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Rice (Oryza sativa L.) can produce black grains as well as white. In black rice, the pericarp of the grain accumulates anthocyanin, which has antioxidant activity and is beneficial to human health. We developed a black rice introgression line in the genetic background of Oryza sativa L. ‘Koshihikari’, which is a leading variety in Japan. We used Oryza sativa L. ‘Hong Xie Nuo’ as the donor parent and backcrossed with ‘Koshihikari’ four times, resulting in a near isogenic line (NIL) for black grains. A whole genome survey of the introgression line using DNA markers suggested that three regions, on chromosomes 1, 3 and 4 are associated with black pigmentation. The locus on chromosome 3 has not been identified previously. A mapping analysis with 546 F2 plants derived from a cross between the black rice NIL and ‘Koshihikari’ was evaluated. The results indicated that all three loci are essential for black pigmentation. We named these loci Kala1, Kala3 and Kala4. The black rice NIL was evaluated for eating quality and general agronomic traits. The eating quality was greatly superior to that of ‘Okunomurasaki’, an existing black rice variety. The isogenicity of the black rice NIL to ‘Koshihikari’ was very high.

Characterization of resistance genes is essential for the development of a new variety resistant to blast (Magnaporthe grisea) in rice (Oryza sativa L.). In this study, we found that an indica variety, Kasalath, harbored a resistance gene that showed a broad spectrum of resistance reactions against standard differential blast isolates from the Philippines and Japan. Quantitative trait locus (QTL) analysis was conducted using backcross inbred lines derived from crosses between Kasalath and the japonica cultivar, Koshihikari, to detect the QTL for blast resistance. QTLs were detected on chromosomes 6 and 8. Further, QTL analysis of chromosome segment substitution lines of Kasalath in the Koshihikari genetic background revealed that the Kasalath allele at the QTL on chromosome 6 strongly contributed to blast resistance. These results suggested that the gene locus might be identical to Pi13(t) that had already been reported. By marker-assisted breeding, a near-isogenic line, Koshihikari Toyama BL7, with a Kasalath chromosome segment containing Pi13(t) introduced into Koshihikari genetic background, was developed. The reaction of Koshihikari Toyama BL7 to the differential blast isolates indicated that Pi13(t) was a broad-spectrum and moderate resistance gene. Since Pi13(t) showed single-gene segregation and was characterized, the gene was re-designated as Pi13.

The visible absorption spectra for [Co(hmpa)4](ClO4)2-L-nitromethane systems (L = H2O, MeOH, EtOH, n-PrOH, i-PrOH, n-BuOH, FA, NMF, DMF, DEF, DMA, DEA or DMSO) have been studied. The results indicate that the configurational inter- conversions from the tetrahedral [Co(hmpa)4]2+ to the octahedral [Co(hmpa)2L4]2+ accompanying the ligand substitution reactions occur in nitromethane, except for the DMA and DEA systems. The values of both ΔH and ΔS for the interconversions increase in the following order: H2O

Tetrahedral [Co(hmpa)4]2+ ion undergoes a single step reaction with L (L=FA, NMF, DMF, DEF, or DMSO) to form an octahedral [Co(hmpa)2L4]2+ ion in nitromethane. The temperature dependences of the equilibrium constants of tetrahedral-octahedral configurational interconversions exhibit similar values of ΔH=−30–−33 kJ mol−1 and ΔS=−115–−149 J mol−1 K−1 respectively except for larger values for the DMSO complex.

Four analogues of vitamin D3 with an oxygen atom in the side chain skeleton were synthesized to determine whether their differentiation-inducing activity could be separated structurally from their activity to induce hypercalcemia. The order of the in vitro potency to reduce nitroblue tetrazolium in human myeloid leukemia cells (HL-60) was 22-oxa-1 alpha, 25-(OH)2D3 greater than 1 alpha, 25-(OH)2D3 greater than 20-oxa-1 alpha, 25-(OH)2D3 not equal to 22-oxa-1 alpha-(OH)D3 greater than 1 alpha-(OH)D3 greater than 20-oxa-1 alpha-(OH)D3. 22-Oxa-1 alpha, 25-(OH)2D3 was also about 10-times more potent than 1 alpha, 25-(OH)2D3 in suppressing proliferation and inducing differentiation of mouse myelomonocytic leukemia cells (WEHI-3), but the former was much weaker than the latter in inducing the release of 45Ca from prelabeled fetal mouse calvaria. These results suggest that the differentiation-inducing activity of vitamin D compounds can be separated structurally from their activity to induce hypercalcemia.