Response to flooding intensity in Elytrigia repens, E. intermedia (Poaceae: Triticeae) and their hybrid

Abstract

Summary Response to flooding intensity in three closely related taxa, Elytrigia repens, E. intermedia and their hybrid was studied. Plants were exposed to three intensities of flooding for a 30‐day period. Response to flooding intensity was estimated by measuring dry mass of the following: total biomass, above‐ground living biomass, above‐ground dead biomass, below‐ground biomass, rhizome and root mass and by the allocation of dry mass into rhizomes and root:shoot ratio. Reduction of nearly all the biomass compartments with increasing flooding intensity was observed in the three taxa. All three taxa can thus be regarded as flood‐intolerant. Based on the parameters measured, E. repens is regarded as the relatively most flooding‐tolerant, E. intermedia as the least tolerant, while the hybrid displayed intermediate flooding tolerance. The higher flooding tolerance in E. repens was likely related to its ability to accumulate a sufficient mass of rhizomes before flooding, due to higher regeneration ability. E. repens also displayed the highest phenotypic plasticity, as deduced from the reaction norms constructed for total biomass and rhizome mass of particular clones of the three taxa studied. This indicates that, on the species level, E. repens is better adapted to changing environmental conditions and it can be expected to colonize flooded soils. Both Elytrigia species also occur as weeds: E. intermedia grows in agricultural environments in warm regions, while E. repens infests many different types of habitats. Where they co‐occur, hybridization between them may lead to the enrichment of their gene pools with genes responsible for survival of the parental species under extreme conditions; their weedy potential may thus be enhanced.

The Invasive Wetland Plant Alternanthera philoxeroides Shows a Higher Tolerance to Waterlogging than Its Native Congener Alternanthera sessilis

“…However, waterlogging decreased the growth of these two species much less than that of flood-sensitive species [34]–[36], and even the 60 cm waterlogging treatment did not result in the death of any of the plants. Therefore, both species have a high capacity to tolerate waterlogging.…”

“…However, in the present study, the growth traits of A. philoxeroides were decreased less than those of A. sessilis under waterlogging conditions, indicating lower plasticity of growth traits (Table 1, Figures 1, 2 and 4). Previous studies generally showed that the negative impacts are greater in flood-sensitive plants than in flood-tolerant plants [23], [34], [38]. The flood-tolerant plants are often characterized by restricted growth performance and conservation of energy and carbohydrates, especially during complete flooding [24].…”

Natural hybridization between Elymus repens and E. hispidus assessed by AFLP analysis

“…Genotype integrity of this species is maintained in optimal habitats, while introgressed individuals are favoured in marginal habitats (Choler et al 2004). Studies on flooding tolerance of Elytrigia repens, E. intermedia and their hybrids have shown that hybridization may lead to the enrichment of hybrids gene pools with genes responsible for the survival of the parental species under extreme conditions (Mahelka 2006). CONCLUSIONS AFLP analyses and the level of pollen fertility unambiguously support the hybrid origin of Elymus ×mucronatus.…”

“…It appears that E. hispidus occurs primarily in the habitats studied, on the loess in Smoniowice and calcareous soils in Kielce. E. hispidus is adapted to a narrow range of environmental conditions and displays rather low phenotypic plasticity (Szczepaniak 2001;Mahelka 2006). The disturbance of agricultural activities in habitats on the field margins (in Smoniowice) and in the quarry neighbouring on a meadow (in Kielce) caused the disappearance of the more susceptible parental species E. hispidus and the spread of the better adapted hybrid specimens.…”

A Review of Non-Chemical Management of Couch Grass (Elymus repens)

“…Flooding tolerance of E. repens is expected, since it is a highly-adaptive species growing in a wide variety of habitats, including alluvial flooded meadows and periodically flooded habitats [156,157] together with the fact that plants with sufficient rhizome mass are able to survive oxygen deficiency ( [158] reported that E. repens survived a 50-day flood). However, longer flooding periods and long duration of anoxia in particular may be harmful to E. repens.…”