AMF Inoculation Research Articles

The Application of Arbuscular Mycorrhizal Fungi Reduced the Required Dose of Compound Fertilizer for Oil Palm (Elaeis Guineensis Jacq.) in Nursery

Arbuscular mycorrhizal fungi have the ability to increase nutrient availability for the plant as well as improve the soil quality. However, the effectiveness of AMF is affected by soil fertility. Therefore, this study was carried out to determine the best dose of compound fertilizer for oil palm seedlings with and without AMF application. The factorial experiment (2 × 5) with four replication was carried out with the first factor was AMF inoculation, consisting of 2 levels: without AMF inoculation (m0) and with AMF inoculation (m1). The second factor was compound fertilizer dose, consisting of 5 levels: 0 mg polybag-1 (f0), 250mg polybag-1 (f1), 500 mg polybag-1 (f2), 750 mg polybag-1 (f3), and 1000 mg polybag-1 (f4). The treatments were arranged in a randomized complete block design (RCBD). The data obtained were tested using analysis of variance and means separation tested using Least Significant Difference (LSD) at α 5%. The result showed that oil palm seedlings’ response towards AMF inoculation was influenced by the dose of compound fertilizer based on plant height, leaf surface area, shoot fresh weight, and shoot dry weight. The best dose of fertilizer compound for oil palm seedlings inoculated with AMF was 500 mg polybag-1, whereas without AMF inoculation was 1000 mg polybag-1. In other words, the AMF application reduced 50% of compound fertilizer needed for oil palm seedlings.

Effects of Arbuscular Mycorrhizal Inoculation by Indigenous Fungal Complexes on the Morpho-Physiological Behavior of Argania spinosa Subjected to Water Deficit Stress

Our objective is to test selected mycorrhizal complexes to verify the contribution of mycorrhizal symbiosis as a biological tool promoting the development of the argan tree under hostile conditions. In addition, this study aims to assess the impact of soil drought caused by stopping watering of young argan plants inoculated with strains of fungal complexes indigenous to the species in comparison to non-inoculated plants. Under conditions of water deficit stress, the most marked reductions in fresh and dry biomass were recorded in non-mycorrhizal plants. The most negative values of leaf water potential Ψf and Ψb were also noted in non-mycorrhizal plants. On the other hand, plants inoculated with mycorrhizal Bouyzakarne inoculum were relatively less affected by watering discontinuation compared to those inoculated with mycorrhizal Argana inoculum. Water stress caused a reduction in potassium and phosphorus content in the leaves and roots of all plants. However, mycorrhizal plants exhibited the highest P and K values compared to non-mycorrhizal ones. Therefore, mycorrhization compensates for the deficit in absorption of inorganic nutrients during drought. Sodium gradually decreased in the leaves but increased in the roots, and this delocalization of Na+ ions under water deficit stress resulted in higher concentrations in the roots than in the leaves of all plants. However, the mycorrhizal plants exhibited relatively lower values of root Na+ compared to the non-mycorrhizal controls. The water deficit reduced the content of chlorophyll a and b in the leaves and the chlorophyll a/b ratio in stressed plants. The lowest chlorophyll values were recorded in non-mycorrhizal plants. The levels of proline and soluble sugars in the leaves and roots of argan plants increased in all plants, especially with the extension of the duration of stress. However, proline accumulation was higher in mycorrhizal plants, with superiority in plants inoculated with the Bouyzakarne complex in comparison with that of Argana. In contrast, the accumulation of soluble sugars was higher in non-mycorrhizal plants than in mycorrhizal plants. We concluded that with a correct choice of the symbiotic fungi complexes, AMF inoculation biotechnology can benefit argan cultivation, especially under stressful conditions in arid regions with structural drought, where native Arbuscular mycorrhizal fungi levels are low.

Biocontrol of Fusarium root rot in squash using mycorrhizal fungi and antagonistic microorganisms

BackgroundThe study amid to investigate the influence of Trichoderma album, T. harzianum, T. koningii, Bacillus subtilis (EF1) and Pseudomonas fluorescens against Fusarium solani, the causal agent of root rot in squash under in vitro conditions. Field experiment was conducted to evaluate the effects of arbuscular mycorrhizal fungi i.e., (Glomus intraradices, G. monosporum, G. etunicatu, AMF) and T. harzianum (TZ) as well as B. subtilis (BS) either as individual or combined treatment against Fusarium root rot of squash in two successive seasons of study 2020 and 2021 using New Eskandrani cultivar.ResultsTrichoderma harzianum caused the greatest reduction in mycelial growth of F. solani (75.17%), followed by T. album and T. koningii. Amongst the tested 4 cultivars (Sakata, Galaxy, New Eskandrani H1 hybird, Hollr Queen F1 hybrid) in glasshouse, Hollr Queen was the most resistant to the infection of F. solani with survival rate (84.92%), whereas New Eskandrani c.v was the most susceptible. Results of filed experiments proved that the combined inoculation of AMF + TZ + BS, AMF + BS, AMF + TZ, TZ + BS resulted in significant elevation of total chlorophyll, carotenoids, free phenolic compounds, free amino acids, total protein as well as the antioxidative enzyme activities (i.e. Superoxide dismutase, Peroxidase and Polyphenol-oxidase) and contents of macro and micro elements. Results further showed that the combined treatments caused a significant decrease in disease severity in both seasons with subsequent significant increase of plant growth parameters as well as total fruit yield/plant and total fruit yield/feddan.ConclusionIt could be concluded that the combined inoculations of the tested bioagents proved to have potentials in control of Fusarium root rot but large scale field experiments should be conducted before any ultimate conclusion or recommendation was drawn.

Mycorrhizal Fungi Inoculation Improves Capparis spinosa’s Yield, Nutrient Uptake and Photosynthetic Efficiency under Water Deficit

Agricultural yields are under constant jeopardy as climate change and abiotic pressures spread worldwide. Using rhizospheric microbes as biostimulants/biofertilizers is one of the best ways to improve agro-agriculture in the face of these things. The purpose of this experiment was to investigate whether a native arbuscular mycorrhizal fungi inoculum (AMF-complex) might improve caper (Capparis spinosa) seedlings’ nutritional status, their morphological/growth performance and photosynthetic efficiency under water-deficit stress (WDS). Thus, caper plantlets inoculated with or without an AMF complex (+AMF and −AMF, respectively) were grown under three gradually increasing WDS regimes, i.e., 75, 50 and 25% of field capacity (FC). Overall, measurements of morphological traits, biomass production and nutrient uptake (particularly P, K+, Mg2+, Fe2+ and Zn2+) showed that mycorrhizal fungi inoculation increased these variables significantly, notably in moderate and severe WDS conditions. The increased WDS levels reduced the photochemical efficiency indices (Fv/Fm and Fv/Fo) in −AMF plants, while AMF-complex application significantly augmented these parameters. Furthermore, the photosynthetic pigments content was substantially higher in +AMF seedlings than −AMF controls at all the WDS levels. Favorably, at 25% FC, AMF-colonized plants produce approximately twice as many carotenoids as non-colonized ones. In conclusion, AMF inoculation seems to be a powerful eco-engineering strategy for improving the caper seedling growth rate and drought tolerance in harsh environments.

Fertilizers, Mycorrhizal Inoculation and Atrazine Interactions on Weed Biomass and Yield of Maize

The decline in soil fertility and poor weed management are the dominant limitation on the production of maize in Nigeria. Improving the efficiency of fertilizers through AMF inoculation and atrazine application may be a sustainable way to increase land productivity. Using completely randomised design with three replications, combinations of Organomineral Fertilizer (OF) at 0, 50, 100, 150 kg N/ha- and NPK 15-15-15 (400 kg/ha); Arbuscular Mycorrhizal Fungi (AMF, with and without); and atrazine (0, 1.5 kg a.i/ha) were evaluated in 30 kg pot experiment. Maize grain yield ranged from 0.07-101.20 g/plant. Sole applications of OF, AMF and atrazine increased maize growth and yield. Combining atrazine with AMF inoculation improved maize growth but significantly reduced grain yield (37.13 g/plant) compared to sole applications of AMF (75.13 g/plant) or atrazine (62.97 g/plant). The application of OF did not alter the AMF-atrazine interaction, except under NPK fertilizer application, where the interaction enhanced grain yield. All treatments involving atrazine produced lower total dry weed biomass. However, the total dry weed biomass produced across fertilizer applications increased non-significantly with AMF inoculation, while AMF colonization reduced with atrazine application. Therefore, combining 100 kg N/ha OF with AMF inoculation or atrazine was suggested under organomineral fertilizer application.

Dual Inoculation With Arbuscular Mycorrhizal Fungi and Phosphorus Solubilizing Fungi Synergistically Enhances the Mobilization and Plant Uptake of Phosphorus From Meat and Bone Meal

Phosphorus (P) is the second most important mineral nutrient for plant growth and plays a vital role in maintaining global food security. The natural phosphorus reserves [phosphate rock (PR)] are declining at an unprecedented rate, which will threaten the sustainable food supply in near future. Rendered animal byproducts such as meat and bone meal (MBM), could serve as a sustainable alternative to meet crop phosphorus demand. Even though nitrogen (N) from MBM is readily mineralized within a few days, >75% of the P in MBM is present as calcium phosphate that is sparingly available to plants. Thus, application of MBM with the aim of meeting crop N demand could result in buildup of P reserves in soil, which necessitates the need to improve the P mobilization from MBM to achieve higher plant P use efficiency. Here, we tested the potential of two microbial inoculum-arbuscular mycorrhizal fungi (AMF) and P solubilizing fungi (Penicillium bilaiae), in improving the mobilization of P from MBM and the subsequent P uptake by maize (Zea mays). Compared to the non-inoculated MBM control, the application of P. bilaiae increased the P mobilization from MBM by more than two-fold and decreased the content of calcium bound P in the soil by 26%. However, despite this mobilization, P. bilaiae did not increase the tissue content of P in maize. On the other hand, AMF inoculation with MBM increased the plant root, shoot biomass, and plant P uptake as compared to non-inoculated control, but did not decrease the calcium bound P fraction of the soil, indicating there was limited P mobilization. The simultaneous application of both AMF and P. bilaiae in association with MBM resulted in the highest tissue P uptake of maize with a concomitant decrease in the calcium bound P in the soil, indicating the complementary functional traits of AMF and P. bilaiae in plant P nutrition from MBM. Arbuscular mycorrhizal fungi inoculation with MBM also increased the plant photosynthesis rate (27%) and root phosphomonoesterase activity (40%), which signifies the AMF associated regulation of plant physiology. Collectively, our results demonstrate that P mobilization and uptake efficiency from MBM could be improved with the combined use of arbuscular mycorrhizal fungi and P. bilaiae.

Evaluation of Essential Oil Yield and Ecological Indices in the Intercropping of thyme (Thymus vulgaris L.) and soybean (Glycine max L.) with Application of Arbuscular Mycorrhizal Fungus

AbstractBackground and Objectives :In order to using sustainable agricultural methods and entering new species for increasing biodiversity, a field experiment performed to evaluate the effect of thyme (Thymus vulgaris L.) and soybean (Glycine max L.) with application of biofertilizer on the essential oil productivity, essential oil yield and ecological indices. Material and Methods: A field experiment was carried out as split split plot based on the randomized complete blocks design (RCBD) with 12 treatments and three replication at the faculty of Agriculture, University of Maragheh during 2019 growing season. The main factor was different planting patterns including thyme sole culture, soybean sole culture, intercropping of one row soybean+ one row thyme (1:1) and intercropping of two rows of soybean+ one row thyme (2:1). The sub plot and sub- sub plot factor were inoculation and non-inoculation of arbuscular mycorrhizal fungus and harvest time (first harvest and second harvest), respectively. Results: The results demonstrated that the highest dry yield of thyme (634.5 g.m-2) was achieved in the sole culture of plants with application of AMF. Also, the highest essential oil yield of thyme (9.45 g.m-2) was observed in the first harvest and intercropping ratio of 1:1. In addition, the essential oil yield and essential oil yield of thyme with AMF inoculation increased by 30.86 and 11.95% compared with control. Moreover, the highest ecological indices (LER, AHER, ATER and LUE) and monetary indices (IA, MAI and SPI) were achieved in the intercropping ratio of 1:1 with AMF application. Conclusion: The intercropping ratio of 1 row soybean+ 1 row thyme along with biofertilizer could be suggested to farmers for enhancing economic income and land use efficiency.

Arbuscular mycorrhizal inoculum coupled with organic substrate induces synergistic effects for soil quality changes, and rhizosphere microbiome structure in long-term monocropped cucumber planted soil

The integrated soil biological amendments of mycorrhizal inoculation and organic substrate can be additive, synergistic, or antagonistic under plant-soil-microbe interaction. Underlying mechanisms of associated soil quality changes and microbiota structure are, however, less understood. To probe into this, consecutive greenhouse experiments (2016–2018) were conducted to study the effects of mycorrhizal inoculum (AMF: Diversispora epigaea L.) and soil organic substrate (GS: garlic stalk) were used as single and combined applications. In this study, a high-throughput sequencing approach was used to evaluate the rhizosphere microbiome structure of bacteria in the replanted substrate of 7-years of continuous cucumber cropping. From the two years of treatment, we found that co-amended GS + AMF significantly altered the soil quality changes through increasing soil organic matter, soil nutrient contents, and enzyme activities. Our 16 S rRNA amplicon revealed a distinct impact on alpha diversity and bacterial community. The observed species richness index (OTUs, Chao1, and ACE) and community diversity index (Shannon) were increased due to GS-amended soil and GS + AMF inoculation, respectively. Soil amendments also had apparent effects by altering bacterial community compositions at the phylum level, which were mostly associated with the higher abundance of Proteobacteria, Planctomycetes, Gemmatimonadetes, Actinobacteria and Bacteroidetes. Furthermore, correlation analyses revealed that the soil pH and enzyme activities emerged as the major determinants of the key microbial attributes. Our results suggest that GS + AMF treatment can directly regulate the soil environmental attributes or induce compositional shifts of microbes in the continuous cucumber cropping substrates. However, their co-inoculation impact was the shift of the key soil-microbiota consortium. Therefore, the study provides new insight into ways that can reduce the adverse effect of continuous cropping stress and eco-friendly contribute to the stable and healthy micro-ecological development in protected cultivation.

Mycorrhiza stimulates Rhizobium infection in Paraserianthes falcataria (L.) I.C. Nielson under Hg contamination

Symbiosis of and AMF increase soybean production, but the information on the association between these microbes in Paraserianthes falcataria (L.) I.C. Nielson or ‘sengon’ under Hg contamination is limited. We observed P. falcataria inoculated with arbuscular mycorrhiza fungi (Glomus sp.) stimulate nodule formation under Hg contamination. The study was set up in a pot experiment in the growth chamber a the Hg concentration was adjusted to 50 ppm in soil medium. Inoculation of AMF stimulates nodule formation and increases P. falcataria tolerance to Hg. We isolated several bacteria from the rhizosphere belonging to Rhizobium group and others. Understanding the ecology of soil bacteria is important for Hg bioremediation using P. falcataria.

Arbuscular Mycorrhizal Fungus Stimulates Young Field-Grown Nectarine Trees

Although mycorrhizae applications have been widely used to improve the establishment and growth of agricultural crops, there have been no studies on their application in field-grown nectarine trees. In this work, a commercial arbuscular mycorrhizal fungus (AMF; Glomus iranicum var. tenuihypharum) was applied by means of fertigation to inoculate young “Flariba” nectarine trees grown in south-eastern Spain to evaluate its effect on plant water status, and vegetative and reproductive growth. Using minirhizotrons to measure the root dynamics over a complete growing season, revealed that AMF substantially increased root growth (51% increase compared with untreated trees), while no changes in plant water status or canopy development were noted. The productive response improved in inoculated trees, as demonstrated by a significantly higher yield, fruit size, number of fruits per tree and greater crop load efficiency values than in untreated trees. Given that the same amount of irrigation solution was applied in both treatments, the irrigation water use efficiency increased by 19.5% in AMF compared with untreated trees. The findings of this study suggest that a simple inoculation of AMF can be considered a good practice in semi-arid agro-systems to firmly establish efficient young nectarine trees and enhance their adaptation to field conditions.

Growth and p uptake of maize at various p levels under AMF inoculation and different planting methods

Growth and p uptake of maize at various p levels under AMF inoculation and different planting methods

Growth and p uptake of maize at various p levels under AMF inoculation and different planting methods

Growth and p uptake of maize at various p levels under AMF inoculation and different planting methods

Co-inoculation of Arbuscular Mycorrhizal Fungi and the Plant Growth-Promoting Rhizobacteria Improve Growth and Photosynthesis in Tobacco Under Drought Stress by Up-Regulating Antioxidant and Mineral Nutrition Metabolism.

Drought stress is a major environmental concern that limits crop growth on a large scale around the world. Significant efforts are required to overcome this issue in order to improve crop production. Therefore, the exciting role of beneficial microorganisms under stress conditions needs to be deeply explored. In this study, the role of two biotic entities, i.e., Arbuscular mycorrhizal fungi (AMF, Glomus versiforme) and plant growth-promoting rhizobacteria (PGPR, Bacillus methylotrophicus) inoculation in drought tolerance of tobacco (Nicotiana tabacum L.), was investigated. The present results showed that drought stress considerably reduced tobacco plant's growth and their physiological attributes. However, the plants co-inoculated with AMF and PGPR showed higher drought tolerance by bringing up significant improvement in the growth and biomass of tobacco plants. Moreover, the co-inoculation of AMF and PGPR considerably increased chlorophyll a, b, total chlorophylls, carotenoids, photosynthesis, and PSII efficiency by 96.99%, 76.90%, and 67.96% and 56.88%, 53.22%, and 33.43% under drought stress conditions, respectively. Furthermore, it was observed that drought stress enhanced lipid peroxidation and electrolyte leakage. However, the co-inoculation of AMF and PGPR reduced the electrolyte leakage and lipid peroxidation and significantly enhanced the accumulation of phenols and flavonoids by 57.85% and 71.74%. Similarly, the antioxidant enzymatic activity and the plant nutrition status were also considerably improved in co-inoculated plants under drought stress. Additionally, the AMF and PGPR inoculation also enhanced abscisic acid (ABA) and indole-3-acetic acid (IAA) concentrations by 67.71% and 54.41% in the shoots of tobacco plants. The current findings depicted that inoculation of AMF and PGPR (alone or in combination) enhanced the growth and mitigated the photosynthetic alteration with the consequent up-regulation of secondary metabolism, osmolyte accumulation, and antioxidant system.

Arbuscular mycorrhizal fungi alleviate salinity stress in peanut: Evidence from pot‐grown and field experiments

AbstractArbuscular mycorrhizal fungi (AMF) species are essential for sustainable agriculture of legume crops; however, the AMF response in legume crops, especially from the perspective of physiological and molecular mechanisms under salinity conditions, is largely unknown. In this study, peanut (Arachis hypogaea L.) seeds were inoculated with AMF to investigate its salinity stress alleviation effects using the pot‐grown and 2‐year field experiments. Seeds from two peanut cultivars (HY22 and HY25) were inoculated with AMF Rhizophagus irregularis SA and Funneliformis mosseae BEG95 (1:1), and the physiological and transcriptional responses were compared between the AMF‐inoculated and non‐inoculated peanut plants. Under the salinity stress, compared with the control samples, the AMF‐inoculated plants showed higher net photosynthetic rate, leaf relative water content (RWC), plant height, osmolyte accumulation, but lower leaf relative electrolyte conductivity (REC). Also, the malondialdehyde (MDA) concentration was reduced while the antioxidant enzymes such as superoxide dismutase (SOD), guaiacol peroxidase (G‐POD), catalase (CAT), and ascorbate peroxidase (APX) were activated. Furthermore, transcriptome data revealed that AMF potentially alleviates salt stress by regulating redox processes, cell wall assembly, cell growth, and other similar processes. In the 2‐year field experiment, AMF‐inoculated peanut seeds of HY22 and HY25 were cultivated in both non‐saline and saline soils. Under salinity conditions, AMF inoculation induced the total protein concentration by 11.11 and 2.32% in kernels and further increased the peanut pod yield by 21.83 and 21.89% in HY22 and HY25, respectively. In non‐saline soil too, AMF increased the peanut pod yield by 11.47 and 23.98% in HY22 and HY25, respectively. Taken together, these results strongly demonstrate that the combination of AMF Rhizophagus irregularis SA and Funneliformis mosseae BEG95 (1:1) can alleviate salinity stress in peanuts by improving plant growth, photosystem, and antioxidant system. Additionally, it increases the peanut pod yield under both normal and salinity conditions.

Influence of the seedlings emergence and initial growth of palmarosa (Cymbopogon martinii (Roxb.) Wats. var. Motia Burk) by arbuscular mycorrhizal fungi in soil salinity conditions

Emergence of virtuous and healthy seedlings of aromatic crops underneath salinity conditions will offer optimum plant populations in a per unit area with surplus crop productivity and monetary returns. Study was performed to work out the effect of seedling emergence, its growth and initiation of AMF colonization during nursery development in salt affected soil. The pot culture experiment was carried out using palmarosa (Cymbopogon martinii) cultivars (‘Tripta’, ‘PRC-1’ and ‘CIMAP-Harsh’) seed inoculated with arbuscular mycorrhizal fungi (AMF viz., Rhizophagus intraradices, Funneliformis mosseae, Glomus aggregatum and Rhizophagus fasciculatus). The results indicated that AMF inoculation significantly enhanced the seed emergence, shoot and root development and vigor indices (I and II). The R. intraradices was most effective in terms of improving seedlings emergence, fresh shoot and root weight and vigor indices with cultivar ‘Tripta’. The maximum percent root colonization was observed in R. intraradices treatment with cultivar ‘Tripta’ (36.33 %). Principal component analysis (PCA) showed a clear difference between most of the AMF spp. and palmarosa cultivars from each other’s. The variation was explained by PC-1 (75.81 %) and PC-2 (14.12 %) and this contributes in total biplot 89.93 %. Substantially, the performance of cultivar ‘Tripta’ and F. mosseae was found to be most suitable for growing healthy and disease-free seedlings with high rate of AMF colonization which amplify agricultural output with high economic returns under salt stress soils.

Effects of AMF inoculation and nitrogen application on nitrogen mineralization of coastal saline soil

Effects of AMF inoculation and nitrogen application on nitrogen mineralization of coastal saline soil

The comparative analysis of row proportions and the effect on nutrient status maize and soybean intercropping in sandy soil of North Lombok, Indonesia

Competition is the main problem of application intercropping cultivation in sandy soil, such as water absorption, nutrients, sunlight, and growing space. Plant density and distribution are the primary roles to consume nutrient supply in the sandy soil during intercropping. The study was aimed at determining the nutritional status of maize and soybean intercropping in the sandy soil areas of North Lombok, Indonesia. The experiment was performed at Akar-Akar village in Bayan district of North Lombok and was designed with Randomized Block Design and five treatments, i.e., P1 (2 rows of maize + 2 rows of soybean), P2 (3 rows of maize + 2 rows of soybean), P3 (3 rows of maize + 3 rows of soybean), P4 (4 rows of maize + 2 rows of soybean), P5 (4 rows of maize + 3 rows of soybean). Each treatment was replicated three times. The variables observed were the nutritional status of the soil (N-total and P availability) and nutrient uptake (N and P). The result shows that intercropping patterns of 3 rows of maize and soybean (P3) with the addition of 15 tons of cattle manure per hectare and the inoculation of AMF can increase the nutritional status of soil in nitrogen and phosphorus absorption of plants’ nutrients. It is recommended for farmers to obtain high yields using an intercropping pattern of three rows of maize and three rows of soybeans. This research recommended that nutrient improvement can be achieved by intercropping three rows of maize and three rows of soybean. Further research is needed on the response to yields of various varieties of maize and soybean intercropped on sandy soil.

Promotion of Zinc Tolerance, Acquisition and Translocation of Phosphorus in Mimosa pudica L. Mediated by Arbuscular Mycorrhizal Fungi.

Heavy metal contamination of soil is of increasing concern because of its potential risk to human health. In this study, two AMFs (Rhizophagus intraradices and Funneliformis mosseae) substantially increased the biomass of bashfulgrass in Zn-contaminated soil, even at Zn levels of up to 600mgkg-1. Zn uptake in R. intraradices- and F. mosseae-mycorrhizal bashfulgrass was increased by 40-fold and 7-fold, respectively, when plants grown in Zn-contaminated (400mgkg-1) soil. Elemental analysis showed that neither AMF had an effect on Zn concentration in plant tissues, including the roots and shoots. However, a significant increase of phosphorus (P) concentration was observed, suggesting the increased is from the improved use efficiency of soil nutrients by AMFs. Comparing the two AMFs, better growth performance with more biomass occurred with R. intraradices-inoculated bashfulgrass in Zn-contaminated soil. This is consistent with R. intraradices being more tolerant to Zn than F. mosseae, indicated by a higher colonization percentage in bashfulgrass roots. Taken together, our data indicate that AMFs possibly improve acquisition and translocation of P to promote increased biomass. Moreover, mycorrhiza did not enhance Zn accumulation in shoots and roots of bashfulgrass at the same Zn level. In the future, developing AMF (especially R. intraradices) inoculation of plants might be a desirable means of safe production of ornamentalplants in metal-polluted soil.

Revegetation of Critical Land with Gaharu (Aquilaria malaccensis) under Various Ameliorants Application

Rehabilitation of post-mining limestone soils is often a challenge due to a lack of nutrients and poor soil humus. The research aims to study the effect of various ameliorants on soil chemical properties, growth, and P uptake of gaharu plant (Aquilaria malaccensis) in post-mining limestone soil for revegetation of critical land. The research was conducted in a Completely Randomized Design with three replications. The treatments were P0 (Control, without ameliorant); P1 (Humic Acid, HA, 4 kg ha-1 ); P2 (Phosphate Rocks, PR, 350 kg ha-1 ); P3 (Vesicular Arbuscular Mycorrhizal Fungi, AMF, 500 spores plant-1 ); P4 (HA+AMF); P5 (PR+AMF); and P6 (HA+PR+AMF). Data were analyzed using ANOVA at 95% confidence level and continued with the LSD test. The use of various types of ameliorants (HA, RP, and AMF) significantly increased root length, root volume, wet and dry weight of roots, shoot wet and dry weight, and P uptake of gaharu tree. The best ameliorant in increasing gaharu tree growth was AMF (P3) treatment, and AMF combined with HA (P4) treatment. Thus, for revegetation of critical land, especially post-mining limestone land, using gaharu tree requires HA and AMF inoculation.

Evaluasi Pertumbuhan Bibit Aren (Arenga pinnata (Wurmb) Merr.) Terhadap Pemupukan P dan Inokulasi Fungi Mikoriza Arbuskula

Aren is one type of plant that has the potential to be developed because all parts of the plant can be used. Currently, the cultivation of sugar palm is still traditional and far less than other types of Arecaceae family. The research was conducted from August to October 2016 at the nursery site, and analysis of spore types and AMF colonization in the SEAMEO BIOTROP Bogor Silviculture Laboratory. This research was conducted on palm seedlings that were 19 months old. This study used a completely randomized design with 2 factors, namely P fertilization and AMF inoculation. The P fertilization factor has 2 levels, namely without P fertilization and given P fertilization. The inoculation factor for AMF consisted of 3 levels, namely without AMF inoculation, indigenous AMF, and my cover AMF. The results showed that P fertilization treatment and AMF inoculation did not significantly affect all observed variables, namely plants, number of leaf midribs, length of rachis, plant diameter, SPAD value, number of spores, and root colonization. There was 3 genus of spores, namely Acaulospora sp., Gigaspora sp., and Glomus sp., as well as 2 types of root infections in the form of hyphae and vesicles.