Genetic Diversity, Erosion, and Population Structure in Cotton Genetic Resources

Author(s):  
Narayanan Manikanda Boopathi ◽  
Lucia Vieira Hoffmann
2019 ◽  
Author(s):  
Tiago do Prado Paim ◽  
Samuel Rezende Paiva ◽  
Natália Martins de Toledo ◽  
Michel Beleza Yamaghishi ◽  
Paulo Luiz Souza Carneiro ◽  
...  

AbstractBrazilian hair sheep constitute a genetic diversity hotspot of sheep breeds. These locally adapted genetic resources developed in harsh environments of the Brazilian Northwest (semi-arid) and maintained important traits for this region, such as parasite resistance, heat tolerance and high pelt quality. Genotypes (50K SNP chip) from seven Brazilian sheep breeds (5 hair and 2 coarse wool types) and 87 worldwide breeds were used to verify population structure, admixture and genetic diversity, using PCA and ADMIXTURE analyses. We constructed a phylogenetic tree and evaluated migration events between genetic groups using TREEMIX software. Brazilian Somali, a fat-tailed breed, was the unique breed with high relationship with East African breeds and formed a distinct cluster from other Brazilian breeds. This breed seems to contribute to formation of Santa Inês, Morada Nova and Brazilian Fat-tail breeds. Brazilian Blackbelly had a clear relationship with Barbados Blackbelly, which appeared as another group. Other Brazilian breeds seem to form a further genetic group with some recent admixtures. Morada Nova remained as a separate group, not showing a strong relationship with European or African breeds, only revealing a migration event from Sidaoun, an Algerian hair breed. Brazilian Fat-tail and Morada Nova share a common ancestor, but the first received introgressions from Brazilian Somali and Afrikaner breeds, explaining the fat-tail phenotype. Santa Inês received strong contribution from Bergamasca and had an admixed origin with recent introgressions from other breeds, mainly from Suffolk animals. In conclusion, Brazilian Somali and Brazilian Fat-tail are the most endangered sheep genetic resources in Brazil.


Genes ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 281 ◽  
Author(s):  
Fu-Mei Liu ◽  
Ning-Nan Zhang ◽  
Xiao-Jin Liu ◽  
Zeng-Jiang Yang ◽  
Hong-Yan Jia ◽  
...  

Dalbergia odorifera T. Chen (Fabaceae) is a woody tree species indigenous to Hainan Island in China. Due to its high medicinal and commercial value, this tree species has been planted over 3500 ha2 in southern China. There is an urgent need for improvement of the D. odorifera germplasm, however, limited information on germplasm collection, conservation, and assessment of genetic resources is available. Therefore, we have built a database of 251 individuals collected across the whole of southern China, which included 42 wild trees and 210 cultivated trees, with the following objectives. (1) Evaluate genetic diversity and population structure of the database using 19 microsatellite markers and (2) develop a core collection for improvement and breeding programs. Totally, the 19 microsatellite markers harbored 77 alleles across the database with the polymorphic information content (PIC) ranging from 0.03 to 0.66. Medium genetic diversity level was inferred by Nei’s gene diversity (0.38), Shannon’s information index (0.65), and observed (0.33) and expected heterozygosity (0.38). Structure analysis showed that four was the optimum cluster size using the model-based Bayesian procedure, and the 251 D. odorifera individuals were grouped into five populations including four pure ones (RP1-4) and one mixed one (MIX) based on their maximum membership coefficients. Among these populations, the expected heterozygosity varied from 0.30 (RP3) to 0.38 (RP4). Analysis of molecular variance (AMOVA) showed 11% genetic variation existed among populations, and moderate population differentiation was inferred by the matrix of pairwise Fst (genetic differentiation among populations), which was in the range of 0.031 to 0.095. Moreover, a core collection of 31 D. odorifera individuals including six wild and 25 cultivated trees was developed, which was only 12.4% of the database but conserved the whole genetic diversity. The results of this study provided additional insight into the genetic structure of the large D. odorifera germplasm, and the core collection will be useful for the efficient and sustainable utilization of genetic resources, as well as efficient improvement in breeding programs.


2011 ◽  
Vol 59 (4) ◽  
pp. 517-538 ◽  
Author(s):  
Elena Albrecht ◽  
Dapeng Zhang ◽  
Robert A. Saftner ◽  
John R. Stommel

2020 ◽  
Vol 52 (6) ◽  
Author(s):  
Anpei Zhou ◽  
Dan Zong ◽  
Peihua Gan ◽  
Yao Zhang ◽  
Dan Li ◽  
...  

2014 ◽  
Vol 21 (6) ◽  
pp. 723-731
Author(s):  
Xu Gangbiao ◽  
Liang Yan ◽  
Jiang Yan ◽  
Liu Xiongsheng ◽  
Hu Shangli ◽  
...  

2010 ◽  
Vol 36 (5) ◽  
pp. 744-753 ◽  
Author(s):  
Ting-Ting QIAO ◽  
Chun-Lei MA ◽  
Yan-Hua ZHOU ◽  
Ming-Zhe YAO ◽  
Rao LIU ◽  
...  

2013 ◽  
Vol 38 (12) ◽  
pp. 2286-2296 ◽  
Author(s):  
Wen-Di YUE ◽  
Li-Bin WEI ◽  
Ti-De ZHANG ◽  
Chun LI ◽  
Hong-Mei MIAO ◽  
...  

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