Mycorrhizal Symbiotic Efficiency on C3 and C4 Plants under Salinity Stress – A Meta-Analysis

Abstract

A wide range of C3 and C4 plant species could acclimatize and grow under the impact of salinity stress. Symbiotic relationship between plant roots and arbuscular mycorrhizal fungi (AMF) are widespread and are well known to ameliorate the influence of salinity stress on agro-ecosystem. In the present study, we sought to understand the phenomenon of variability on AMF symbiotic relationship on saline stress amelioration in C3 and C4 plants. Thus, the objective was to compare varied mycorrhizal symbiotic relationship between C3 and C4 plants in saline conditions. To accomplish the above mentioned objective, we conducted a random effects models meta-analysis across 60 published studies. An effect size was calculated as the difference in mycorrhizal responses between the AMF inoculated plants and its corresponding control under saline conditions. Responses were compared between (i) identity of AMF species and AMF inoculation, (ii) identity of host plants (C3 vs. C4) and plant functional groups, (iii) soil texture and level of salinity and (iv) experimental condition (greenhouse vs. field). Results indicate that both C3 and C4 plants under saline condition responded positively to AMF inoculation, thereby overcoming the predicted effects of symbiotic efficiency. Although C3 and C4 plants showed positive effects under low (EC < 4 ds/m) and high (>8 ds/m) saline conditions, C3 plants showed significant effects for mycorrhizal inoculation over C4 plants. Among the plant types, C4 annual and perennial plants, C4 herbs and C4 dicot had a significant effect over other counterparts. Between single and mixed AMF inoculants, single inoculants Rhizophagus irregularis had a positive effect on C3 plants whereas Funneliformis mosseae had a positive effect on C4 plants than other species. In all of the observed studies, mycorrhizal inoculation showed positive effects on shoot, root and total biomass, and in nitrogen, phosphorous and potassium (K) uptake. However, it showed negative effects in sodium (Na) uptake in both C3 and C4 plants. This influence, owing to mycorrhizal inoculation, was significantly higher in K uptake in C4 plants. For our analysis, we concluded that AMF-inoculated C4 plants showed more competitive K+ ions uptake than C3 plants. Therefore, maintenance of high cytosolic K+/Na+ ratio is a key feature of plant salt tolerance. Studies on the detailed mechanism for the selective transport of K in C3 and C4 mycorrhizal plants under salt stress is lacking, and this needs to be explored.

Meta-analysis of Lamiaceae and Euphorbiaceae medicinal plants inoculated with arbuscular mycorrhizal fungi

“…In addition, a higher amount of P accumulated by inoculated plants indicates that their production was increased by the presence of P (Augé et al, 2014). Chandrasekaran et al (2016) affirm that AMF-inoculated plants can uptake more P and other soil nutrients, improving their development conditions and biomass production (Silva et al, 2010;.Like this study, biomass production related to increased P levels on plant shoot was verified in the literature. Meta-analysis investigated the responses of leguminous species to rhizobia and AMFs, the interactive effects of plant microbial symbionts and the influence of AMF inoculation on plants grown in saline soils (Kaschuk et al, 2010;Larimer et al, 2010;Chandrasekaran et al, 2016).…”

“…Chandrasekaran et al (2016) affirm that AMF-inoculated plants can uptake more P and other soil nutrients, improving their development conditions and biomass production (Silva et al, 2010;.Like this study, biomass production related to increased P levels on plant shoot was verified in the literature. Meta-analysis investigated the responses of leguminous species to rhizobia and AMFs, the interactive effects of plant microbial symbionts and the influence of AMF inoculation on plants grown in saline soils (Kaschuk et al, 2010;Larimer et al, 2010;Chandrasekaran et al, 2016). Increases in plant growth, biomass production and nutrient uptake have been proven, suggesting that AMFs help plants supply their demand for P and improve their survival and production conditions (Chandrasekaran et al, 2016).…”

“…This finding is in line with the results of , who verified that root biomasses were greater than shoot biomasses of Salvia officinalis L. inoculated with AMFs. Souza et al (2013) verified that increased levels of P raised biomass production of Mentha piperita L. Although the increased P availability to the plant is a common condition in mycorrhizal plants (Chandrasekaran et al, 2016), Souza et al (2013) also observed that the highest levels of P caused decreasing increment in shoot biomass in contrast to increasing increment in root biomass.…”

“…Meta-analysis investigated the responses of leguminous species to rhizobia and AMFs, the interactive effects of plant microbial symbionts and the influence of AMF inoculation on plants grown in saline soils (Kaschuk et al, 2010;Larimer et al, 2010;Chandrasekaran et al, 2016). Increases in plant growth, biomass production and nutrient uptake have been proven, suggesting that AMFs help plants supply their demand for P and improve their survival and production conditions (Chandrasekaran et al, 2016).…”

Tomato Yield, Quality, Mineral Composition and Antioxidants as Affected by Beneficial Microorganisms Under Soil Salinity Induced by Balanced Nutrient Solutions

“…Though Juniper and Abbott [19] reported the negative effect of soil salinity excess on the growth of AMF hyphae, contrastingly, in research on tomato, cucumber and lettuce [20,21] as well as on olive, apple and Citrus trees [22][23][24], the plant performances under salt stress conditions were enhanced by AMF inoculation. Indeed, the latter fungi encourage salt tolerance in the colonized plants by increasing water and nutrient uptake, K + /Na + ratio, osmoregulators synthesis, photosynthesis rate, water use efficiency [20].…”