Cell Membrane Stability and Association Mapping for Drought and Heat Tolerance in a Worldwide Wheat Collection

Abstract

Worldwide periods of heat and drought are projected to be more frequent, longer, and occurring earlier, which could deleteriously affect the productivity of cool-season crops including wheat (Triticum spp.). The coexistence of heat and drought stresses affects plant biochemical and physiological processes including cell membrane function. The increased permeability and leakage of ions out of the cell has been used as a measure of cell membrane stability (CMS) and as a screen test for stress tolerance. The main objectives of this research were to: (1) screen a global spring wheat panel for CMS by exposing leaf tissue to heat treatment and osmotic pressure (PEG 600), (2) identify potential quantitative trait loci (QTL)/genes linked with CMS using genome-wide association mapping, and (3) estimate the relationship between the field performance and measured CMS. The results indicated highly significant differences among the 2111 spring wheat accessions regarding CMS. Moreover, several SNPs were found to be significantly linked with CMS. The annotation of the significant SNPs indicated that most of these SNPs are linked with important functional genes, which control solute transport through the cell membrane and other plant biochemical activities related to abiotic stress tolerance. Overall, this study demonstrated the use of genome-wide association mapping for the identification of potentially new genomic regions associated with CMS. Tolerant genotypes identified in this study proved to be more productive under preliminary field stress conditions. Thus, the identified membrane-stable accessions could be used as parental genotypes in breeding programs for heat or drought stress tolerance.

Termotolerancia en líneas de sorgo [Sorghum bicolor (L.) Moench] para grano

“…Este parámetro es un indicador de la tolerancia al calor, por lo que valores bajos indican alta termoestabilidad de la membrana, mientras que valores altos indican baja termoestabilidad, lo que puede ser un criterio de selección indirecta para la tolerancia al calor (Blum et al, 2001;Morales et al, 2015). Así también, es uno de los rasgos secundarios que se utiliza para estudiar la sequía y el estrés por calor, ya que es un rasgo cuantitativo que es moderadamente heredable con una alta correlación genética con el rendimiento de grano, por lo que se utiliza ampliamente para seleccionar genotipos tolerantes (ElBasyoni et al, 2017).…”

“…La coexistencia de estrés por calor y sequía afecta los procesos bioquímicos y fisiológicos de las plantas, incluida la función de la membrana celular, por lo que el aumento de la permeabilidad y la fuga de los iones fuera de la célula, se han utilizado como una medida de la estabilidad de la membrana celular y como una prueba relacionada por tolerancia al estrés (ElBasyoni et al, 2017). La estabilidad térmica de la membrana puede ser un criterio de selección importante para la tolerancia al estrés por calor (Hemantaranjan et al, 2014) y el contenido relativo de agua es considerado un mecanismo de resistencia a la sequía (Ritchie et al, 1990).…”

Unraveling Field Crops Sensitivity to Heat Stress：Mechanisms, Approaches, and Future Prospects

“…Therefore, an electrolyte leakage value acts as a pointer of membrane injury and reflects stress-induced alterations and has been used to evaluate the thermostability of membranes under HS [66]. The increased permeability and leakage of ions out of the cell has been used as a measure of cell membrane stability and as a screen test for HS tolerance [67]. The effects of HS on membranes have been reported in various crops.…”

“…Similarly, in chickpeas, injury of the membrane was noticed at 40/30 • C, which was intensified at 45/35 • C, especially in sensitive genotypes [70]. A recent study investigated cell membrane stability under drought and heat conditions in wheat [67]. Membrane fluidity in temperature tolerance has been delineated by mutation analysis and transgenic and physiological studies.…”

QTL-Seq Identifies QTL for Relative Electrical Conductivity Associated with Heat Tolerance in Bottle Gourd (Lagenaria Siceraria)

“…There have been attempts to deconstruct stress tolerance into measurable components for accurate phenotyping, with the aim that QTLs associated with heat tolerance may then be identified and suitable alleles may be introgressed into elite genetic backgrounds [13]. Cell membrane stability, which has been used as an indicator of heat stress [14], may be quantified by relative electric conductivity (REC). REC is highly sensitive to abiotic stress [15] and has been used in studies of abiotic stress tolerance in a range of crops, including salinity-alkalinity tolerance in muskmelon [16], drought tolerance in Perennial ryegrass [17], and cold tolerance in alfalfa [18].…”