Chromosomal Location of HCA1 and HCA2, Hybrid Chlorosis Genes in Rice

Many postzygotic reproductive barrier forms have been reported in plants: hybrid weakness, hybrid necrosis, and hybrid chlorosis. In this study, linkage analysis of the genes causing hybrid chlorosis in F2 generation in rice, HCA1 and HCA2, was performed. HCA1 and HCA2 are located respectively on the distal regions of the short arms of chromosomes 12 and 11. These regions are known to be highly conserved as a duplicated chromosomal segment. The molecular mechanism causing F2 chlorosis deduced from the location of the two genes was discussed. The possibility of the introgression of the chromosomal segments encompassing HCA1 and/or HCA2 was also discussed from the viewpoint of Indica-Japonica differentiation

Nature of the Karakawa moor, Iwami-cho, Tottori Prefecture : topography, geology and vegetation

The Karakawa moor situated in the mountainous area of eastern part of Tottori Prefecture west Japan was investigated geologically and vegetationaty as the basic study for conservation of natural environments. The 26 hand orger drillings revealed the buried topography under the moor. There are small ridge and two shallow valleys under the moor. The formation of moor was promoted by deposition of dam upped sediments at the junction of these two valleys, The sediments are composed of gravel, silt and clay, volcanic ash and black organic soil (peat) in ascending order. The volcanic ash is considered as secondary deposits and identified as mixture of Aira Tn ash (ca.25ka) and Daisen Uh ash (ca.20 ± α ka) by means of thermomagnetic and also EDX analyses. From the results of fossil pollen analysis, the black organic soil is divided into three pollen zones in ascending order as follows; A zone (145-130 cm depth: Castanea & Castanopsis, Taxodiaceae &Cupressaceae, Betula, Cryptomeria), B zone (130-90 cm depth: Castanea & Castanopsis, Taxodiaceae & Cupressaceae, Cyclobalanopsis, Aesculus), C zone (90-35 cm depth: Taxodiaceae & Cupressaceae, Castanea & Castanopsis, Aesculus, Tsuga). the vegetation of the moor was inbestigated phytosociologically in 1980-1981 and 1988-1989. As the result of the studies, 5 communities were recognized. The following 3 communities with 2 sub-communities as a typical moor vegetation among them were discussed with the comparison of a secular change. 1) Eriocaulon miquelianum - Rhyncospora fauriei community 2) Hosta montana - Arundinella hirta community 　(2-1) Rhynchospora fauriei - A.hirta sub-community 　(2-2) Carex dispalata - A.hirta sub-community 3) Lythrum anceps - C.dispalata community (1) is an oligotrophic community favored by pudding water flowing from percolating underground water. (3) is an eutrophic community confined to the area near the stream

Crystal structures of racemic and enantiomeric 5-isopropyl-5-methylhydantoin

Crystal structures of racemic and enantiomeric 5-isopropyl-5-methylhydantoin (IPrMH) have been determined by single crystal X-ray diffraction. Melting temperatures and solid state infrared spectra are also measured. Racemic IPrMH has a lower melting temperature than the pure enantiomer by 25 °C. The infrared spectrum of racemic IPrMH is identical with that of the pure enantiomer. Nevertheless, the racemic IPrMH doesn’t crystallize as a conglomerate but as a racemic compound. The racemic and the enantiomeric crystals are very similar to each other in molecular geometries and intermolecular interactions. In the both cases, the molecules are connected via N−H···O hydrogen bonds to form R22(8) rings, and these rings are linked into infinite one-dimensional tapes. In the racemic crystal, a single tape is composed of single enantiomer and itself is homochiral

Effect of cyclodextrins on the thermal epimerization of tea catechins

金沢大学理工研究域物質化学系The epimerization reaction of tea catechins was investigated at pH 5.5 and 120°C in the absence/presence of cyclodextrins (CDs). In the absence of CDs, a considerable quantity (∼20%) of products originating from reactions other than the epimerization ("other products") was formed during the epimerization of gallated catechins. In the case of (-)-EGCg, addition of β-CD to the reaction solution reduced the quantity of these other products to just a few percent, but other CDs with different cavity sizes had little effect. Generally, the addition of β-CD increased the ratio of non-epi type catechins, that is, [non-epi type catechin] / ([epi type catechin]+[non-epi type catechin]). Molecular orbital (MO) calculations using the PM3 method suggested that non-epi type catechins are more thermodynamically stable than their epi-type counterparts, moving the equilibrium position in favor of non-epi type catechins in the epimerization process

Synthesis and crystal structure of (S)-5-isopropyl-5-methyl-2-thiohydantoin

(S)-5-Isopropyl-5-methyl-2-thiohydantoin was synthesized by one-pot reaction of α-methyl-L-valine and thiourea in the absence of solvent. The crystal structure of this compound has been determined from single crystal X-ray diffraction data. This is the first report on the crystal structure of a homochiral 5-substituted 2-thiohydantoin with the unsubstituted NH groups. This compound, C7H12N2OS crystallizes in the chiral orthorhombic space group P212121 with four molecules in the unit cell. The unit cell parameters are: a = 8.2798(12) Å, b = 8.6024(13) Å, c = 12.826(2) Å and V = 913.6(2) Å3. In the crystals, the thioamide and amide N-H of one molecule are hydrogen-bonded to the thioamide C=S group of neighboring molecules to form rings with the R22(8) graph-set motif, and these rings are linked into infinite one-dimensional tapes