This study was done to understand the G x E interaction of rice blast reaction for Japonica high quality rice varieties and to observe blast pattern for high quality varieties. Twenty one percent of the total sum of squares (SST) in blast reaction data of high quality Japonica varieties is attributed to genotype (G) by environment (E) interaction variation. This portion of blast response is higher than 8～12% of G x E effect in blast severity data obtained from various ecotypes of rice varieties. Blast response scores obtained from high quality Japonica varieties group were more severely affected by environment condition than mixed groups with Japonica and Indica varieties. Interaction Principal Component Analysis (IPCA) scores obtained from AMMI analysis for the leaf blast response implied variation of G x E interaction. Correlation analysis suggested that IPCA1 was associated with latitude, maximum mean temperature, precipitation and mean cloud amount. IPCA2 was associated with mean relative humidity, and IPCA3 was associated with precipitation and minimum relative humidity. Pattern analysis generated nine genotype clusters according to blast reaction over 11 regions. Collectively, the A, B, C, and D groups were susceptible to rice blast, where as the E, F, G, H, and I groups were relatively resistant to rice blast through multi-location blast nursery test. Relationship between the identified genes of high quality varieties and blast scores at each test site in the level of group could be analyzed based on the results from G x E Interaction analysis.

Nitrogen (N) fertilization is essential for alleviating nutrient deficiencies of the world’s population by increasing rice production, one of the most important food crops of our time. Here we established an in vivo hydroponics rice seedling culture system to investigate the physio-biochemical and molecular responses of various rice genotypes to low nitrogen application. Yoshida’s nutrient solution (YS) was used to grow rice seedlings, and at three-week-old the seedlings manifested highly stable and reproducible symptoms, such as reduced shoot growth and length. Out of 12 genetically selected or tested genotypes, almost all (11 genotypes) showed varied degrees of growth reduction response to applied nitrogen (4 and 40 ppm N for treatment and control, respectively), but SR19663-B-B-34-3-3-3-1 showed similar growth as the control though its leaf width was smaller than the control. The leaves of a 11 representative low nitrogen-responsive genotype as BG90-2 were sampled for revealing the protein profiles between low and normal (control) nitrogen application by using two-dimensional gel electrophoresis (2-DGE) followed by staining of separated proteins with silver. Fifty differentially expressed silver stained protein spots were excised from 2-D gels and 41 proteins identified using high-throughput mass spectrometry (MS) using matrix-assisted laser desorption/ionization-time of flight-MS and nano electrospray ionization liquid chromatography tandem MS. These proteins could be assigned as major (energy metabolism, photosynthesis and oxidative stress) and minor functional categories, revealing many novel low N-responsive proteins, including those having energy/photosynthesis, and defense/stress, and iron homeostasis-related functions.

A population ofrecombinant inbred lines derived from a cross between Ilpumbyeo, a blast-susceptibleyopowca cultivarofhigh eating-quality and high yield potential, and GL33, a blast-resistance/apowca weedy rice was used to identifv QTLs affect-ing importan

This experiment was conducted to investigate the variation of nitrogen(N) uptake efficiency and their relationships withciency and partitioning parameters as physiological N use efficiency [PNUE], agronomic N use efficiency [ANUE], apparentrecovery [AR],

A recombinant inbred lines (RILs) consisting of 231 lines, derived from a japonica (Suweon365) and a japonica (Chu-cheongbyeo) rice, was used to investigate the genetic factors affecting cooking and eating quality of rice. Alkali digestion valueloci (QTLs