Arbuscular Mycorrhizal Colonization Enhances Biochemical Status and Mitigates Adverse Salt Effect on Two Legumes

Symbiotic association between arbuscular mycorrhizal (AM) species and host plant roots improves plant growth and protects them from several abiotic stress factors. In the present study, the effect of Glomus mosseae and Glomus fasciculatum as an individual inoculation and in combination was studied on two legumes (Glycine max and Cyamopsis tetragonoloba) under soil salinity stress gradient [1.04 (control) to 8.26 dS/m]. Individual and co-inoculation of both the AM fungi alleviated adverse salt effect, with improvement in plant dry weight matter and biochemical parameters. However, these two isolates worked better in combination with respect to higher accumulation of soluble carbohydrate, reducing sugar, protein, proline concentration etc. C. tetragonoloba showed better response as compared to G. max in relation to improvement in nutritional profile under salt stress after AM treatment. As compared to non-mycorrhizal counterparts, co-inoculation with G. mosseae and G. fasciculatum in C. tetragonoloba enhanced total chlorophyll (14.83% at soil salinity of 3.78 dS/m), soluble carbohydrate (17.26% at soil salinity of 5.94 dS/m), proline (8.79% at soil salinity of 3.78 dS/m) while exposed to different soil salinity levels. Also, co-colonization with both the isolates showed more root colonization (%) and may be responsible for the better effect in salt stress alleviation. Electrolyte leakage of mycorrhizal plants was lowered at soil salinity gradient of 2.10 to 8.26 dS/m and hence, maintained membrane stability. These two isolates can be utilized as bio-inoculant in alleviation of adverse salt effect in soil in association with the two test legume plants.

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Influence of drought and salt stress on the growth of young Populus nigra ‘Italica’ plants and associated mycorrhizal fungi and non-mycorrhizal fungal endophytes

New Forests ◽

10.1007/s11056-021-09879-6 ◽

2021 ◽

Author(s):

Magdalena Kulczyk-Skrzeszewska ◽

Barbara Kieliszewska-Rokicka

Keyword(s):

Salt Stress ◽

Soil Salinity ◽

Mycorrhizal Fungi ◽

Growth Parameters ◽

Fungal Endophytes ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Populus Nigra ◽

Stress Factors ◽

Symbiotic Associations

AbstractPopulus nigra ‘Italica’ (Lombardy poplar) is a breeding cultivar of black poplar, widely used as a street tree or windbreak, often exposed to salinity and limited water availability. Populus roots can develop dual mycorrhizal associations with ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) fungi, and with non-mycorrhizal fungal endophytes (FE). The symbiotic fungi may alleviate the effects of adverse environmental conditions. We investigated the performance (growth and symbiotic associations) of one-year-old Populus nigra ‘Italica’ grown from woody cuttings in soil from natural poplar habitat and subjected to water scarcity and soil salinity (50 mM NaCl, 150 mM NaCl, 250 mM NaCl). With increasing soil salinity, a decrease in the growth parameters of the aboveground parts of the poplar plantlets and their fine roots were found; however, the roots were more resistant to the stress factors analyzed than the shoots. ECMF, AMF, and non-mycorrhizal FE were all tolerant to increased salt levels in the soil, and the ECM abundance was significantly higher under conditions of mild salinity (50 mM NaCl, 150 mM NaCl) compared to the control plants and those treated with 250 mM NaCl. Our results indicated that enhanced soil salinity increased the content of sodium and chlorine in leaves, but did not affect significantly the concentrations potassium, magnesium, calcium, phosphorus, or nitrogen. Significant accumulation of proline in leaves suggest salt stress of P. nigra ‘Italica’ treated with 250 mM NaCl and contribution of proline to the plant defense reactions.

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Predicting mangrove forest dynamics across a soil salinity gradient using an individual-based vegetation model linked with plant hydraulics

10.5194/bg-2021-255 ◽

2021 ◽

Author(s):

Masaya Yoshikai ◽

Takashi Nakamura ◽

Rempei Suwa ◽

Sahadev Sharma ◽

Rene Rollon ◽

...

Keyword(s):

Salt Stress ◽

Soil Salinity ◽

Mangrove Forest ◽

Field Data ◽

Salinity Gradient ◽

Carbon Gain ◽

Mangrove Forests ◽

Bruguiera Gymnorrhiza ◽

Rhizophora Stylosa ◽

Plant Hydraulics

Abstract. In mangrove forests, soil salinity is one of the most significant environmental factors determining mangrove forest distribution and productivity as it limits plant water uptake and carbon gain. However, salinity control on mangrove productivity through plant hydraulics has not been investigated by existing mangrove models. Thus, we present a new individual-based model linked with plant hydraulics to incorporate physiological characterization of mangrove growth under salt stress. Plant hydraulics was associated with mangroves nutrient uptake and biomass allocation apart from water flux and carbon gain. The developed model was performed for two-coexisting species of Rhizophora stylosa and Bruguiera gymnorrhiza in a subtropical mangrove forest in Japan. The model predicted that the productivity of both species was affected by soil salinity through downregulation of stomatal conductance, while B. gymnorrhiza trees grow faster and suppress the growth of R. stylosa trees by shading that resulted in a B. gymnorrhiza-dominated forest under low soil salinity conditions (< 28 ‰). Alternatively, the increase in soil salinity significantly reduced the productivity of B. gymnorrhiza compared to R. stylosa, leading to an increase in biomass of R. stylosa despite the enhanced salt stress (> 30 ‰). These predicted patterns in forest structures across soil salinity gradient remarkably agreed with field data, highlighting the control of salinity on productivity and tree competition as factors that shape the mangrove forest structures. The model reproducibility of forest structures was also supported by the predicted self-thinning processes, which likewise agreed with field data. In addition, the mangroves morphological adjustment to increasing soil salinity – by decreasing transpiration and increasing hydraulic conductance – was reasonably predicted. Aside from the soil salinity, seasonal dynamics in atmospheric variables (solar radiation and temperature) was highlighted as factors influencing mangrove productivity in a subtropical region. The physiological principle-based improved model has the potential to be extended to other mangrove forests in various environmental settings, thus contributing to a better understanding of mangrove dynamics under future global climate change.

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Sensitivity and uncertainty analysis of the HYDRUS-1D model for root water uptake in saline soils

Crop and Pasture Science ◽

10.1071/cp17020 ◽

2018 ◽

Vol 69 (2) ◽

pp. 163 ◽

Cited By ~ 6

Author(s):

Wenzhi Zeng ◽

Guoqing Lei ◽

Yuanyuan Zha ◽

Yuanhao Fang ◽

Jingwei Wu ◽

...

Keyword(s):

Salt Stress ◽

Water Uptake ◽

Soil Salinity ◽

Root Water Uptake ◽

Stress Factors ◽

Saline Soils ◽

Growth Stages ◽

1D Model ◽

Maximum Root ◽

Hydrus 1D

A variance-based global sensitivity analysis (extended Fourier amplitude sensitivity test, EFAST) was applied to the Feddes module of the HYDRUS-1D model, and the sensitivity indices including both main and total effects of actual root water uptake (RWUa) to seven Feddes parameters were quantified at different growth stages of sunflower (Helianthus annuus L.): seedling, bud, flowering and maturity. The effects of soil salinity, climate conditions, and crop root growth on parameter sensitivity were explored by analysing three precipitation frequencies and two maximum root depths across four field locations with different soil salinity levels in China’s sunflower-growing regions. Uncertainties for RWUa were evaluated at four stages with varying Feddes parameters for different field locations, precipitation frequencies and maximum root depths. We found that the water stress factor concerning ceasing root water uptake (h4), and two salt stress factors ht and Sp, indicating the salinity threshold and the slope of the curve determining the fractional decline in root water uptake per unit increase in salinity below the threshold, respectively, were three most important Feddes parameters for RWUa estimation in HYDRUS-1D. In addition, the effects of soil salinity and precipitation frequencies were stronger than maximum root depth on the order of the parameters’ impacts on RWUa. Our study suggested that h1, h2, h3h, and h3l might be determined by an economical method (e.g. literature review) in saline soils with limited observations, but it is better to calibrate wilting point (h4) and salt stress parameters (ht and Sp) based on local measurements.

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The distribution and phenology of arbuscular mycorrhizae along an inland salinity gradient

Canadian Journal of Botany ◽

10.1139/b95-143 ◽

1995 ◽

Vol 73 (9) ◽

pp. 1318-1327 ◽

Cited By ~ 27

Author(s):

Perry C. Johnson-Green ◽

Norm C. Kenkel ◽

Thomas Booth

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Soil Salinity ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizae ◽

Salinity Gradient ◽

Arbuscular Mycorrhizal ◽

Early Spring ◽

Vegetation Zones ◽

Salt Pan ◽

June July

The distribution and seasonal patterns of arbuscular mycorrhizal fungi activity were studied in an inland boreal salt pan site in north-central Manitoba. Semipermanent study regions were set up in each of five vegetation zones along a continuous salinity gradient. Roots of Hordeum jubatum, Distichlis stricta, Agropyron trachycaulum, Sonchus arvensis, Spartina gracilis, and other species were collected from the study regions over six time periods: April, June, July, August, and October of 1991, and May of 1992. These roots were used to quantify mycorrhizal colonization, as well as arbuscule and vesicle formation. Arbuscular mycorrhizal fungi were prevalent in the three vegetation zones with lowest soil salinity, with > 40% of the observed root pieces colonized. Colonization was < 2% in the other two zones, where soil salinity was consistently greater throughout the growing season. The only common pattern in the phenology of mycorrhizal activity was a low level of activity in the early spring. Mycorrhizal activity in most plant species occurred at high levels throughout the summer and fall. Differences in patterns of activity appeared to be linked to differences in phenology of root growth, and not to edaphic differences among vegetation zones. Key words: Manitoba, arbuscules, fungi, gradient, mycorrhiza, phenology, salinity, vesicles.

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Studies on salt stress tolerance of citrus rootstock genotypes with arbuscular mycorrhizal fungi

Horticultural Science ◽

10.17221/3742-hortsci ◽

2011 ◽

Vol 33 (No. 2) ◽

pp. 70-76 ◽

Cited By ~ 41

Author(s):

A. A Murkute ◽

S. Sharma ◽

S. K Singh

Keyword(s):

Salt Stress ◽

Arbuscular Mycorrhizal Fungi ◽

Stress Tolerance ◽

Mycorrhizal Fungi ◽

Salinity Gradient ◽

Arbuscular Mycorrhizal ◽

Am Fungi ◽

Poncirus Trifoliata ◽

Physical Parameters ◽

Citrus Rootstock

Citrus is grouped under the salt sensitive crops. Mycorrhizal fungi, a symbiotic relationship between plant roots and beneficial fungi, are supposed to impart the stress tolerance in the host plants. The stress tolerance improved due to Arbuscular Mycorrhizal fungi (AM fungi) colonization can be attributed to enhanced mineral nutrition. In the present study the efforts are made to evaluate the effectiveness of AM fungi with two citrus genotypes under salt stress. Three-month-old seedlings of Karna Khatta (Citrus Karna) and Troyer Citrange (Poncirus trifoliata × Citrus sinensis) were inoculated with the indigenous soil based AM inocula (mixed strains). The salinity gradient was developed by frequent irrigation with NaCl (0, 50, 100, 150 mM w/v). The results indicated that all the physical parameters were affected with increasing salinity. The proline accumulation increased while the chlorophyll, calcium and magnesium contents decreased significantly with increasing salinity. In general, the decreased AM colonization did not show any significant effects under salt stress.  

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Alleviation of salt stress by arbuscular-mycorrhizal Glomus species in Lactuca sativa plants

Physiologia Plantarum ◽

10.1034/j.1399-3054.1996.980413.x ◽

1996 ◽

Vol 98 (4) ◽

pp. 767-772 ◽

Cited By ~ 4

Author(s):

J. M. Ruiz-Lozano ◽

R. Azcon ◽

M. Gomez

Keyword(s):

Salt Stress ◽

Lactuca Sativa ◽

Arbuscular Mycorrhizal ◽

Glomus Species

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Halotolerant Microbial Consortia for Sustainable Mitigation of Salinity Stress, Growth Promotion, and Mineral Uptake in Tomato Plants and Soil Nutrient Enrichment

Sustainability ◽

10.3390/su13158369 ◽

2021 ◽

Vol 13 (15) ◽

pp. 8369

Author(s):

Chintan Kapadia ◽

R. Z. Sayyed ◽

Hesham Ali El Enshasy ◽

Harihar Vaidya ◽

Deepshika Sharma ◽

...

Keyword(s):

Salt Stress ◽

Salinity Stress ◽

Dry Weight ◽

Stress Factors ◽

Microbial Consortia ◽

Soil Conditions ◽

Mineral Uptake ◽

Shoot Height ◽

Tomato Plants ◽

Secondary Roots

Salinity significantly impacts the growth, development, and reproductive biology of various crops such as vegetables. The cultivable area is reduced due to the accumulation of salts and chemicals currently in use and is not amenable to a large extent to avoid such abiotic stress factors. The addition of microbes enriches the soil without any adverse effects. The effects of microbial consortia comprising Bacillus sp., Delftia sp., Enterobacter sp., Achromobacter sp., was evaluated on the growth and mineral uptake in tomatoes (Solanum Lycopersicum L.) under salt stress and normal soil conditions. Salinity treatments comprising Ec 0, 2, 5, and 8 dS/m were established by mixing soil with seawater until the desired Ec was achieved. The seedlings were transplanted in the pots of the respective pH and were inoculated with microbial consortia. After sufficient growth, these seedlings were transplanted in soil seedling trays. The measurement of soil minerals such as Na, K, Ca, Mg, Cu, Mn, and pH and the Ec were evaluated and compared with the control 0 days, 15 days, and 35 days after inoculation. The results were found to be non-significant for the soil parameters. In the uninoculated seedlings’ (control) seedling trays, salt treatment significantly affected leaf, shoot, root dry weight, shoot height, number of secondary roots, chlorophyll, and mineral contents. While bacterized seedlings sown under saline soil significantly increased leaf (105.17%), shoot (105.62%), root (109.06%) dry weight, leaf number (75.68%), shoot length (92.95%), root length (146.14%), secondary roots (91.23%), and chlorophyll content (−61.49%) as compared to the control (without consortia). The Na and K intake were higher even in the presence of the microbes, but the beneficial effect of the microbe helps plants sustain in the saline environment. The inoculation of microbial consortia produced more secondary roots, which accumulate more minerals and transport substances to the different parts of the plant; thus, it produced higher biomass and growth. Results of the present study revealed that the treatment with microbial consortia could alleviate the deleterious effects of salinity stress and improve the growth of tomato plants under salinity stress. Microbial consortia appear to be the best alternative and cost-effective and sustainable approach for managing soil salinity and improving plant growth under salt stress conditions.

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Effect of co-inoculation with arbuscular mycorrhizal fungi and phosphate solubilizing fungi on nutrient uptake and photosynthesis of beach palm under salt stress environment

Scientific Reports ◽

10.1038/s41598-021-84284-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Xue-Ming Zai ◽

Jun-Jun Fan ◽

Zhen-Ping Hao ◽

Xing-Man Liu ◽

Wang-Xiang Zhang

Keyword(s):

Growth Rate ◽

Salt Stress ◽

Nutrient Uptake ◽

Mycorrhizal Fungus ◽

Arbuscular Mycorrhizal ◽

Maximum Efficiency ◽

Poor Growth ◽

Stress Environment ◽

Beach Plum ◽

Phosphate Solubilizing

AbstractBeach plum (Prunus maritima) is an ornamental plant, famous for its strong salt and drought stress tolerance. However, the poor growth rate of transplanted seedlings has seriously restricted its application in salinized soil. This study investigated the effects of inoculation with arbuscular mycorrhizal fungus (AMF), Funneliformis mosseae, and phosphate-solubilizing fungus (PSF), Apophysomyces spartima, on the growth, nutrient (N, P, and K) uptake, and photosynthesis of beach plum under saline (170 mM NaCl) and non-saline (0 mM NaCl) conditions. We aimed to find measures to increase the growth rate of beach plum in saline-alkali land and to understand the reasons for this increase. The results showed that salinization adversely affected colonization by AMF but positively increased PSF populations (increased by 33.9–93.3% over non-NaCl treatment). The dual application of AMF and PSF mitigated the effects of salt stress on all growth parameters and nutrient uptake, significantly for roots (dry weight and P and N contents increased by 91.0%, 68.9%, and 40%, respectively, over non-NaCl treatment). Salinization caused significant reductions in net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), and intercellular CO2 concentration (Ci) value, while inoculation with AMF and PSF inoculations significantly abated such reductions. The maximum efficiency of photosystem II (PSII) (Fv/Fm), the photochemical quenching coefficient (qP), and the nonphotochemical quenching (NPQ) values were affected little by inoculation with AMF, PSF, or both under non-NaCl treatments. However, plants inoculated with AMF and/or PSF had higher Fv/Fm, qP, and ФPSII values (increased by 72.5–188.1%) than the control under NaCl treatment, but not a higher NPQ value. We concluded that inoculation with AMF or PSF increased nutrient uptake and improved the gas-exchange and Chl fluorescence parameters of beach plum under salt stress environment. These effects could be strengthened by the combination of AMF and PSF, especially for nutrient uptake, root growth, and Pn, thereby alleviating the deleterious effects of NaCl stress on beach plum growth.

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