CHARACTERIZATION OF 35 NEW MICROSATELLITE GENETIC MARKERS FOR THE PACIFIC WHITELEG SHRIMP, LITOPENAEUS VANNAMEI: THEIR USEFULNESS FOR STUDYING GENETIC DIVERSITY OF WILD AND CULTURED STOCKS, TRACING PEDIGREE IN BREEDING PROGRAMS, AND LINKAGE MAPPING

The conservation and characterization of grape (Vitis spp) genetic resources in germplasm banks have been the basis of its use in breeding programs that result in development of new cultivars. There are at least 10,000 grape cultivars kept in germplasm collection. The genetic diversity in 136 table grape accessions from the state of Bahia, Brazil, was evaluated. Continuous and discrete morphoagronomic traits were assessed. The clustering analysis by the Tocher otimization method resulted in 30 clusters (considering continuous morphoagronomic traits), and 9 clusters (taking into consideration multicategorical traits). There was no agreement between clusters obtained by both, continuous or discrete phenotypic descriptors, independent of the cluster method analysis used. A satisfactory genetic variability among the table grape accessions was observed.

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Ampelographic characterization of white grapevine cul-tivars (Vitis vinifera L.) grown in Palestine

مجلة جامعة فلسطين التقنية للأبحاث ◽

10.53671/pturj.v3i1.34 ◽

2015 ◽

Vol 3 (1) ◽

pp. 1-11

Author(s):

Rezq Basheer-Salimia

Keyword(s):

Genetic Diversity ◽

Genetic Distance ◽

Germplasm Conservation ◽

Genetic Distances ◽

Vitis Vinifera L ◽

Similarity Matrix ◽

Breeding Programs ◽

Local Varieties ◽

Synonymies And Homonymies

Abstract: In Palestine, grape culture consists of ecotypes and cultivars (also called local varieties), for which a large number of homonymous and synonymous designations exist as well as misnaming of cultivars. The present study is the first report using detailed ampelographic characterizations (39 informative traits) to assess genetic diversity and detect similarities among sixteen accessions collected from putative diverse grape genotypes In general, 30 descriptors presented highly and satisfactory divergent genotypes, whereas the remaining traits showed no or very little ampelographic variation. Based on the similarity matrix and the resulting dendrogram of these ampelographic data, distinguishable genotypes as well as some cases of synonymies and homonymies clearly exist. A synonymy case seemed to be in four genotypes including Jandali-Mfarad, Jan-dali-Mrazraz, Jandali, and Hamadani-Mattar, which indeed showed genetic distances of less than 0.5, sug-gesting their relatedness, and the possibility that they are the same genotype, but with different names. In addition, homonym cases also occur in the following pairs of “Marawi’s, Hamadani’s, and Zaini’s genotypes, in which each pair seems to be two distinctive genotypes. Finally, among the 16 examined genotypes, the Zaini-Baladi genotype tended to show the highest genetic distance values from the others and thus could be potentially incorporated into any further local or regional breeding programs as well as germplasm conservation.

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Phenotypic and molecular characterization of a set of tropical maize inbred lines from a public breeding program in Brazil

BMC Genomics ◽

10.1186/s12864-021-08127-7 ◽

2022 ◽

Vol 23 (1) ◽

Author(s):

Sirlene Viana de Faria ◽

Leandro Tonello Zuffo ◽

Wemerson Mendonça Rezende ◽

Diego Gonçalves Caixeta ◽

Hélcio Duarte Pereira ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Inbred Lines ◽

Breeding Program ◽

Tropical Maize ◽

Maize Breeding ◽

Breeding Programs ◽

The Public ◽

Maize Inbred Lines

Abstract Background The characterization of genetic diversity and population differentiation for maize inbred lines from breeding programs is of great value in assisting breeders in maintaining and potentially increasing the rate of genetic gain. In our study, we characterized a set of 187 tropical maize inbred lines from the public breeding program of the Universidade Federal de Viçosa (UFV) in Brazil based on 18 agronomic traits and 3,083 single nucleotide polymorphisms (SNP) markers to evaluate whether this set of inbred lines represents a panel of tropical maize inbred lines for association mapping analysis and investigate the population structure and patterns of relationships among the inbred lines from UFV for better exploitation in our maize breeding program. Results Our results showed that there was large phenotypic and genotypic variation in the set of tropical maize inbred lines from the UFV maize breeding program. We also found high genetic diversity (GD = 0.34) and low pairwise kinship coefficients among the maize inbred lines (only approximately 4.00 % of the pairwise relative kinship was above 0.50) in the set of inbred lines. The LD decay distance over all ten chromosomes in the entire set of maize lines with r2 = 0.1 was 276,237 kb. Concerning the population structure, our results from the model-based STRUCTURE and principal component analysis methods distinguished the inbred lines into three subpopulations, with high consistency maintained between both results. Additionally, the clustering analysis based on phenotypic and molecular data grouped the inbred lines into 14 and 22 genetic divergence clusters, respectively. Conclusions Our results indicate that the set of tropical maize inbred lines from UFV maize breeding programs can comprise a panel of tropical maize inbred lines suitable for a genome-wide association study to dissect the variation of complex quantitative traits in maize, mainly in tropical environments. In addition, our results will be very useful for assisting us in the assignment of heterotic groups and the selection of the best parental combinations for new breeding crosses, mapping populations, mapping synthetic populations, guiding crosses that target highly heterotic and yielding hybrids, and predicting untested hybrids in the public breeding program UFV.

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Genetic diversity within and between broodstocks of the white shrimp Litopenaeus vannamei (Boone, 1931) (Decapoda, Penaeidae) and its implication for the gene pool conservation

Brazilian Journal of Biology ◽

10.1590/s1519-69842007000500019 ◽

2007 ◽

Vol 67 (4 suppl) ◽

pp. 939-943 ◽

Cited By ~ 15

Author(s):

PD. Freitas ◽

MR. Calgaro ◽

PM. Galetti Jr.

Keyword(s):

Genetic Diversity ◽

Genetic Variation ◽

Litopenaeus Vannamei ◽

Gene Pool ◽

Rapd Analysis ◽

Pacific White Shrimp ◽

White Shrimp ◽

Brazilian Coast ◽

The Pacific ◽

Improvement Programs

Genetic variation within and between fifteen closed broodstock lines of the Pacific white shrimp Litopenaeus vannamei, reared at different hatcheries in the Brazilian coast, was assessed by RAPD analysis. Fifty two polymorphic loci were identified when a set of five decamer primers was used in PCR. The genetic diversity analysis within lines evidenced genetic variation loss probably related to bottleneck effects and inbreeding. In addition, the genetic divergence values between the different samples appear to reflect the initial founder composition of such stocks, in some cases, sharing a common origin, suggesting a putative importance of interbreeding for the establishment of genetic improvement programs for these broodstocks. The genetic variation monitoring appears to be helpful to the gene pool conservation of this aquaculture species, mainly if considered its exotic status in Brazil and the current impossibility of new introduction of wild individuals.

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