QTL analyses for tolerance to abiotic stresses in a common bean (Phaseolus vulgaris L.) population

Abstract

Common bean productivity is reduced by several abiotic stress factors like drought and low soil fertility, leading to yield losses particularly in low input smallholder farming systems in the tropics.To understand the genetics of stress tolerance, and to improve adaptation of common bean to adverse environments, the BAT 881 x G21212 population of 95 recombinant inbred lines (RILs) was evaluated under different abiotic stress conditions in 15 trials across four locations in Colombia, representing two higher altitude (Darién, Popayán) and two lower altitude (Palmira, Quilichao) locations. Stress vs non-stress treatments showed that yields were reduced in drought trials in Palmira by 13 and 31%, respectively, and observed yield reductions in low phosphorus stress were 39% in Quilichao, 16% in Popayán, and 71% in Darién, respectively. Yield components and biomass traits were also reduced. Traits linked to dry matter redistribution from stems, leaves and pods to seed, such as pod harvest index and total non-structural carbohydrates, were found to be important factors contributing to yield in all conditions. In contrast, early maturity was correlated with improved yield only in lower altitude locations, whereas in higher altitudes delayed maturity promoted yield. Superior RILs that combine stress tolerance and high cross-location productivity were identified. Lines that showed good yield under strong stress conditions also performed well under non-stress conditions, indicating that breeder’s selection can be applied for both conditions at the same time.Quantitative trait loci (QTL) analyses revealed a stable yield QTL on chromosome Pv04, detected individually in all locations, several stress treatments and in best linear unbiased predictions (BLUPs) across all trials. Furthermore, two QTL hotspots for maturity traits were identified on Pv01 and Pv08, which are the most stable QTL. The constitutive yield QTL could serve as a good candidate for marker development and could be used in marker assisted selection.Increased understanding of the physiology of abiotic stress tolerance, combined with the availability of superior germplasm and molecular tools, will aid breeding efforts for further improvement of these plant traits.

Effect of Water Deficit on Morphoagronomic and Physiological Traits of Common Bean Genotypes with Contrasting Drought Tolerance

“…Cultivars considered drought-tolerant can be used as parents to develop improved populations with a high frequency of favorable genes involved in water-deficit tolerance. In addition, the identification of genotypes with contrasting drought tolerance is important in the choice of parents for crosses, to establish segregating populations for future mapping of quantitative trait loci (QTL) [4,55,56].…”

Using Carbon Isotope Discrimination to Assess Genotypic Differences in Drought Resistance of Parental Lines of Common Bean

“…Drought‐resistant genotypes were selected based on deep rooting (BAT 477, SEA 5; Singh et al, 1990; White et al, 1990), high HI under drought (SER 16; Polania et al, 2016b), high shoot vigor under drought (SXB05; Assefa et al, 2013), drought and low‐fertility adaptation (BFS10; Beebe et al, 2008; Suarez‐Salazar et al, 2019), and genotypes described as drought resistant by CIAT due to their high yields under drought conditions (DAB 295, DAB 494; Polania et al, 2016b; Suarez‐Salazar et al, 2019). Drought‐sensitive lines were selected for their commercial use and known sensitivity to drought (Assefa et al, 2013; Polania et al, 2016a, 2017a; Diaz et al, 2018).…”

“…Researchers at the International Center for Tropical Agriculture (CIAT) select and develop drought‐resistant common bean varieties, with much of the selection having integrated grain yield and several morphophysiological traits such as pod harvest index (PHI), g s , deep rooting, and high vigor under drought (Beebe et al, 2013; Rao, 2014; Polania et al, 2016a, 2016b). Selected drought‐resistant germplasm was crossed with germplasm containing additional positive traits including seed composition and disease resistance, to develop improved cultivars and recombinant inbred line populations for genetic studies (Polania et al, 2016a; Diaz et al, 2018). However, the genotypic variation of Δ 13 C and its relationship to yield under conditions differing in water availability have not been studied in the parental lines of these CIAT mapping populations.…”

Breeding tepary bean (Phaseolus acutifolius) for drought adaptation: A review

“…For example, Diaz et al. (2018) identified two QTLs related to maturity on chromosome 1 and 8, and a yield QTL on chromosome 4 in common bean under drought stress. Dramadri et al (2019) identified 18 QTLs for phenology, yield components and partitioning traits (i.e., pod harvest index and pod partitioning index) on chromosomes 1, 2, 3, 4, 6 and 11 under drought stress and non‐stress conditions in Andean common bean gene pool.…”