Waterlogging tolerance in barley is associated with faster aerenchyma formation in adventitious roots

Abstract

Background and aims Plant adaptation to waterlogged conditions requires a set of morphological and physiological/biochemical changes. The formation of aerenchyma is one of the most crucial adaptive traits for waterlogging tolerance. Enzymatic scavenging may also potentially contribute to waterlogging tolerance by providing detoxification of reactive oxygen species (ROS). Methods Changes of root porosity (as an indicator of aerenchyma formation) and activities in leaves of four major antioxidant enzymes, γ-amino butyric acid (GABA) and lactic acid contents in roots were evaluated in six barley genotypes contrasting in waterlogging tolerance.Results Soil waterlogging caused significant increases in adventitious root porosity in all genotypes. Waterlogging-tolerant genotypes showed not only significantly higher adventitious root porosity than sensitive genotypes but also much faster development of aerenchyma. The greatest difference in adventitious root porosity among genotypes was observed after 7 days of Plant Soil waterlogging treatment. At the same time, antioxidant enzyme activities in leaves, GABA and lactic acid contents in roots did not correlate with waterlogging tolerance. Conclusions A faster formation of aerenchyma in adventitious roots is one of the key factors for waterlogging tolerance in barley. This protocol is recommended to be applied in future studies to identify molecular markers linked to this trait using appropriate mapping populations.

The major‐effect quantitative trait locus CsARN6.1 encodes an AAA ATPase domain‐containing protein that is associated with waterlogging stress tolerance by promoting adventitious root formation

“…The production of ARs is an important adaptive trait for waterlogging tolerance (Zhang et al, 2015;Steffens and Rasmussen, 2016). Adventitious roots are induced by waterlogging to channelize the transportation of air diffused in the stem portion to the root (Visser et al, 1996).…”

Leaf anatomical and biochemical adaptations in <em>Typha domingensis</em> Pers. ecotypes for salinity tolerance

“…Aerenchyma is a characteristic feature of Typha domingensis, as of many other hydrophytes of aquatic saline wetlands (Zhang et al 2015b). One of the most common effects of increasing stress tolerance was the formation of aerenchyma.…”

4-Aminobutyrate (GABA): a metabolite and signal with practical significance

“…After 1 d of salinity, malate but not citrate increases, whereas after 3 d of salinity, both 2-oxoglutarate and succinate accumulate, even though GABA presumably does not contribute directly to the succinate pool in this mutant (Renault et al 2010). Cold stress, as well as waterlogging, flooding and hypoxia, which simulate an O 2 deficit, cause the accumulation of both GABA and succinate, and occasionally citrate, fumarate and malate (Kaplan et al 2007;Rocha et al 2010;Komatsu et al 2011;Antonio et al 2016) (Fig. 2).…”

“…1). Indeed, evidence has shown that GHB accumulates with oligomycin inhibition of mitochondrial ATP synthase (Geisler et al 2012), as well as cold (Kaplan et al 2007) (Fig. 2) and various other abiotic stresses, including O 2 deficit, waterlogging, heat, drought and UV (Allan et al 2003(Allan et al , 2008(Allan et al , 2012Breitkreuz et al 2003;Fait et al 2005).…”