effect of temperature on reproductive stage and developmental response to daylength.