Evaluation of Drought‐Related Traits and Screening Methods at Different Developmental Stages in Spring Barley

Abstract

Despite intensive research and breeding efforts, the physiological and quantitative genetic bases of drought tolerance are still poorly understood. The comparison of results obtained from different sources is also complex, because different testing methods may lead to controversial conclusions. This report discusses various drought stress experiments (hydroponics and in soil) in which the plant tolerance was studied at different developmental stages. Tests were performed in the germination, seedling and adult plant stages on the parental lines of five well‐known barley‐mapping populations. The results suggest that drought tolerance is a stage‐specific trait and changes during the life cycle. The effect of drought stress depended not only on the duration and intensity of water deficiency, but also on the developmental phase in which it began. To induce the same type of stress and to obtain comparable tolerance information from the replications, it is recommended that drought stress should be induced at the same growth stage. Correlations between the traits, commonly associated with improved drought resistance (high relative water content under stress, proline accumulation, osmoregulation) with stress tolerance indexes, are also presented, while the advantages and disadvantages of the most frequently used screening methods are discussed.

Dissecting the Phenotypic Components of Crop Plant Growth and Drought Responses Based on High-Throughput Image Analysis

“…Impact of drought depends heavily on timing and intensity of the dry period and on environmental conditions (Calderini et al, 2001;Araus et al, 2002) hampering heritability as a prerequisite for genetic mapping of quantitative trait loci (QTL) (Ribaut et al, 1997;Painawadee et al, 2009;Sellammal et al, 2014). Drought tolerance has been investigated in various QTL studies since the start of the molecular marker age (Lilley et al, 1996;Xiong et al, 2006;Szira et al, 2008;Nezhad et al, 2012). Adequate controlled phenotyping and daily phenotypic observation of drought stress development has a huge potential to boost the understanding of the genetics of drought tolerance.…”

Szárazságstressz hatása 22 árpafajta csíranövényének fotoszintetikus paramétereire = Drought-induced changes in photosynthetic parameters of seedlings of 22 barley cultivars

“…Vizsgálják a növények morfológiai (Bálint et al 2009, Jäger et al 2014, Skribanek és Tomcsányi, 2008, élettani paramétereit (Kerepesi és Galiba 2000, Sinha 2006, illetve genetikai adottságait. Például olyan, a menynyiségi jellegek kialakításában szerepet játszó géneket (Quantitative Trait Locus, QTL) keresnek, melyek összefüggésbe hozhatók a szárazságtűréssel (Szira 2008). A stressz kiváltására korábban főként a PEG vízelvonó képességét alkalmazták, azonban jelenleg elsősorban az ozmotikus stressz vizsgálatára alkalmazzák.…”

The Use of Hydroponics in Abiotic Stress Tolerance Research

“…There are, however, many reported discrepancies between research findings using hydroponics and soil-based systems. Recent studies in barley, for example, suggest that responses to salinity stress (Tavakkoli et al, 2010) and drought stress (Szira et al, 2008) can vary between hydroponics and soil culture. Assessments of P efficiency in wheat also differed greatly when cultivars were grown in hydroponics compared to soil (Hayes et al, 2004).…”