Confirmation of delayed canopy wilting QTLs from multiple soybean mapping populations

Abstract

QTLs for delayed canopy wilting from five soybean populations were projected onto the consensus map to identify eight QTL clusters that had QTLs from at least two independent populations. Quantitative trait loci (QTLs) for canopy wilting were identified in five recombinant inbred line (RIL) populations, 93705 KS4895 × Jackson, 08705 KS4895 × Jackson, KS4895 × PI 424140, A5959 × PI 416937, and Benning × PI 416937 in a total of 15 site-years. For most environments, heritability of canopy wilting ranged from 0.65 to 0.85 but was somewhat lower when averaged over environments. Putative QTLs were identified with composite interval mapping and/or multiple interval mapping methods in each population and positioned on the consensus map along with their 95% confidence intervals (CIs). We initially found nine QTL clusters with overlapping CIs on Gm02, Gm05, Gm11, Gm14, Gm17, and Gm19 identified from at least two different populations, but a simulation study indicated that the QTLs on Gm14 could be false positives. A QTL on Gm08 in the 93705 KS4895 × Jackson population co-segregated with a QTL for wilting published previously in a Kefeng1 × Nannong 1138-2 population, indicating that this may be an additional QTL cluster. Excluding the QTL cluster on Gm14, results of the simulation study indicated that the eight remaining QTL clusters and the QTL on Gm08 appeared to be authentic QTLs. QTL × year interactions indicated that QTLs were stable over years except for major QTLs on Gm11 and Gm19. The stability of QTLs located on seven clusters indicates that they are possible candidates for use in marker-assisted selection.

Aerial canopy temperature differences between fast‐ and slow‐wilting soya bean genotypes

“…The paternal parent of the breeding lines in this research (PI 416937) is slow‐wilting (Abdel‐Haleem et al., ; Hwang et al., ; King et al., ) and has lower radiation use efficiency under water replete conditions relative to fast‐wilting genotypes (Ries et al., ). Consistent with this observation, the mechanism of slow‐wilting in PI 416937 has been attributed to conserving soil moisture prior to a drought (when moisture is abundant) and then drawing upon that moisture during a drought period when fast‐wilting genotypes have already depleted the soil moisture supply (King et al., ; Ries et al., ).…”

“…All relative canopy temperature measurements were made before R6 and before there would likely be large decreases in stomatal conductance and transpiration (Secor, Shibles, & Stewart, ) associated with phenology that would impact canopy temperature. Previous research demonstrated that the severity of wilting increases as plants approach maturity (Hwang et al., ). Therefore, it is important to consider possible maturity effects among genotypes as they approach maturity, and there is decreased stomatal conductance, transpiration (Secor et al., ; Wittenbach, Ackerson, Giaquinta, & Herbert, ) and evaporative cooling.…”

“…Soya bean genotypes differ in the beginning and severity of wilting in response to drought stress (King et al., ; Sloane et al., ). Canopy wilting has a broad‐sense heritability of around 0.60 and has been mapped in multiple populations (Abdel‐Haleem et al., ; Charlson et al., ; Hwang et al., , ). The slow‐wilting trait in soya bean has been found in several genotypes including PI 416937 (King et al., ; Sadok & Sinclair, ), PI 471938 (Fletcher, Sinclair, & Allen, ; King et al., ), PI 567690 (Pathan et al., ) and PI 567731 (Pathan et al., ).…”

Registration of ‘USDA‐N8002’ Soybean Cultivar with High Yield and Abiotic Stress Resistance Traits

“…Chen et al (2007) released two germplasm lines that exhibit improved N fixation during drought stress. Hussein et al (2011), Sinclair et al (2008), Charlson et al (2009), Fletcher et al (2007), Sadok and Sinclair (2010), and Hwang et al (2015) showed that the slow‐wilting trait is associated with multiple mechanisms of drought resistance, including response to atmospheric vapor pressure deficit (VPD), aquaporin activity, and rooting behavior, and genetic analyses have shown that as many as 10 quantitative trait loci (QTL) may be involved.…”

Evaluation of Methods for Estimating Transpiration Response to Soil Drying for Container‐Grown Plants

“…Genotypes evaluated were cultivar A5959, soybean accession PI 416937, and two recombinant inbred lines, 93705-34 and 93705-36, from a cross between cultivars KS4895 and Jackson (Charlson et al, 2009;Hwang et al, 2015). to progressive WD stress.…”