Abstract
Acca sellowiana, known as feijoa or pineapple guava, is a diploid, (2n = 2x = 22) outcrossing fruit tree species native to Uruguay and Brazil. The species stands out for its highly aromatic fruits, with nutraceutical and therapeutic value. Despite its promising agronomical value, genetic studies on this species are limited. Linkage genetic maps are valuable tools for genetic and genomic studies, and constitute essential tools in breeding programs to support the development of molecular breeding strategies. A high-density composite genetic linkage map of A. sellowiana was constructed using two genetically connected populations: H5 (TCO × BR, N = 160) and H6 (TCO × DP, N = 184). Genotyping by sequencing (GBS) approach was successfully applied for developing single nucleotide polymorphism (SNP) markers. A total of 4,921 SNP markers were identified using the reference genome of the closely related species Eucalyptus grandis, whereas other 4,656 SNPs were discovered using a de novo pipeline. The individual H5 and H6 maps comprised 1,236 and 1,302 markers distributed over the expected 11 linkage groups, respectively. These two maps spanned a map length of 1,593 and 1,572 cM, with an average inter-marker distance of 1.29 and 1.21 cM, respectively. A large proportion of markers were common to both maps and showed a high degree of collinearity. The composite map consisted of 1,897 SNPs markers with a total map length of 1,314 cM and an average inter-marker distance of 0.69. A novel approach for the construction of composite maps where the meiosis information of individuals of two connected populations is captured in a single estimator is described. A high-density, accurate composite map based on a consensus ordering of markers provides a valuable contribution for future genetic research and breeding efforts in A. sellowiana. A novel mapping approach based on an estimation of multipopulation recombination fraction described here may be applied in the construction of dense composite genetic maps for any other outcrossing diploid species.
Highlights
Acca sellowiana (Berg.) Burret, commonly known as feijoa or pineapple guava, is an agronomically promising fruit tree species, native to Uruguay and southern Brazil
We constructed the first high-density genetic map for A. sellowiana using a genotyping by sequencing approach
The Genotyping by sequencing (GBS) protocol was an effective strategy for simultaneous single nucleotide polymorphism (SNP) discovery and genotyping, identifying thousands of genomewide polymorphic markers, in a species with limited genetic resources
Summary
Acca sellowiana (Berg.) Burret, commonly known as feijoa or pineapple guava, is an agronomically promising fruit tree species, native to Uruguay and southern Brazil. This diploid (2n = 2x = 22) outcrossing species presents a small genome (245 Mb) (da Costa et al, 2008) and the basic haploid number of n = 11, largely conserved in the Myrtaceae family (Grattapaglia et al, 2012). Like feijoa, the breeding process is slow and costly because of the long juvenile period, extensive phenotyping cost, and limited field space (Byrne, 2012) For this reason, the development of genetic and genomic resources, such as genetic maps, represents a suitable strategy to overcome these limitations and speed up the breeding progress
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
