QTL Associated with Yield in Three Backcross‐Derived Populations of Soybean

Abstract

Soybean [Glycine max (L.) Merrill] plant introductions (PIs) are potential sources of useful genes for breeding. We mapped quantitative trait loci (QTL) for yield and other agronomic traits, and determined QTL × environment (QTL × E) and epistatic interactions for yield in three backcross (BC) populations. The populations were developed using PIs as donor parents and ‘Beeson 80’, ‘Kenwood’, and ‘Lawrence’ as recurrent parents (RP). Sixty‐eight BC2F5‐derived lines in the Beeson 80 population, 74 BC1F5‐derived lines in the Kenwood population, and 94 BC3F2‐derived lines in the Lawrence population were tested along with the RP and checks in 2003 and 2004. Nineteen QTL for three other agronomic traits were identified, as well as 13 yield QTL. The yield‐increasing allele was from the PI parent for eight yield QTL. Yield‐increasing alleles were associated with delayed maturity for three yield QTL, and one allele was associated with increased lodging and plant height. All yield QTL mapped to regions where yield QTL have been reported previously. The significant QTL × E interaction was due to undetectable or weak QTL effects in some environments. Nine digenic interactions for yield were detected in the Kenwood population, and were mostly between loci exhibiting epistatic effects only. Our results support previous findings that the current elite North American soybean gene pool is more diverse than would have been predicted by the number of contributing ancestors.

QTL mapping for yield components and agronomic traits in a Brazilian soybean population

“…In the same region of the molecular marker Satt300, in LG A1, Chen et al (2007) mapped one QTL, which explained 12.56% of the variation in seeds weight per plant, with estimated additive effect of 7.1 g. Another QTL associated with yield in the region of the same marker was mapped by Guzman et al (2007), which explained 18% of the variation in yield, with estimated additive effect of 60 kg ha -1 . Another QTL for yield in the same region was reported by Palomeque et al (2009).…”

“…Moreover, at least six QTL have been reported for grain yield, specifically (Palomeque et al 2009, Sebastian et al 2010, Kim et al 2012, Fox et al 2015, besides the several QTL mapped for other grain yield components from different populations , Guzman et al 2007, Zhang et al 2010, Liu et al 2011, Liu et al 2013.…”

Mapeamento de QTLs para caracteres relacionados com a fixação biológica de nitrogênio (FBN) em soja

“…Com essa abordagem, tem-se buscado identificar QTLs para produtividade em materiais não adaptados (SMALLEY et al, 2004;GUZMAN et al, 2007;LI, PFEIFFER e CORNELIUS, 2008). Guzman et al (2007) mapearam treze QTLs em três populações de retrocruzamento e em oito desses QTLs o alelo favorável foi derivado do genitor doador (PIs), sendo cinco localizados nos GL A1, B2, C1, C2 e K, em regiões onde outros trabalhos também relatam QTLs para produtividade em pelo menos duas populações independentes. O QTL localizado no grupo C2 foi significativamente associado ao SSR Satt557 em três ambientes diferentes e explicou, em média, 20% da variação.…”

Resposta à seleção em duas populações de soja com diferentes proporções de cada genitor

“…Para isso, atualmente estão sendo identificados QTLs (Quantitative Trait Locus) no genoma da soja associados ao rendimento da cultura a fim de indicar a existência de alelos com potencial de incrementar ainda mais a produtividade em germoplasma elite e em germoplasma introduzido (GUZMAN et al, 2007). De acordo com Collard et al (2005), assumindo uma população com tamanho infinito, podemos calcular a proporção teórica do genoma recorrente (P gr ) depois de n gerações de retrocruzamento, pela seguinte expressão (eq.…”

“…11), isto é: (LARK et al, 1995;GUZMAN et al, 2007;PALOMEQUE et al, 2009;SAINT MARTIN et al, 2009;WANG et al, 2009 …”