Genetic diversity and population structure of Saccharum hybrids

• Published in: PloS one Vol. 18; no. 8; p. e0289504
• Main Authors: Perera, María Francisca, Ostengo, Santiago, Malavera, Andrea Natalia Peña, Balsalobre, Thiago Willian Almeida, Onorato, Guilherme Dias, Noguera, Aldo Sergio, Hoffmann, Hermann Paulo, Carneiro, Monalisa Sampaio
• Format: Journal Article
• Language: English
• Published: San Francisco Public Library of Science 15-08-2023
• Subjects: Bayesian analysis; Biology and Life Sciences; Brown rust; Computer and Information Sciences; Cultivars; Disease; Disease resistance; DNA polymerase; Ecology and Environmental Sciences; Engineering and Technology; Ethanol; Exchanging; Gene pool; Genes; Genetic analysis; Genetic aspects; Genetic diversity; Genetic structure; Genetic testing; Genotypes; Germplasm; Haplotypes; Hybrids; Identification and classification; Lignin; Metabolism; Multidimensional scaling; Physical Sciences; Plant breeding; Population genetics; Population structure; Production management; Saccharum; Similarity; Sucrose; Sugar industry; Sugarcane; Variance analysis; Brazil; Argentina; Louisiana; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0289504

Sugarcane breeding programs incorporate foreign material to broaden the genetic base, expanding the gene pool. In South America, the Inter-university Network for the Development of the Sugarcane Industry (RIDESA) and Estación Experimental Agroindustrial Obispo Colombres (EEAOC) sugarcane breeding programs from Brazil and Argentina, respectively, have never exchanged materials. In that sense, the knowledge of the genetic diversity and population structure among sugarcane genotypes of both germplasm banks, determined in a reliable way through their molecular profiles, will provide valuable information to select the best parental accessions for crossing aimed at the efficient introgression of desirable alleles. For that, the aim was to determine the genetic diversity and population structure of 96 Saccharum commercial hybrids from RIDESA and EEAOC sugarcane breeding programs by using TRAP, SSR and markers related to disease resistance (e.g. Bru1 and G1). Genetic structure was determined through genetic similarity analysis, analysis of molecular variance (AMOVA), Multidimensional scaling (MDS), and a Bayesian method. Average PIC values were 0.25 and 0.26, Ho values were 0.24 and 0.28, and He values were 0.25 and 0.28, for TRAP and SSR primers, respectively. Genetic similarity, MDS, and analysis of structure revealed that Brazilian and Argentinean genotypes clustered in two groups clearly differentiated, whereas AMOVA suggested that there is more variability within programs than between them. Regarding Bru1 markers, Brazilian genotypes showed high frequency of haplotype 1 (71.4%) whereas Argentinean genotypes showed high frequency of haplotype 4 (80.8%); haplotypes 1 and 4 are indicated for the presence and absence of the brown rust resistance gene (Bru1), respectively. Respecting the G1 marker, most of the evaluated genotypes (60.4%) showed the presence of the fragment, in a similar proportion for genotypes of both programs. In conclusion, the exchange of materials, at least the most diverse genotypes, between RIDESA and EEAOC breeding programs will allow extending the genetic base of their germplasm banks, and the knowledge of genetic diversity will help breeders to better manage crosses, increasing the probability of obtaining more productive varieties.