Photoperiod sensitive genetic male sterile (PGMS) rice is sterile mutant controlled by photoperiod. A PGMS mutant 920S was sterile grown under long-day (LD) photoperiod (14 h light/10 h dark) but fertile grown under short-day (SD) photoperiod (10 h light/14 h dark). Proteome analysis revealed that 12 protein spots were differentially expressed in the spikelets of 920S plants either treated with LD or SD photoperiod. Among these proteins, three proteins including chlorophyll a/b binding protein, vacuolar ATPase β-subunit,~;α-tubulin and an unknown protein were more than three-fold abundant in the spikelet of the SD-treated plants than those of the LD-treated plants. On the other hand, eight proteins including acetyl transferase, 2, 3- biphosphoglycerate, aminopeptidase N, pyruvate decarboxylase, 60S acidic ribosomal protein and three unknown protein spots were more abundant in the spikelets of the LD-treated plants than those of the SD-treated plants. The results suggest that the observed proteins may be involved in sterile or fertile pollen development under LD or SD photoperiod respectively in the PGMS mutant rice.

Cheonsu is a new japonica rice cultivar tolerant to drought. This cultivar was developed from the cross Ilmibyeo// Juanbyeo/Salshare, where the parent Ilmibyeo is a japonica cultivar with high eating quality, Juanbyeo is a japonica for direct-seeding cultivation, and Salshare is a japonica weedy rice from Korea. The preliminary and replicated yield trail on Cheonsu was carried out at Yeungnam University in 2001, 2002 and 2003, and the local adaptability test was carried out by the National Seed Management Office (NSMO), Korea, in 2004 and 2005. This cultivar was registered to NSMO, Korea, as variety Cheonsu in 2006. Cheonsu has about 122 days growth duration from transplanting to harvesting. This cultivar has stature with 81cm of culm length. The milled rice yield of Cheonsu is about 5.10 MT/ha under standard fertilizer level of the ordinary transplanting cultivation. Amylose content of this cultivar is 18.3%.

Sanho is a new japonica rice cultivar with brown pericarp color (Fig. 1). This cultivar was developed from the cross Ilmibyeo//Ilmibyeo/Pyeongtaekaengmi 4, where the recurrent parent Ilmibyeo is a japonica cultivar with high eating quality, and the donor

Phenotypes of panicle, hull and seed of mutant rice (Oryza sativa L.) were characterized. Panicle mutants were classified in 4 groups with their internode length of main rachis, primary rachis, secondary rachis and pedicel. Hull and seed mutants were grouped into 12 based on their mutant characters in shape, size and color of seeds. These natural and spontaneous mutant collections showed distinct phenotypes to wild type rice. This might be useful for the identification of the functions of genetic factors in the Mendelian inheritance.

Photoperiod sensitive genetic male sterile (PGMS) rice 920S was characterized as sterile when it was grown under longday condition but fertile when grown under short day condition. PGMS rice 920S, Fl and F2 plants were examined for their fer-tilities unde

Molecular markers were used to map and characterize quantitative trait loci (QTLs) for traits related to cold tolerance in an intrasubspecif ic backcross population of r ice. The parents of the cross were a cold susceptible Tongil-type cultivar 'Milyang23

In order to know the phylogenetic relationships between wild, weedy and cultivated rice, half diallel crosses among nine accessions including a wild rice Oryza rufipogon W130, three long grain weedy rices Cheongdoaengmi 1 from Korea, C9575 from Japan, BT5