Mycorrhizal inoculation and nitrogen fertilization affect the physiology and growth of spring wheat under two contrasting water regimes

Abstract

Aims Most plants benefit from mycorrhizal symbiosis through their improved abilities to take up nutrients and water. Information on the interactive effects of fungal inoculation, nitrogen (N) fertilization and drought on water use efficiency (WUE) and productivity of Canadian wheat varieties is scanty. Methods In this study, we investigated the effects of arbuscular mycorrhizal fungi (AMF) inoculation, N fertilization and water regime (well-watered (WW) vs water-deficit (WD)) on WUE, phosphorus (P) and N uptake and growth of spring wheat (Triticum aestivum var. Superb) in a greenhouse experiment. Results The specific leaf area (SLA) of flag leaves was significantly increased by AMF inoculation under the two water regimes but was lowered under N fertilization and drought conditions. The AMF inoculation significantly enhanced relative water content under WD. The WUE and instantaneous WUE (WUEi) were enhanced by N fertilization and AMF inoculation under both water regimes. Combined N fertilization and AMF inoculation significantly increased N concentrations in stem and grain, plant height, biomass and grain yield under WD. The P concentrations in stem and grain were increased under WD, irrespective of other treatments applied. The WUE and grain N, stem N, and P concentrations were positively correlated. Conclusions Plant physiological characteristics were negatively affected by WD, while N fertilization and AMF inoculation enhanced plant performance under WD, including the increase of N and P concentrations in different componments of spring wheat.

Stoichiometric N:P flexibility and mycorrhizal symbiosis favour plant resistance against drought

“…Previous studies also demonstrated that the degree of mycorrhizal symbiosis is intimately linked to plant water‐use efficiency (WUE; Querejeta et al . ; Zhang, Chang & Anyia ). WUE is defined as the amount of C acquired per unit of water transpired, reflecting the trade‐off between C gain and water loss.…”

“…; Hobbie & Colpaert ) and herbaceous species (Al‐Karaki ; Omirou, Ioannides & Ehaliotis ; Zhao et al . ; Zhang, Chang & Anyia ). Beneficial associations with AM fungi might explain the resistance of subordinate species to drought but this has not been directly tested.…”

“…Fungi are known to tolerate water stress (de Vries et al 2012;Barnard, Osborne & Firestone 2013) and root colonization by AM fungi often increases under drought (Aug e 2001), thus benefiting the survival and growth of the host plant (Worchel, Giauque & Kivlin 2013). Previous studies also demonstrated that the degree of mycorrhizal symbiosis is intimately linked to plant water-use efficiency (WUE; Querejeta et al 2003;Zhang, Chang & Anyia 2016). WUE is defined as the amount of C acquired per unit of water transpired, reflecting the trade-off between C gain and water loss.…”

“…WUE is defined as the amount of C acquired per unit of water transpired, reflecting the trade-off between C gain and water loss. Increasing WUE is one of the main attributes allowing plants to cope with drought, and mycorrhizal plants have been shown to increase their WUE more than nonmycorrhizal plants, in both trees Hobbie & Colpaert 2004) and herbaceous species (Al-Karaki 1998;Omirou, Ioannides & Ehaliotis 2013;Zhao et al 2015;Zhang, Chang & Anyia 2016). Beneficial associations with AM fungi might explain the resistance of subordinate species to drought but this has not been directly tested.…”

Alleviation of Drought Stress in White Clover after Inoculation with Arbuscular Mycorrhizal Fungi

“…Drought stress (DS), one of most predominant abiotic stresses, often results in an evident decrease in crop productivity and growth throughout the world (Zhang et al, 2016). Drought stress causes the damage to net photosynthetic behavior, electron transport system, and oxidative burst (Saraswathi and Paliwal, 2011).…”