Mycorrhizal Treatments Research Articles

The Effectiveness of Endomycorrhiza Species on the Growth of Barangan Banana Seedlings

Utilization of various species of arbuscular mycorrhizal fungi in Barangan banana nurseries has been carried out in a wire house. The aim of the study was to obtain data on the effectiveness of Barangan banana seedling growth after various FMA species were applied. This research was conducted with a Completely Randomized Design with mycorrhizal (A) treatment consisting of 4 levels, namely: A0. Without mycorrhizae, A1. Glomus type 1; A2. Acaulospora type 4 and A3. Glomus fasciculatum (FMA isolate collection of Prof. Dr. Ir. Eti Farda Husin, MS) with 5 replications. A total of 10 g of FMA inoculants were separately put into the acclimatization media of the Barangan plantlet in the form of a sterilized charcoal and sand mixture (2: 1). during acclimatization. The results of this study indicate that seedling growth is better in the treatment of FMA applications than in controls. Acaulospora type-4 FMA isolates; Glomus type-1 and G. fasciculatum can increase the height of Barangan banana seedlings at a rate of: 3.117%; 2,831% and 2,328% while the rate of leaf growth is better in Glomus type-1 applications (1,865%), G. fasciculatum (1,709%) and Acaulospora type 4 (1,412 and control (1,174%).

BIOKONTROL ENDOMIKORIZA TERHADAP JAMUR Curvularia sp. PENYEBAB PENYAKIT TANAMAN JAGUNG (Zea mays L.)

In Indonesia, production of corn are used for fodder (55%), food (30%), and seed (15%). The growth of corn plants is limited by the presence of pests, weeds, and plant diseases. Curvularia sp. causing leaf spot and could decrease corn production. Use of mycorrhiza can be used as a biological agent in preventing pathogens outbreaks. Isolates of Curvularia sp. fungal was sprayed on corn seed. This research was conducted in laboratorium and green house. Corn seedlings were grown on sterile soil media (control), mycorrhizal treatments (100g of mycorrhizal + Curvularia sp., 200g of mycorrhizal + Curvularia sp., 300g of mycorrhizal + Curvularia sp.) and Curvularia sp. The observed variables were plant height, number of leaves, rate of disease progression, fresh weight and dry weight of plant canopy. The results showed that application of 100g inoculum tend to increase plant growth to 26-27% and percentage of mycorrhizal colonization to 58,66% thereof can decrease pathogen infection on plant at 28 day after planting.

Biological enhancement of mineral weathering by <i>Pinus</i> <i>sylvestris</i> seedlings – effects of plants, ectomycorrhizal fungi, and elevated CO<sub>2</sub>

Abstract. Better understanding and quantifying the relative influence of plants, associated mycorrhizal fungi, and abiotic factors such as elevated CO2 on biotic weathering is essential to constraining weathering estimates. We employed a column microcosm system to examine the effects of elevated CO2 and Pinus sylvestris seedlings, with or without the ectomycorrhizal fungi Piloderma fallax and Suillus variegatus, on rhizosphere soil solution concentrations of low-molecular-weight organic acids (LMWOAs) and on the weathering of primary minerals. Seedlings significantly increased mineral weathering, as estimated from elemental budgets of Ca, K, Mg, and Si. Elevated CO2 increased plant growth and LMWOA concentrations but had no effect on weathering. Colonization by ectomycorrhizal fungi, particularly P. fallax, showed some tendency to increase weathering. LMWOA concentrations correlated with seedling biomass across both CO2 and mycorrhizal treatments but not with total weathering. We conclude that nutrient uptake, which reduces transport limitation to weathering, is the primary mechanism by which plants enhanced weathering in this system. While the experimental system used departs from conditions in forest soils in a number of ways, these results are in line with weathering studies performed at the ecosystem, macrocosm, and microcosm scale, indicating that nutrient uptake by plants and microbes is an important biological mechanism by which mineral weathering is enhanced.

Identification of microRNAS differentially regulated by water deficit in relation to mycorrhizal treatment in wheat.

Arbuscular mycorrhizal fungi (AMF) are soil microrganisms that establish symbiosis with plants positively influencing their resistance to abiotic stresses. The aim of this work was to identify wheat miRNAs differentially regulated by water deficit conditions in presence or absence of AMF treatment. Small RNA libraries were constructed for both leaf and root tissues considering four conditions: control (irrigated) or water deficit in presence/absence of mycorrhizal (AMF) treatment. A total of 12 miRNAs were significantly regulated by water deficit in leaves: five in absence and seven in presence of AMF treatment. In roots, three miRNAs were water deficit-modulated in absence of mycorrhizal treatment while six were regulated in presence of it. The most represented miRNA family was miR167 that was regulated by water deficit in both leaf and root tissues. Interestingly, miR827-5p was differentially regulated in leaves in the absence of mycorrhizal treatment while it was water deficit-modulated in roots irrespective of AMF treatment. In roots, water deficit repressed miR827-5p, miR394, miR6187, miR167e-3p, and miR9666b-3p affecting transcription, RNA synthesis, protein synthesis, and protein modifications. In leaves, mycorrhizae modulated miR5384-3p and miR156e-3p affecting trafficking and cell redox homeostasis. DNA replication and transcription regulation should be targeted by the repression of miR1432-5p and miR166h-3p. This work provided interesting insights into the post-transcriptional mechanisms of wheat responses to water deficit in relation to mycorrhizal symbiosis.

Pengaruh Pemberian Pupuk Kandang dan Mikoriza terhadap Pertumbuhan Tanaman Kelapa Sawit (Elaeis guineensis Jacq.) di Pembibitan Pre-Nursery

<h1>In the Indonesian economy, the oil palm commodity plays a pretty bright role because it serves as a source of foreign exchange. The need to develop technology in producing superior seeds. In this study discuss about the Influence of Giving Fertilizer and Mikoriza Against the Growth of Palm Oil Plants (Elaeis guineensis jacq.) In Pre-Nursery Nursery. This study aims to determine the effect of manure and mycorrhizal fertilization as well as its interaction on the growth of coconut plants in pre-nursery nurseries. The study was designed by Factorial Randomized Block Design consisting of 2 treatment factors. The first factor of treatment of manure (K) consisting of 4 levels, namely: K0 = 0 kg / polybag, K1 = 0.15 kg / polybag, K2 = 0.30 kg / polybag, and K3 = 0.45 kg/polybag. The second factor of mycorrhizal treatment (M) consisting of 4 levels, namely: M1 = 12.5 g/polybag, M2 = 25.0 g/polybag, M3 = 37.5 g / polybag. The results showed that the treatment of cow manure up to 0.45 kg/polybag can increase the height of seedlings, stem diameter, total leaf area, wet weight of seedlings and dry weight of seedlings, but did not affect the number of oil palm seedlings.Mikoriza treatment up to 37, 5 g / polybags can increase seed height, stem diameter, total leaf area, wet weight of seedlings and dry weight of seedlings, but have no significant effect on the number of oil palm seedlings. The interaction between cow manure and mycorrhiza had no effect on all parameters observed.</h1>

Mycorrhizal alfalfa and surfactant affect the uptake and dissipation of phenanthrene in soil

A greenhouse experiment was conducted to compare the effects of biosurfactant Rhamnopyranoside and chemical surfactant Triton X-100 on the uptake of phenanthrene by mycorrhizal alfalfa (Medicago sativa L.) and phenanthrene dissipation in soil. Mycorrhizal treatment led to a higher phenanthrene accumulation in alfalfa and enhanced phenanthrene dissipation from the treated soil compared with non-mycorrhizal control. Inoculation combined with Rhamnopyranoside application gave the highest phenanthrene removal rate of 85.50% from treated soil and highest phenanthrene accumulation in plants (2.92 μg in root and 1.58 μg in shoot per pot) among all treatments. Besides, such combination treatment resulted in the highest freeze-dried biomass of plant (4.13 g for root and 3.31 g for shoot per pot), suggesting low toxicity for this treatment. These observations indicate co-effects of Rhamnopyranoside and inoculation may have potential as a biotechnological approach for decontamination of soil contaminated with phenanthrene.

Variation in the Essential Oil Composition and Morphological Parameters of Thymus daenensis Clack. with Two Species of Mycorrhizal Fungi Under Water Deficit Conditions

To investigate the effects of arbuscular mycorrhizal fungi (AMF) and drought stress on essential oil (EO) and chemical composition of Thymus daenensis Clack, an experiment was conducted at Shahrekord, Iran in 2017.The experiment was arranged as a factorial pattern in a randomized complete design with three replications. Factors were consisted of four irrigation regimes and two inocula. The first factor included four irrigation regimes, consisted of well-watered (A: absence of stress), irrigation after depletion of 20-25 % of field capacity (FC) (L: low stress), irrigation after depletion of the 35-40 % of FC (M: mild stress) and irrigation after depletion of the 55-60 % of FC (S: severe stress). The second factor included two mycorrhizal fungus treatments, non-inoculation with AMF (C: control) and inoculation with AMF (M: Funneliformis mosseae, Rhizophagus intraradices). The results showed that use of AMF and water stress at low rate increase some morphological characters and these increases were more evident at root part. Application of AMF did not have any significant effects on EO but, low water stress had significant effects on it. Interaction of AMF and water stress at low rate showed increases on root mycorrhization but did not have any positive significant effect on EO. Separate application of AMF and water stress had significant effects on 16 and 18 components of EO, respectively. Interaction of AMF and water stress significantly affect on 16 EO components especially thymol and carvacrol, two important components of T. daenensis EO.

Phytoremedial Potential of Tagetes Erecta Under Mycorrhizal Inoculation in Heavy Metal Polluted Soil

Investigation of the growth of Tagetes erecta under different levels of contamination of Copper (Cu) and Lead (Pb) in the soil and effects of mycorrhizal species (Glomus mosseae) on Cu and Pb to identify hyperaccumulator plants in tropical environment that could be used in remediation of heavy metal from contaminated soils. It was a greenhouse experiment consisted of factorial combination of two heavy metal (Cu and Pb) treatments which were replicated three times in Complete Ramdomized Design (CRD) with two mycorrhizal (Glomus mosseae and non-mycorrhizal) treatments. Metal solutions of Cu and Pb at the concentrations of Cu are 0, 125, 250, 500, 1000 mg kg-1 and concentrations of Pb are 0, 25, 50, 75, 100 mg kg-1 were prepared using CuCl2 and PbCl2 soluble compounds respectively. Soil mycorrhizal inocula of Glomus mosseae was applied at the rate of 20 g per pot. Five seeds of Tagetes erecta were planted per pot and were thinned to two stands per pot at two weeks after planting. Pre- and post- soil tests were carried out to determine soil physical and chemical properties, using standard methods. At 12 Weeks After Planting (WAP), Tagetes erecta was harvested and analyzed for Copper and Lead uptake using Atomic Absorption Spectrophotometer. The data collected were analyzed using descriptive and inferential statistics. The results showed that Arbuscular Mycorrhizal Fungi enhanced the number of leaves, height and stem girth of Tagetes erecta in high concentration (1000 mg kg-1) of Cu contaminated soil. Glomus mosseae inoculation did not enhance the growth parameters of Tagetes erecta irrespective of the levels of Pb contamination Glomus mosseae inoculation significantly (p≤0.05) increased Cu uptake of Tagetes erecta at 500 mg kg-1 of Cu concentration of a polluted soil. In contaminated soil, containing 50 mg kg-1 Pb Glomus mosseae significantly (p≤0.05) increased Pb uptake in Tagetes erecta.

Control of Fusarium Disease in Onion with Plant Growth Promoting Rhizobacteria (PGPR) and Mycorrhizae and Its Effect on Growth and Yield of Onion

<p>The productivity of onion in Indonesia is generally low due to fusarium wilt disease. Biological controls can be applied using PGPR and Mycorrhizae. The purpose of this research was understand the interaction between PGPR and Mycorrhizal inoculation against fusarium wilt intensity as well as the growth and yield of onions. The isolation of <em>Fusarium oxysporum</em> f.sp <em>cepae</em> and PGPR, followed by the tests of PGPR inhibition ability, phosphate solvent and HCN compound productivity. The method used in the field was a completely randomized design (CRD) with 2 replications. Results showed that the combination of PGPR and mycorrhizae as a whole was unable to suppress <em>Fusarium</em> wilt disease, but had significant effect to postpone the incubation period (26,19 days after inoculation) and increase the growth and yield of onion compared to the onion plants infected with <em>Fusarium</em> but without the combined treatment of PGPR and mycorrhizae and the PGPR treatment and mycorrhizal treatment as single treatments; the application of mycorrhizae as the single factor had a very significant effect on the number of bulbs, but had no significant effect on the inhibition of fusarium wilt intensity as well as the growth and yield of onions.</p>

Relationship between chlorosis, photosynthesis and the nutrient content of plane trees in the presence of chemical and organic fertilizers

Chlorosis disorder is a major problem affecting the growth and physiological processes of many trees including plane trees (Platanus orientalis L.). This experiment was conducted to study the relationship between leaf chlorosis disorder and the nutritional status and some important physiological characteristics of plane trees. The experiment was arranged in a randomized complete block design with six replications and four treatments including control, manure (M), manure + fertilizer (20-5-10) (MF), and manure + fertilizer + mycorrhizal fungi (MFA) ( Glomus intraradices + G. mosseae) . The results showed that although all treatments significantly improved the nutrients content, soluble carbohydrates content, photosynthesis rate and chlorophyll content in the leaves, they mostly reached their peak in the mycorrhizal inoculated plants. Nitrogen (N), phosphorus (P) and zinc (Zn) were increased in the AMF amended trees compared to the control plants. The photosynthesis rate was enhanced by all the mixtures at least by 60% compared to the control. The most Chlorosis (17.5%) to the leaves recorded on the control plants, while leaf damage dropped to less than 2.9% at mycorrhizal treatment leading to the improved nutritional balance in the plane trees. The results proved the effectiveness of including mycorrhizal inoculation to the common fertilization practices to prevent leaf chlorosis in the plane trees.

Potential of wild annual legumes for mountain pasture restoration at two silvopastoral sites in southern Spain: promising species and soil-improvement techniques

This study evaluates the potential for pasture improvement and restoration at two silvopastoral sites. We used a total of 16 wild legume species under different management systems (rhizobial inoculation, mycorrhizal inoculation, sheep penning, and sheep penning with mycorrhizal inoculation), at two mountain sites in Sierra Nevada Natural Park (Granada, southern Spain). The first site, Soportujar, had higher soil fertility and rainfall than the second, Lanjaron. Forage yields in Soportujar ranged from 265 to 8970 kg DM ha−1, Vicia amphicarpa, Vicia monantha, Vicia disperma and Lathyrus clymenum being the most productive species. Mycorrhizal inoculation resulted in higher forage yields for Lens nigricans, V. disperma and Vicia lutea. Seed yields were low, ranging from 5.9 to 1234 kg ha−1. Forage yields in Lanjaron were lower, ranging from 46 to 1415 kg DM ha−1; and the most productive species were V. monantha, V. disperma, Lathyrus cicera and Medicago rigidula. Sheep penning alone and together with mycorrhizal treatment resulted in greater forage yields for most of the species studied, although differences were only significant for V. disperma, V. monantha and Lathyrus sphaericus. Seed yields ranged from 0.4 to 60 kg ha−1. In conclusion, we recommend V. monantha, V. disperma and L. cicera followed by V. amphicarpa and L. clymenum (in wetter more fertile sites) and M. rigidula (in drier sites), as they seem to be the best adapted to the pedoclimatic conditions of Sierra Nevada Natural Park. Increasing nutrients in the soil (by sheep penning) and promoting nutrient assimilation (by mycorrhizal inoculation) may be effective strategies for increasing pasture biomass in silvopastoral sites.

Arbuscular mycorrhizal fungi increase both concentrations and bioavilability of Zn in wheat (Triticum aestivum L) grain on Zn-spiked soils

Although winter wheat (Triticum aestivum L) are commonly colonized by arbuscular mycorrhizal fungi (AMF) under field conditions, the effects and related mechanisms of the fungi on concentrations and bioavailability of Zn in grain is still unclear. A pot trial was done to survey the influence of two species of AMF (Funneliformis mosseae BGC HEB02 and Rhizophagus intraradices BGC HEB07D) on grain yield, concentrations of phytic acid and Zn in winter wheat (T. aestivum cv. Xiaoyan22) in Zn-spiked soils under two levels of P application. The present study showed that mycorrhizal inoculation apparently improved P nutrition in wheat and significantly (p < 0.01) increased grain yield, especially under low soil P conditions. Increasing levels of P and Zn in soils significantly (p < 0.01) enhanced phytic acid concentrations in wheat grain, while inoculation of AM fungi had insignificant effect on grain phytic acid concentrations. Grain Zn concentrations under the mycorrhizal treatments were 1.13–2.76 times of those without inoculation, especially for R. intraradices. The present study revealed that concentrations and bioavailability of Zn in wheat grain can be significantly increased by inoculation of AMF, indicating the potential of AMF to cope with Zn deficiency for residents living on wheat as their staple food.

Arbuscular mycorrhizal fungi as biotechnology alternative to increase concentrate of secondary metabolites in Zea mays L.

Leaves of corn (Zea mays L.) produce secondary metabolism compounds characterizing them as an alternative source of animal food. Plants of this species establish mutualistic symbiosis with arbuscular mycorrhizal fungi (AMF) which provide an increase in the contents of bioactive compounds. These compounds have pharmacological properties and are important to the process of healing diseases. The objective of this paper was to establish whether the association of Z. mays with AMF increases the concentration of phenolic compounds in the leaves. After 70 days of growth, corn leaves were collected and their extract used for phytochemical analyses that included: soluble carbohydrates, proteins, phenols, flavonoids, and total tannins. Plants associated with Claroideoglomus etunicatum (W. N. Becker & Gerdemann) C. Walker & A. Schussler (UFPE 06), Acaulospora longula Spain & N. C. Schenck (UFPE 21) and Dentiscutata heterogama (T.H. Nicolson & Gerd.) Sieverd., F.A. de Souza & Oehl (UFPE 19) presented an increase in the concentration of soluble carbohydrates of 153.7%, 86.6%, and 79.1%, respectively, in relation to the control. Concentration of flavonoids was higher in plants inoculated with A. longula comparing with the control, while the concentrations of phenols, tannins, and total proteins in the mycorrhizal treatments did not differ from the control. Use of mycorrhizal technology may represent an alternative to enhance the content of some foliar metabolites in Z. mays leading to the production of phytomass with greater phytochemical and nutritional qualities.

Physiological Response of Three Grapevine Cultivars Grown In North-Western Poland to Mycorrhizal Fungi

West Pomerania (Poland) is located near the northern boundary of the range of viticulture (the coldest zone A). Unfavourable weather conditions can pose a serious threat to the cultivated vines. One of the treatments used to increase the tolerance of plants to abiotic and biotic stresses is inoculation with symbiotic soil microorganisms. This paper focuses on the influence of mycorrhization on the changes in soil microbiology, the degree of colonization of roots by mycorrhizal fungi, and on selected physiological parameters of three grapevine cultivars (‘Pinot Noir’ on SO4 rootstock, ‘Regent’ on 5BB rootstock, and ‘Rondo’ on 125AA rootstock). The applied inoculation had a stimulating effect on the colonization of roots by arbuscular mycorrhizal (AM) fungi, as evidenced by higher mycorrhizal frequency and intensity in the mycorrhized plants. The mycorrhizal treatment increased the intensity of CO2 assimilation and transpiration. Mycorrhization reduced the efficiency of photosynthetic water use and increased stomatal conductance for water in the grapevines tested. The mycorrhizal treatment did not affect the concentration of assimilation pigments in vine leaves. The mycorrhization of grapevines had no effect on the values of initial fluorescence, maximum fluorescence, the maximum potential efficiency of photochemical reaction in PS II, the size of the pool of reduced electron acceptors in PS II, nor on the value of the PS II vitality index.

Responses of photosynthesis-related parameters and chloroplast ultrastructure to atrazine in alfalfa (Medicago sativa L.) inoculated with arbuscular mycorrhizal fungi

Atrazine is an ingredient in photosynthesis-inhibiting herbicides and has been widely used to combat weeds in farmland. However, most atrazine that is applied fails to degrade in the soil and subsequently affects non-target plants. In this study, we investigated the influence of arbuscular mycorrhizal fungi (AMF), Funneliformis mosseae on the photosynthesis-related parameters, chlorophyll content, and chloroplast ultrastructure in alfalfa plants, some of which had been exposed to atrazine. Our results showed that the percentage of AMF hyphal colonization reached 91.23% 35 days after the alfalfa was planted, which suggests a symbiotic relationship between F. mosseae and alfalfa roots. F. mosseae alleviated the inhibition of net photosynthesis and stomatal function significantly in alfalfa exposed to atrazine for 24 h. A chlorophyll fluorescence analysis revealed that F. mosseae prevented a major reduction in the performance of photosystem II (PSII) photochemistry in the presence of atrazine, such as the relative decrease of Fv/Fm between the non-mycorrhizal and F. mosseae mycorrhizal treatments was 4.4% and 5.8% after 24 and 48 h of atrazine exposure time. However, F. mosseae has no significant alleviation on a sharp reduction in the chlorophyll a, chlorophyll b and carotenoid content in alfalfa exposed to atrazine. For the chloroplast ultrastructure in alfalfa exposed to atrazine, the number of both plastoglobules and partial granal stacks was greater in the presence of F. mosseae. In general, our results indicate that the F. mosseae inoculation was beneficial to sustain photosynthesis-related performance, such as net photosynthesis, stomatal conductance, the maximum quantum yield (Fv/Fm) and effective quantum yield (ΦPSII) of PSII photochemistry in alfalfa after exposure to atrazine, because the mycorrhizal alfalfa had a greater number of plastoglobules and granal stacks in the chloroplast, thereby enhancing its resistance to the oxidative damage induced by atrazine.

NITROGENOUS FERTILIZATION LEVELS AND ROOT MYCORRHIZAL COLONIZATION ON PLANT GROWTH AND PRODUCTIVITY IN WHEAT CROPS

In a two-year study (2002-2003), mycorrhizal treatments in conjunction with three nitrogen fertilization levels of 0, 50, 100 kg of N/hawere tested on durum wheat in continuous cropping. The study took place in the Province of Foggia, a semi-arid area of the Mediterranean Basin in southern Italy, with silty-clay soil classified as Typic Chromoxerert. Seeds of cultivar Simeto were inoculated at sowing, and a completely randomized block design with three replications with and without inoculation was adopted. Plant samples were taken during the vegetative cycle of the durum wheat, and the root mycorrhizal colonization was examined. In all treatments,the percentage of colonised root length was significantly higher in the inoculated plants than it was in the control. The plants inoculated and fertilized with 50 kg N/ha showed a significant increase in grain yield.

Tanggap Pertumbuhan dan Hasil Tomat yang Diinokulasi FMA dalam Pengendalian Fusarium (Fusarium oxysporum f.sp. lycopersici)

The Wilt in tomato plants is caused by Fusarium oxysporum sp. Lycopersici. Fusarium oxysporum is soil borne which causes considerable losses. FMA as a biological agent provides an alternative opportunity to control root diseases such as fusarium. The purpose of this study was to study the treatment of FMA inoculation which is appropriate while controlling the damage of tomato plants caused by fusarium. The research design used was the experimental method in Completely Randomized Design. The results showed that the treatment of mycorrhizae inoculated one week before planting and continued with fusarium inoculation at the time of planting showed good results in inducing the resistance of tomato plants to fusarium disease. This is evidenced by root colonization in tomato plants by 53% and the average intensity of attacks by 3.14%. The mycorrhizal treatment inoculated one week before planting and followed by fusarium inoculation at planting also showed good results in increasing the growth of tomato plants compared to other treatments applied by mycorrhiza.

English

English

Appropriate nonmycorrhizal controls in arbuscular mycorrhiza research: a microbiome perspective

Establishment of nonmycorrhizal controls is a "classic and recurrent theme" in mycorrhizal research. For decades, authors reported mycorrhizal plant growth/nutrition as compared to various nonmycorrhizal controls. In such studies, uncertainties remain about which nonmycorrhizal controls are most appropriate and, in particular, what effects the control inoculations have on substrate and root microbiomes. Here, different types of control and mycorrhizal inoculations were compared with respect to plant growth and nutrition, as well as the structure of root and substrate microbiomes, assessed by next-generation sequencing. We compared uninoculated ("absolute") control to inoculation with blank pot culture lacking arbuscular mycorrhizal fungi, filtrate of that blank inoculum, and filtrate of complex pot-produced mycorrhizal inoculum. Those treatments were compared to a standard mycorrhizal treatment, where the previously sterilized substrate was inoculated with complex pot-produced inoculum containing Rhizophagus irregularis SYM5. Besides this, monoxenically produced inoculum of the same fungus was applied either alone or in combination with blank inoculum. The results indicate that the presence of mycorrhizal fungus always resulted in stimulation of Andropogon gerardii plant biomass as well as in elevated phosphorus content of the plants. The microbial (bacterial and fungal) communities developing in the differently inoculated treatments, however, differed substantially from each other and no control could be obtained comparable with the treatment inoculated with complex mycorrhizal inoculum. Soil microorganisms with significant biological competences that could potentially contribute to the effects of the various inoculants on the plants were detected in roots and in plant cultivation substrate in some of the treatments.

Effects of mycorrhizal fungi inoculation and soil amendment with hydrogel on leaf anatomy, growth and physiology performance of olive plantlets under two contrasting water regimes

Abiotic stresses present a real environmental problem in agriculture field. In our paper, we examine the significance of arbuscular mycorrhizal fungi (AMF) and soil amendment with water retaining superpolymers (hydrogel) on growth and physiology performance of olive plantlets. Our experiment was carried out in nursery conditions, to test the impact of hydrogel (TH) and mycorrhizal fungi (TM), used individually or combined (THM), and compare them with non inoculated plants (TC), to understand and reduce the water stress damage in olive plantlets (cv. Chemlali). We also evaluate interactions between hydrogel, mycorrhizal treatments and water regimes. Results of mycorrhization (M%) show that roots colonized by Rhizophagus irregularis of well-watered plants were about 40.87%. In combined treatment (THM), M% was about 32.14%. Compared to TC treatment, TM treatment enhances significantly the dry weights of the whole plant under the two water regimes. The TM treatment had the highest relative water content (66.50%) and Chl (a + b) (0.83 mg g− 1) in stressed conditions. We found also that under water stress, the maximal quantum efficiency of the photosystem II measurements in leaves were significantly improved by 50.70% in TH treatment compared to control. For phenolic contents, TH treatment decreased significantly total phenols by 50.10% compared to TC. Our study gives evidence that the use of AMF and the hydrogel separately or in combination may enhance the capacity to avoid drought damages of olive plantlets and improve olive performances.