Isozymes and classification of Asian rice varieties

1987

Euphytica, 1997

Magnitudes of genetic variation within each of major varietal groups of cultivated rice were surveyed in terms of isozyme polymorphism and allelic differentiation of hybrid sterility loci, both of which are considered to have litt le selective value. Allelic differences for 20 isozyme loci were examined in a total of 337 accessions, including Indica and Japonica rices. Aus cultivars from India, Javanica cultivars and both landraces and cultivars from China. Eleven out of the 20 isozyme loci were polymorphic. The Aus cultivars contained more alleles per locus than others. The hybrid sterilities in the crosses among Chinese cultivars, Indica and Japonica cultivars were mainly controlled by locus S-5, whereas the hybrid sterilities of Aus cultivars, when they were crossed to Indica, Japonica or Javanica cultivars, were found to be controlled by allelic interaction at hybrid sterility loci S-5, S-7, S-9 and S-15. Also in terms of the number of alleles at S-5 and S-7, Aus cultivars contained more alleles than others. While the Aus group showed an extreme diversity for both hybrid sterility alleles and isozymes, modern cultivars from the south of YangZi River in China were classified into Indica type and those from the north were into Japonica, which were almost the same as those in Japan. On the basis of the measured polymorphism the Indica-Japonica differentiation was explained by founder effects, i.e., through selection and distribution of two original sources each with a unique set of markers. Contrastingly, the continuous and pronounced diversity in the Aus group was attributed to the absence of such a process. The intermediate groups in Yunnan province and Tai-hu Lake region of China are considered to be isolated from such founder effects, retaining an intermediate diversity in terms of isozymes and hybrid sterility genes. Since hybrid sterility hampers the exchange of genes between cultivars of different groups, the understanding of its genetic basis will be important in rice breeding, particularly in hybrid rice breeding.

Theoretical and Applied Genetics, 1987

Journal of Agricultural and Food Chemistry, 2009

Indian Journal of Agricultural Sciences

A study was carried out for characterization of 60 farmers’ varieties using grain characters and 40 SSR (Simple Sequence Repeat) markers. Only a set of 8 (20%) primers were polymorphic yielding 16 bands (alleles) among these 60 varieties. The size of amplicons ranged from 120 bp (RM238) to 240 bp (RM551). The number of alleles per microsatellite ranged from 1 (RM238, RM119 and RM120) to 3 (RM259, RM234 and RM551) with an average of 2 alleles per locus. Major allele frequency ranged from 0.51 to 0.97 averaging 0.74. Genetic diversity ranged from 0.045 to 0.588 with a mean of 0.34. Considering the entire genotypic array, the mean value for polymorphism information content (PIC) for all microsatellites was 0.27. Microsatellite RM122 with 2 alleles had the maximum PIC value (0.37) and the microsatellite RM205 with 2 alleles had the minimum (0.27) value. The UPGMA cluster analysis grouped varieties into three main clusters with 58% genetic similarity and homing 24, 23 and 13 varieties, r...

2020

In this study phylogenetics and diversity of 150 rice (Oryza sativa L.) genotypes originated from different regions of an agricultural country Pakistan, self-sufficient in its production were analyzed. Total seed protein profile of these genotypes was assessed using a technique of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The seeds of accessions from different geographical regions of the country were provided by the Institute of Agri-Biotechnology and Genetic Resources, National Agricultural Research Centre (IABGRI-NARC) Islamabad, Pakistan. Total endosperm proteins from each genotype were extracted and used as biochemical markers. Three different protein extraction protocols were followed in comparison to optimize the procedure. An immense content of genetic variability was confirmed based on polymorphism data of polypeptide bands. The Jaccard’s dissimilarity coefficient ranged from 0.09–0.94 for all 150 accessions. Based on the neighbour joining method...

2012

Acta Musei Nationalis Pragae – Historia litterarum, 2020

The article describes the lives of several Czech-French female ‘heroines’, writers and scientists active in the first half of the 20th century who we encountered in connection with research into book provenances in Czech and French institutions and whose fates are little known, or even unknown, to the Czech and French cultural public. The first part, entitled ‘Paris in Prague and Prague in Paris’, tells the story of two women, a Francophone Belgian and a Czech living in France. The second part, ‘French Women Married to Czechs’, maps the lives of three French women who were engaged in pedagogical, translation, educational and scientific activities and who were forced to leave Czechoslovakia after 1948 for political reasons. The last part, ‘The Daughter of a Famous Father’, deals with the life of the Bohemist Jacqueline Mazon, the daughter of the distinguished French Slavist André Mazon.