Grain Yield Potential Strategies in an Elite Wheat Double‐Haploid Population Grown in Contrasting Environments

Abstract

The understanding of ecophysiological basis of wheat (Triticum aestivum L.) grain yield potential provides a useful framework to complement conventional breeding aimed at achieving genetic gains. This study analyzed the ecophysiological performance of an elite wheat mapping population (105 double-haploid lines derived from two modern cultivars, Bacanora and Weebil, with similar phenology but different and stable combinations of grain number per area unit (GN) and grain weight (GW) resulting in high grain yield) grown in four contrasting high-yielding environments, to determine the most successful strategies to increase grain yield potential. Main effect of environment on grain yield was significant (p < 0.0001) but the genotypic component was larger than genotype × environment interaction (30%). A robust and positive relationship between grain yield and biomass production was observed across all environments (r 2 > 0.82, p < 0.0001), and relatively high harvest indexes were expressed (0.39-0.51). While GN was clearly the dominant numerical component in terms of association with grain yield (r 2 > 0.51, p < 0.0001), a wide range in both components (i.e., GN and GW) was observed across all environments. This population represents a valuable resource for prebreeding studies, as the transgressive segregation in physiological and numerical yield components in combination with favorable expression of all agronomic traits could allow a fine phenotyping and mapping to identify key traits and quantitative trait loci linked with grain yield.

Wheat grain number: Identification of favourable physiological traits in an elite doubled-haploid population

“…If the former is the main mechanism, potential grain weight would not be affected (Acreche et al, 2008); but in the second case, the achieved increase in GN would bring about compensations in grain weight; as the smaller the size of the fertile florets, the smaller the potential weight of the grains (Calderini et al, 2001). In the present study, average grain weight tended to be negatively associated with fruiting efficiency in both environments at the whole population level (r = −0.38, p < 0.01 in BA and r = −0.28, p < 0.01 in CO), but this relation did not affect grain yield which was driven by GN (García et al, 2013). In the same way, top DH lines showed a lower average grain weight than the parental lines (ca.…”

“…As the parental lines are high-yielding cultivars, the DH population phenotyped in this work represents the germplasm routinely used in a breeding program. In a previous study with this population, García et al (2013) highlighted that GN was the main determinant of grain yield and that it did not show association with flowering time or plant height across four contrasting environments. Similarly, in the present experiment, GN and its determining traits did not show a consistent association with flowering time or plant height in BA and CO separately as those relationships were not of the same sign (positive or negative) and significant across the two contrasting environments (Fig.…”

“…A detailed description and discussion of the phenotypic variability of this population in grain yield strategies across contrasting environments, including BA and CO, has been reported in García et al (2013). From this work, it is important to highlight some characteristics of the population performance which were similar in both environments.…”

“…The wheat population used in this work consisted of 105 DH lines derived from a cross between two well-adapted and high-yielding cultivars of spring wheat, Bacanora and Weebil, with similar phenology but consistently differing in yield components: Bacanora normally has more grains than Weebil, while the latter has heavier grains than Bacanora (García et al, 2013). The cross was carried out in CIMMYT (Mexico) and the DH lines, derived from F 1 using the maize cross method (Laurie and Bennett, 1988) (CO).…”

TRITICALE (x Triticosecale Wittmack): RENDIMIENTO Y SUS COMPONENTES EN UN AMBIENTE SEMIÁRIDO DE LA ARGENTINA

“…En la Argentina se ha destacado la alta correlación positiva del número de granos por unidad de superficie con el rendimiento (Fraschina et al, 2004;García et al, 2013). Sin embargo, la extensa región triguera argentina comprende ambientes de producción semiáridos, subhúmedos y húmedos, que permitirían una expresión distinta sobre el llenado de los granos (Fraschina et al, 2004), carácter del que se menciona plasticidad y variación importante (García et al, 2013). Las mismas particularidades son dables de esperar en el cultivo de triticale, cuya área de cultivo potencial es similar a la triguera.…”