Asian cultivated rice was domesticated from ihe wild rice, Oryza rufi/iDgon and throughout the domesiiealion process, a wide range of morphological and physiological changes altered the ancestral form. This study was conducted lo idenlify the genetic basis of changes associiiied wilh the domestication process. An recombinanl Inbred line (RIL) population consisting of 120 lines w:is developed from a cross bciwccn ihc inpouica cultivar. 'Hwayeongbyeo' and a presumed wild progenitor. O. riijipof^on Griff. Acc.01944. The population was genotyped with 124 simple sequence length repeat (SSR) markers, providing an average interval size of 15 cM. and also evaluated for 20 [rails related to domestication and agricultural performance. A total of 63 quantitative (rail locus (QTLs) and one locus associated with qualitative variation for pericarp coloration were identified using single poini and composite interval analysis. The number of QTLs per trait ranged from one lo seven. Phenoiypic variation associated with each QTL ranged from ?.! to 40.4%. with an average of 15.3%. The results indicated thai most domestication-related traits clustered in chromosomal blocks, and the positions of many of ihese clusters were consistent with those reported in previous studies and with skewed segregation ratios in ihese BCjFv RILs. For LI (20.6%) ofthe QTLs identified in this study, the O. rufipogoii-denved allele contributed a desirabie agronomic effect despite the overall undesirable characteristics of the wild phenotype. Favourable alleles from O. rtifipogoii were detected for panicle length, spikelets per panicle, days to heading and leaf discoloration associated with cold stress. When compared with previous studies involving interspecific crosses, it can be concluded that O. riifipogon is useful as a source of valuable alleles for rice improvement and that many of the introgressed regions contain genes that have a favourable impact on phenotype in different genetic backgrounds and different environments.

Abstract. We investigate the electron temperature of the inner halo and nebular core regions of NGC 6543, using archival Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2) images taken through narrow band [O iii] filters. Balick et al. (2001) showed that the inner halo consists of a number of spherical shells. We find the temperature of this inner halo to be much higher (∼15 000 K) than that of the bright core nebula (∼8500 K). Photo-ionization models indicate that hardening of the UV radiation from the central star cannot be the main source of the higher temperature in the halo region. Using a radiation hydrodynamic simulation, we show that mass loss and velocity variations in the AGB wind can explain the observed shells, as well as the higher electron temperature.