Genetic Diversity of Tropical Hybrid Rice Germplasm Measured by Molecular Markers

To maximize heterosis, it is important to understand the genetic diversity of germplasm and associate useful phenotypic traits such as fertility restoration for hybrid rice breeding. The objectives of the present study were to characterize genetic diversity within a set of rice germplasm groups using coefficient of parentage (COP) values and 58 simple sequence repeat (SSR) markers for 124 genotypes having different attributes such as resistance/tolerance to various biotic and abiotic stresses. These lines were also used for identifying prospective restorers and maintainers for wild abortive-cytoplasmic male sterile (CMS) line. The mean COP value for all the lines was 0.11, indicating that the genotypes do not share common ancestry. The SSR analysis generated a total of 268 alleles with an average of 4.62 alleles per locus. The mean polymorphism information content value was 0.53, indicating that the markers selected were highly polymorphic. Grouping based on COP analysis revealed three major clusters pertaining to the indica, tropical japonica and japonica lines. A similar grouping pattern with some variation was also observed for the SSR markers. Fertility restoration phenotype based on the test cross of the 124 genotypes with a CMS line helped identify 23 maintainers, 58 restorers and 43 genotypes as either partial maintainers or partial restorers. This study demonstrates that COP analysis along with molecular marker analysis might encourage better organization of germplasm diversity and its use in hybrid rice breeding. Potential restorers identified in the study can be used for breeding high-yielding stress-tolerant medium-duration rice hybrids, while maintainers would prove useful for developing new rice CMS lines.

Download Full-text

Genetic Diversity Evaluation and Conservation of Kam Fragrant Glutinous Rice (Oryza sativa L.) Germplasm in Southeast Guizhou, China

Plants ◽

10.3390/plants10091898 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1898

Author(s):

Qi-Yi Lei ◽

Jiang-Ju Zhou ◽

Yong Xiong ◽

Wen-Hua Zhang ◽

Jing Luo ◽

...

Keyword(s):

Genetic Diversity ◽

Molecular Markers ◽

Cultural Anthropology ◽

Germplasm Resources ◽

Growth Environment ◽

Folk Classification ◽

Rice Germplasm ◽

Glutinous Rice ◽

Traditional Cultures ◽

High Level

The genetic diversity of rice germplasm is the basis for increases in rice yield and quality. The collection, assessment, and protection of the genetic diversity of rice germplasm is important for achieving sustainable agriculture and assuring food security. Many underdeveloped indigenous areas have abundant and valuable rice germplasm resources. However, in-depth assessments of the genetic diversity of rice germplasm from these areas and studies related to protecting these traditional cultures are not available. In this study, from 2005 to 2016, the authors have conducted in-depth evaluation of the genetic diversity of Kam fragrant glutinous rice germplasm resources in southeast Guizhou by using multidisciplinary comprehensive methods such as ethnobotany, cultural anthropology, and modern molecular markers. In total, 376 Kam fragrant glutinous rice samples from 42 villages in the Dong community in southeast Guizhou were collected. Agronomic traits of panicles were complex and exhibited diversity. Some varieties had good disease resistance and adaptation to cold and wet climates. The Dong people named the Kam fragrant glutinous rice varieties by using seven elements, including diverse traits, growth environment, and origin. Traditional folk classification, in addition to morphology and biological analysis using molecular markers, indicates that Kam fragrant glutinous rice includes 91 varieties. Kam fragrant glutinous rice comprises a very high number of varieties, most of which are japonica-type and exhibit a high level of genetic diversity. The traditional folk classification of Kam fragrant glutinous rice by the Dong community is consistent with the biological classification. The traditional naming of Kam fragrant glutinous rice provides an important reference for understanding its genetic diversity. The high level of genetic diversity in Kam fragrant glutinous rice is not only related to the natural environment of the area but also tightly linked with the abundant and diverse Dong ethnic traditional cultures, which has led to protection of Kam fragrant glutinous rice’s genetic diversity.

Download Full-text

Comparative analysis of genetic diversity ofDosidicus gigasfrom eastern Pacific Ocean based on molecular markers of mitochondrial DNA

JOURNAL OF FISHERIES OF CHINA ◽

10.3724/sp.j.1231.2013.38490 ◽

2013 ◽

Vol 37 (11) ◽

pp. 1618

Author(s):

Lianw ei LIU ◽

Qianghua XU ◽

Xinjun CHEN ◽

Jie YAN ◽

Wei YU ◽

...

Keyword(s):

Genetic Diversity ◽

Mitochondrial Dna ◽

Molecular Markers ◽

Comparative Analysis ◽

Pacific Ocean ◽

Eastern Pacific ◽

Eastern Pacific Ocean

Download Full-text

Genetic Diversity of Basil (Ocimum spp. - Lamiaceae) Based on RAPD Markers and Volatile Oil Constituents

HortScience ◽

10.21273/hortsci.33.3.492f ◽

1998 ◽

Vol 33 (3) ◽

pp. 492f-493

Author(s):

Roberto F. Vieira ◽

James E. Simon ◽

Peter Goldsbrough ◽

Antonio Figueira

Keyword(s):

Genetic Diversity ◽

Molecular Markers ◽

Rapd Markers ◽

Volatile Oil ◽

Essential Oil Composition ◽

Oil Composition ◽

Traditional Medicines ◽

The Tropics ◽

High Degree ◽

First Time

Essential oils extracted from basil (Ocimum spp.) by steam distillation are used to flavor foods, oral products, in fragrances, and in traditional medicines. The genus Ocimum contains around 30 species native to the tropics and subtropics, with some species naturalized and/or cultivated in temperate areas. Interand intraspecific hybridization have created significant confusion in the botanical systematics of this genus. Taxonomy of basil (O. basilicum) is also complicated by the existence of numerous varieties, cultivars, and chemotypes within the species that do not differ significantly in morphology. In this study we are using RAPD markers and volatile oil composition to characterize the genetic diversity among the most economically important Ocimum species. We hypothesize that the genetic similarity revealed by molecular markers will more accurately reflect the morphological and chemical differences in Ocimum than essential oil composition per se. Preliminary research using five Ocimum species, four undetermined species, and eight varieties of O. basilicum (a total of 19 accessions) generated 107 polymorphic fragments amplified with 19 primers. RAPDs are able to discriminate between Ocimum species, but show a high degree of similarity between O. basilicum varieties. The genetic distance between nine species and among 55 accessions within the species O. americanum, O. basilicum, O. campechianum, O. × citriodorum, O. gratissimum, O. kilimandscharium, O. minimum, O. selloi, and O. tenuiflorum will be analyzed by matrix of similarity and compared to the volatile oil profile. This research will for the first time apply molecular markers to characterize the genetic diversity of Ocimum associate with volatile oil constituent.

Download Full-text

Assessment of genetic diversity of pumpkins (Cucurbita spp.) from western Kenya using SSR molecular markers

Molecular Biology Reports ◽

10.1007/s11033-021-06245-9 ◽

2021 ◽

Vol 48 (3) ◽

pp. 2253-2260

Author(s):

Lameck A. Nyabera ◽

Inosters W. Nzuki ◽

Steven M. Runo ◽

Peris W. Amwayi

Keyword(s):

Genetic Diversity ◽

Molecular Markers ◽

Western Kenya

Download Full-text

Molecular markers and antioxidant activity in berry crops: Genetic diversity analysis

Canadian Journal of Plant Science ◽

10.4141/cjps2011-240 ◽

2012 ◽

Vol 92 (6) ◽

pp. 1121-1133 ◽

Cited By ~ 9

Author(s):

S. C. Debnath ◽

Y. L. Siow ◽

J. Petkau ◽

D. An ◽

N. V. Bykova

Keyword(s):

Genetic Diversity ◽

Antioxidant Activity ◽

Molecular Markers ◽

Molecular Techniques ◽

Diversity Analysis ◽

Full Potential ◽

Genetic Diversity Analysis ◽

Wide Range ◽

Berry Crops ◽

Improvement Programs

Debnath, S. C., Siow, Y. L., Petkau, J., An, D. and Bykova, N. V. 2012. Molecular markers and antioxidant activity in berry crops: Genetic diversity analysis. Can. J. Plant Sci. 92: 1121–1133. An improved understanding of important roles of dietary fruits in maintaining human health has led to a dramatic increase of global berry crop production. Berry fruits contain relatively high levels of vitamin C, cellulose and pectin, and produce anthocyanins, which have important therapeutic values, including antitumor, antiulcer, antioxidant and anti-inflammatory activities. There is a need to develop reliable methods to identify berry germplasm and assess genetic diversity/relatedness for dietary properties in berry genotypes for practical breeding purposes through genotype selection in a breeding program for cultivar development, and proprietary-rights protection. The introduction of molecular biology techniques, such as DNA-based markers, allows direct comparison of different genetic materials independent of environmental influences. Significant progress has been made in diversity analysis of wild cranberry, lowbush blueberry, lingonberry and cloudberry germplasm, and in strawberry and raspberry cultivars and advanced breeding lines developed in Canada. Inter simple sequence repeat (ISSR) markers detected an adequate degree of polymorphism to differentiate among berry genotypes, making this technology valuable for cultivar identification and for the more efficient choice of parents in the current berry improvement programs. Although multiple factors affect antioxidant activity, a wide range of genetic diversity has been reported in wild and cultivated berry crops. Diversity analysis based on molecular markers did not agree with those from antioxidant activity. The paper also discusses the issues that still need to be addressed to utilize the full potential of molecular techniques including expressed sequence tag-polymerase chain reaction (EST-PCR) analysis to develop improved environment-friendly berry cultivars suited to the changing needs of growers and consumers.

Download Full-text