Assessment of 16 Peanut (Arachis hypogaea L.) CSSLs Derived from an Interspecific Cross for Yield and Yield Component Traits: QTL Validation

Abstract

Cultivated peanut is an allotetraploid (2n = 4× = 40) with narrow genetic diversity. In previous studies, we developed an advanced backcross quantitative trait loci (AB-QTL) population from the cross between the synthetic allotetraploid ((Arachis ipaensis × Arachis duranensis)4×) and the cultivated variety Fleur11, and mapped several quantitative trait loci (QTLs) involved in yield and yield components. We also developed a chromosome segment substitution line (CSSL) population as a way to mendelize the QTLs and analyzing their effects. In this study, 16 CSSLs were used for assessing the contribution of wild alleles in yield performance and stability across environments, as well as validating QTLs for pod and seed size. The CSSLs and the recurrent parent Fleur11, used as a check, were assessed using an alpha lattice design in three locations during two consecutive rainy seasons in Senegal, totaling six environments. Our results showed that the chromosome segments from the wild species, in general, have no yield disadvantage and contributed positive variation to yield-related traits. Most of the QTLs detected for pod and seed size in the AB-QTL on linkage groups A07, A08, A09, and B06 were also found in the CSSLs, showing that the CSSLs used in this study are accurate material for QTL validation. Several new QTLs have also been identified. Two CSSLs (12CS_031 and 12CS_069) showed consistently higher pod and seed size than Fleur11 in all environments, suggesting that the QTLs were consistent and stable. Our study opens the way for pyramiding these QTLs for peanut improvement.

Genetic and Environmental Variability, Heritability and Genetic Advance in Pod Yield, Yield Components, Oil and Protein Content of Peanut Varieties

“…The magnitude of the genotypic variance indicates that are significant variations within peanut varieties in terms of pod and seed weight and kernel ratio. High values of broadsense heritability were reported for seed weight (87-93%), 100-pod weight (88-91%), pod yield (71-74%) and 100kernel weight (87-96%) by Tossim et al (2020). Rao et al (2014) reported high heritability for shelling percentage (92.2%), pod number (76.9%), kernel weight (97.4%) and pod yield (95.5%).…”

Fine-Mapping of a Wild Genomic Region Involved in Pod and Seed Size Reduction on Chromosome A07 in Peanut (Arachis hypogaea L.)

“…The authors hypothesized these regions as a target of human selection during peanut domestication. More recently, using the CSSL population, Tossim et al [14] confirmed the QTL in the proximal region of chromosome A07 carried by the line 12CS_091 as involved in pod and seed size variation.…”

“…Genotypically, this CSSL differs from Fleur11 by the introgression of a segment of A. duranensis chromosome in the proximal region of the chromosome A07 relative to the published genome sequence. Phenotypically, it has smaller seeds than Fleur11 [14]. From these parents, a large F 2 population of 2172 individuals was developed by single cross followed by self-pollination of the F 1 generation.…”

“…The QTL involved in pod and seed size reduction was located in the proximal region of chromosome A07 between RN13D04 and TC23E04 SSR markers [12,14]. This segment is approximately 5 Mb size and is tagged by four markers (RN13D04, Seq2E06, Seq5D05 and TC23E04) [12,40].…”

Mapping of QTLs Associated with Biological Nitrogen Fixation Traits in Peanuts (Arachis hypogaea L.) Using an Interspecific Population Derived from the Cross between the Cultivated Species and Its Wild Ancestors

“…Advances in genetics and genomics offer opportunities to dive into feral peanut diversity to mine new alleles for breeding [ 35 , 36 ]. Interspecific mapping populations such as advanced backcross (AB-QTL) and chromosome segment substitution lines (CSSLs) were developed and used in peanuts to identify several QTLs related to yield components, disease resistance, oil quality, and plant morphology [ 37 , 38 , 39 , 40 ]. However, to our knowledge, interspecific mapping populations have not been exploited to investigate the effect of wild species alleles on BNF.…”