Anekomochi glutinous rice provides low postprandial glycemic response by enhanced insulin action via GLP-1 release and vagal afferents activation.

Glutinous rice (mochi rice), compared to non-glutinous rice (uruchi rice), exhibits a wide range of glycemic index (GI) values, from low to high. However, the underlying mechanisms behind the variation in GI values remain poorly understood. In this study, we aimed to identify rice cultivars with a low postprandial glycemic response and investigate the mechanisms, focusing on insulin and incretin hormones.

A large deletion within intron 20 sequence of single-copy gene as a useful marker for the speciation in AA-genome species.

AA-genome complex comprises five wild species, , , , , and . Evolutionary relationships among these five wild species have remained contentious and inconclusive. We found that intron 20 of , a single-copy nuclear gene, was short (S-type: 141-142 bp) in , , and , while long (L-type: 1.

Raman spectroscopic analysis of polysaccharides in popular Japanese rice cultivars.

Analytical algorithms based on Raman spectroscopy are proposed for the determination of amylopectin and amylose concentrations in polished white rice, and applied to characterize and compare linear and branched polysaccharide structures in nine different types of Japanese rice. A selected algorithm used symmetric bending vibrations of the COC glycosidic linkage from a relatively narrow spectral zone between 830 and 895 cm. It specifically compared the intensity of Raman signals from two types of bending common to both starch components (C1-O-C5 and C1-O-C4 at 868 and 855 cm, respectively) and that at the branch point peculiar to amylopectin (C1-O-C6 at 844 cm).

Genetic diversity of preserved rice seed samples from the Mikawa area, Japan, stored in the Meiji era.

Preserved rice ( L.) seeds stored for nearly a century as an emergency food stocks from the Mikawa area were investigated for their genetic diversity. Morphologically, the seeds appeared to be typical Japonica.

Diverse genetic variation in maternal lineages with high heterogeneity among -conserved wild rice ( Griff.) developed in Thailand.

Wild rice, , is a genetic resource that can be used to improve cultivated rice, but its populations are now decreasing in terms of both size and number. Extensive research on wild rice has been conducted in Thailand, where two conservation sites have been preserved in natural areas where perennial wild rice predominates. The genetic structure of wild rice populations was investigated by examining both the chloroplast and nucleus genomes at sites of conservation site in Thailand.

Understanding and monitoring the consequences of human impacts on intraspecific variation.

Intraspecific variation is a major component of biodiversity, yet it has received relatively little attention from governmental and nongovernmental organizations, especially with regard to conservation plans and the management of wild species. This omission is ill-advised because phenotypic and genetic variations within and among populations can have dramatic effects on ecological and evolutionary processes, including responses to environmental change, the maintenance of species diversity, and ecological stability and resilience. At the same time, environmental changes associated with many human activities, such as land use and climate change, have dramatic and often negative impacts on intraspecific variation.

Genetic diversity of the flanking region in rice landraces in northern Laos.

A glutinous texture of endosperm is one of the important traits of rice ( L.). Northern Laos is known as a center of glutinous rice diversity.

Molecular relationships between Australian annual wild rice, Oryza meridionalis, and two related perennial forms.

Background: The perennial, Oryza rufipogon distributed from Asia to Australia and the annual O. meridionalis indigenous to Australia are AA genome species in the Oryza. However, recent research has demonstrated that the Australian AA genome perennial populations have maternal genomes more closely related to those of O.

Diversification and genetic differentiation of cultivated melon inferred from sequence polymorphism in the chloroplast genome.

Molecular analysis encouraged discovery of genetic diversity and relationships of cultivated melon (Cucumis melo L.). We sequenced nine inter- and intra-genic regions of the chloroplast genome, about 5500 bp, using 60 melon accessions and six reference accessions of wild species of Cucumis to show intra-specific variation of the chloroplast genome.

Population structural analysis of an in-situ conservation site for wild rice in Laos.

An in-situ conservation site in Laos for a mixture of annual and perennial wild rice, LV27, which is a single swamp with an observation pier has been developed. In order to develop a strategy for evaluation of natural resources, systematic leaf sampling has been conducted and their genetic characteristics measured with 16 SSR loci. In order to determine population structure, a small number of individuals localized together were regarded as sub-populations belonging to a single mother population.

Genetic variation in the chloroplast genome suggests multiple domestication of cultivated Asian rice (Oryza sativa L.).

Two hundred and seventy-five accessions of cultivated Asian rice and 44 accessions of AA genome Oryza species were classified into 8 chloroplast (cp) genome types (A-H) based on insertion-deletion events at 3 regions (8K, 57K, and 76K) of the cp genome. The ancestral cp genome type was determined according to the frequency of occurrence in Oryza species and the likely evolution of the variable 57K region of the cp genome. When 2 nucleotide substitutions (AA or TT) were taken into account, these 8 cp types were subdivided into 11 cp types.