Genetic diversity and population structure analysis of accessions in the US historic sweet sorghum collection

Abstract

Sweet sorghum has the potential to become a versatile feedstock for large-scale bioenergy production given its sugar from stem juice, cellulose/hemicellulose from stalks, and starch from grain. However, for researchers to maximize its feedstock potential a first step includes additional evaluations of the 2,180 accessions with varied origins in the US historic sweet sorghum collection. To assess genetic diversity of this collection for bioenergy breeding and population structure for association mapping, we selected 96 accessions and genotyped them with 95 simple sequence repeat markers. Subsequent genetic diversity and population structure analysis methods identified four subpopulations in this panel, which correlated well with the geographic locations where these accessions originated or were collected. Model comparisons for three quantitative traits revealed different levels of population structure effects on flowering time, plant height, and brix. Our results suggest that diverse germplasm accessions curated from different geographical regions should be considered for plant breeding programs to develop sweet sorghum cultivars or hybrids, and that this sweet sorghum panel can be further explored for association mapping.

Evaluation of Public Sweet Sorghum A-Lines for Use in Hybrid Production

“…Results of this study indicate that improvements can be made that will lead to useful sweet sorghum hybrids. Overall, there is significant sweet sorghum genetic diversity [8,9], whose genetic potential was not captured in this study which included six sweet sorghum cultivars, three of which were in common with one previous study [9] and five were in common with another previous study [8].…”

“…There have been recent studies examining the genetic relationships and diversity within the sweet sorghum collections [8,9]. However, it will be important to use grain sorghum lines as male sterile A-lines for sufficient production of hybrid seed, and if additive genetic effects control sugar content the A-lines should have genes for free sugars.…”

A first insight into population structure and linkage disequilibrium in the US peanut minicore collection

“…Five independent runs of the program were carried out for a 'K' value ranging from 1 to 10, with 50,000 burn-in time and 100,000 iterations, assuming an admixture model with correlated allele frequencies (Falush et al 2003;Pritchard and Wen 2004;Falush et al 2007). Further, the program was also run ten times for each 'K' value, ranging from 1 to 10, using the admixture model with correlated allele frequencies, with 20,000 replicates for burn-in and 10,000 replicates during analysis (Wang et al 2009). Values of k were also tested using methods in Evanno et al (2005).…”

Climatic adaptation and ecological descriptors of wild beans from Mexico

“…Agroecological characterization of wild/cultivated niches helps to determine the environmental requirements of a species, providing information on the adaptability and degree of tolerance to specific ecological conditions (Maxted, Dulloo, & Ford‐Lloyd, 2016; Pliscoff & Fuentes‐Castillo, 2011; Svenning, Fløjgaard, Marske, Nógues‐Bravo, & Normand, 2011; Wang et al., 2009). Ecological descriptors are environmental data from collection sites obtained after the standardization of map and layer construction using geographical information systems (GIS) (Cuervo‐Robayo et al., 2014; Suárez‐Venero, Soto‐Carreño, Garea‐Llanos, & Solano‐Ojeda, 2015; Wang et al., 2015).…”