Mycorrhiza Treatment Research Articles

Effect of vermicompost and mycorrhiza fungi on yield and growth of milk thistle and antioxidant system activity.

In this study, the effect of vermicompost and mycorrhizal fungi was investigated on growth, yield, chlorophyll pigments, leaf antioxidant enzymes, and seed silibinin content of Silybum marianum, milk thistle. The seeds were inoculated by two species of mycorrhiza fungi, Glomus mosseae and G. intraradices, and plants were irrigated and treated with 0, 25, 50, and 75% vermicompost after culturing. The treated plants were then compared to control plants in a greenhouse experiment. The results showed that growth parameters including leaf area, and plant height and yield significantly increased in mycorrhiza fungi treated plants especially along with 75 % vermicompost treatment. The effects of symbiotic relationship between milk thistle and G. intraradices were more pronounced than G. mosseae. Moreover, combination of mycorrhiza and vermicompost increased the photosynthetic pigments chlorophyll (a), chlorophyll (b), total chlorophyll, and carotenoid. Also, a significant decrease was observed in activities of peroxidase, superoxide dismutase, and catalase after vermicompost and mycorrhiza treatment. The results showed that silibinin decreased significantly in vermicompost application.

Pengaruh Kascing dan Mikoriza terhadap Pertumbuhan dan Hasil Tribulus terrestris

Tribulus terrestris is one of the medicinal plants consumed in Indonesia that contain a variety of components. Saponins in Tribulus is an active component that can eliminate sexual dysfunction, improve erection function, protect the myocardium against ischemia/reperfusion injury and hypertension, and coronary heart disease. Various benefits contained in the Tribulus resulted in the tremendous opportunity to develop Tribulus in Indonesia. The reality in Indonesia is still very few farmers who develop Tribulus as the mainstay in planting, so that the yield and production of these plant are needed to meet market demand in Indonesia. It has prompted the need for proper cultivation and in accordance with the use of vermicompost fertilizer and mycorrhiza. This research aims to determine the effect of a dose of vermicompost and mycorrhiza on growth and yield of Tribulus. This research was conducted at the experimental farm of Faculty of Agriculture, Universitas Sebelas Maret in the village of Sukosari, Jumantono, Karanganyar. The research was conducted for three months, in June until August 2016. The design used in this research is a Completely Randomized Block Design (CRBD) arranged as factorial, consists of two factors of treatment with three experimental blocks. The first treatment factors that dose of vermicompost fertilizer consists of four levels: 0, 10, 20, 30 tonha-1. The second treatment factor is the dose of mycorrhiza consists of three levels: 0, 50, 100 sporesplant-1. The data were analyzed by F test or analysis of variants (Anova) continued with Duncan Multiple Range Test (DMRT) level of 5%. Mycorrhiza treatment dose of 100 sporesplant-1 gave the highest yield on the weight of the wet stover (844.63 g), time of the flowers appear (7 DAP), the number of branches (8 branchesplant-1), sum of fruit (627 fruits), and seed number (3,135 seeds). Mycorrhiza treatment dose of 50 sporesplant-1 gives the highest yield on plant height (167.8 cm). Meanwhile, vermicompost fertilizer treatment dose of 20 tonha-1 gives the best results on root volume (38.31 cm3). Keywords: medicinal plant, mycorrhiza, Tribulus terrestris, vermicompost.

THE ROLE OF BIOLOGICAL-FERTILIZER, PHOSPHATE ROCKS AND THE INTERACTION BETWEEN THEM ON THE PHOSPHOROUS AVAILABILITY IN SOIL AND PHOSPHOROUS UPTAKE BY CUCUMBER PLANT AND ITS EFFECT ON YIELD

A filed experiment was achieved in Abu-Ghraib during autumn season 2015 to test the activity of three types of biological fertilizer and phosphate rock as a sources of phosphorus. The treatments included ; Mycorrhiza mixed with phosphate rock, Bacillus mixed with phosphate rock, Mycorrhiza and Bacillus mixed with phosphate rock and phosphate rock alone. A 2% poultry decaying remnants was mixed to a 15 cm depth of soil and added before planting. Fertilizers was added according to the recommendations, and phosphate rock was added as a source of phosphorus. Result indicates that the treatment of the Mycorrhiza and Bacillus mixed with phosphate rock was the best in compared with other treatments. It gave about 12.96 mg P.kg-1 as an available phosphorus in soil, and about 0.3637% uptake phosphorus by the leaves of the plant, and about 3.943 k .ha-1 uptake phosphorus by vegetative part of the plant. The increasing of phosphorus supply of thin treatment as compared with the phosphate rock alone treatment were reached about 28.13, 23.41 and 91.40% for the phosphorus in soil, phosphorus in leaves and phosphorus in vegetative parts, respectively. Mycorrhiza treatment was in second order in compare to the to the residual treatments

Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L.) under different phosphorus application rates

In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L.) under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot), edible weight (84.36 g), dry weight (8.64 g) and leaf number (28) of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively) in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

THE EFFECT OF SALINITY PRETREATMENT OF GLOMUS MOSSEAE ON INDUCTION OF SALINITY TOLERANCE IN LYCOPERSICUM ESCULENTUM L.

Tomato (Lycpoersicum esculemtum) belongs to the Solanaceae potato family and is an important crop plant. It is relatively resistant to salinity, but in the saline environment growth and production of the plant significantly reduces. On the other hand, the presence of mycorrhiza fungus can improve the adverse effects of salinity. A factorial experiment in a completely randomized design with three replications was conducted on tomato plants in the Islamic Azad University. The first factor was mycorrhiza treatment with NaCl at 0 (control), 50, and 100 mM, and the second factor included salinity stress at 0 (control), 50, 100, and 200 mM. Based on the obtained results from variance analysis, the effects of mycorrhiza pretreatment with NaCl were significant on the root length. Also, the level of salinity pretreatment of mycorrhiza had a significant effect on proline content (p≤0.05). Moreover, salinity treatment had a significant effect on stem length, leaf area, the inoculation percentage of mycorrhiza, and proline content (p≤0.01) and on stem length (p≤0.05). Moreover, salinity pretreatment of mycorrhiza and salinity treatment reduced root length, the inoculation percentage of mycorrhiza, and proline accumulation. Salinity treatment reduced root length, leaf area, stem length, and the inoculation percentage of mycorrhiza while it increased proline content. Finally, it was found that salinity stress reduced the root length, stem length, leaf area, leaf water content, the inoculation percentage of mycorrhiza, potassium, phosphorous, and nitrogen while it increased the proline content. Finally, mycorrhiza pretreatment with NaCl was found to reduce the negative effects of salinity stress.

Microbial symbionts affect Pisum sativum proteome and metabolome under Didymella pinodes infection

The long cultivation of field pea led to an enormous diversity which, however, seems to hold just little resistance against the ascochyta blight disease complex. The potential of below ground microbial symbiosis to prime the immune system of Pisum for an upcoming pathogen attack has hitherto received little attention. This study investigates the effect of beneficial microbes on the leaf proteome and metabolome as well as phenotype characteristics of plants in various symbiont interactions (mycorrhiza, rhizobia, co-inoculation, non-symbiotic) after infestation by Didymella pinodes. In healthy plants, mycorrhiza and rhizobia induced changes in RNA metabolism and protein synthesis. Furthermore, metal handling and ROS dampening was affected in all mycorrhiza treatments. The co-inoculation caused the synthesis of stress related proteins with concomitant adjustment of proteins involved in lipid biosynthesis. The plant's disease infection response included hormonal adjustment, ROS scavenging as well as synthesis of proteins related to secondary metabolism. The regulation of the TCA, amino acid and secondary metabolism including the pisatin pathway, was most pronounced in rhizobia associated plants which had the lowest infection rate and the slowest disease progression. Biological significanceA most comprehensive study of the Pisum sativum proteome and metabolome infection response to Didymella pinodes is provided. Several distinct patterns of microbial symbioses on the plant metabolism are presented for the first time. Upon D. pinodes infection, rhizobial symbiosis revealed induced systemic resistance e.g. by an enhanced level of proteins involved in pisatin biosynthesis.

MINERAL UPTAKE AND DRY MATTER ACCUMULATION OF BIOTIZED GF677/'ROYAL GLORY' NURSERY PLANTS

The aim of this work is to study the influence of different mycorrhizal fungi and their further treatment in the nursery on plant mineral uptake and dry matter accumulation. Additional biotizations were preliminary done in some of the experimental treatments. The analysis of dry matter accumulation was performed twice in vegetation period (in May and October). Each sample was analyzed also for plant mineral uptake at six basic macro and microelements (N, P, K, Ca, Mg, Fe). Generally, all additional mycorrhiza treatments have a positive effect on the dry matter accumulation. In Trichoderma experimental plots highest increase is observed in Trichoderma (BS)(TG) and Trichoderma (SL)(TG) treatments, which showed more than 55% dry matter accumulation rates. For comparison, Trichoderma non-treated increase rate is less than 10%. Similar results are obtained in Glomus and Glomus+Agrobacterium treatments where additional treated plots overrun non treated ones with 21.1% and 82.7% respectively. Concerning the mineral uptake, additional mycorrhiza application show advantages in all treatments.

English

A field experiment was carried out to assess the effects of vesicular arbuscular mycorrhiza (VAM), Organo-mineral fertilizer (OMF) and NPK (15:15:15), on the performance and post-harvest quality of sweet corn. The experiment was laid out in a split plot design with mycorrhiza as main plot and fertilizer combinations as treatments. VAM inocula were applied at a rate of 888.88 kg ha-1, OMF at 2000 kg ha-1 and NPK (15:15:15) at 400kg ha-1. Storability of the sweet corn was evaluated at open shelf (25-27°C), normal refrigeration (40°C) and deep freezing conditions (0°C). Results showed that there were significant differences (p <0.05) between mycorrhiza and non mycorrhiza. Across mycorrhiza treatment, the highest yields of free corn ears were obtained with the complementary use of OMF and NPK (15:15:15). Fertilizer application had significant effect on the storage life of sweet corn, however, sweet corn stored by freezing at 0°C had the best storage properties in terms of firmness, weight loss and disease incidence.   Key words: Vesicular arbuscular mycorrhiza; sweetcorn yield; Organo-mineral fertilizer.

Response of Berseem Clover (Trifolium Alexandrinum L.) to Chemical, Biological and Integrated Use of Fertilizers

Abstract To evaluate the effect of different fertilizer types on the vegetative growth characteristics, yield and forage quality of berseem clover (Trifolium alexandrinum), the present experiment was conducted in Mahidasht Agriculture and Natural Resources Research Station (Kermanshah, Iran), during 2011 and 2012 growing seasons. The experimental treatments consisted of control (no fertilizer), chemical fertilizer, biological fertilizer and different combinations of chemical and biological fertilizing systems. A complete randomized block design with three replicates was employed for analysis of the data for each year. A combined analysis of variance was conducted to compare the data from the two years of the experiment. The results showed that the highest forage yield (172.1 g/m2) was produced in integrated fertilizer application (urea chemical fertilizer + mycorrhiza treatment). The highest crude protein content of 25% was obtained from integrated biological fertilizer treatment (nitrogen-fixing bacteria + phosphorussolubilizing bacteria treatment). The superiority of integrated fertilizer application for higher forage production and biological fertilizer application for higher forage quality in berseem clover could be recommended by the results of this experiment. Application of integrated fertilizing treatments not only optimized the chemical fertilizer application (consequently reducing the environmental pollutions), but it also enhanced forage quality in terms of higher macro a micronutrients concentrations. According to the results of this study it could be concluded that integrated fertilizing treatments may be accounted more efficient in dry farming than in irrigated agroecosystems.

Impact of Mycorrhiza Fungi from Grassland Rhizosphere and Liquid Organic Fertilizer to the Growth and Yield of Sweet Corn on Ultisols in South Konawe, Indonesia

This research was conducted in the Abenggi of village, District of Landono, Regency of South Konawe, Province of Southeast Sulawesi and Laboratory of the Faculty of Forestry and Environmental Science Halu Oleo University Kendari, Indonesia took place from November, 2014 untill April, 2015. This study aims to determine the effect of mycorrhiza fungi from granssland and liquid organic fertilizer to the growth and yield of sweet corn on Ultisols Abenggi. This research is compiled using a randomized block design (RBD) with factorial pattern. The first factor are mycorrhiza fungi (M) with three levels: without mycorrhiza fungi (M0), mycorrhiza as 20 g each planting hole (M1), mycorrhiza as 40 g each planting hole (M2) and second factor are liquid organic fertilizer (P) which comprises three levels of treatment: without liquid organic fertilizer (P0) liquid organic fertilizer as 50 ml L-1 water each plot (P1), liquid organic fertilizer as 100 ml L-1 water each plot (P2). The combination of these two factors obtained 9 combinations of each treatment was repeated three times in order to obtain the amount of 27 experimental units. The observed variables in this study were plant height, stem diameter, cob weight with husk, corn cob without husk, cob length, cob diameter, number and percentage of mycorrhiza infection on the roots of the sweet corn. The results showed that the interaction between mycorrhiza fungi and liquid organic fertilizer has a significant effect on the plant height age 42 days after planting and cob weight without husk with the best results obtained in the treatment of mycorrhiza as 40 g hole-1 with liquid organic fertilizer as 50 ml L-1 water. Application the mycorrhiza fungi as 40 g hole-1 gives the best results on the growth and yield of sweet corn.

Improving Wheat Yield and Quality through an Integrated Nutrient Management System

Abstract In order to evaluate the effect of different chemical and biological fertilizers on wheat ( Triticum aestivum L. cv. Pishtaz), this experiment was conducted in 2013 at the research field of Islamic Azad University, Karaj branch, Iran. The experiment was conducted in the form of a randomized complete block design (RCBD) with four replications and the eight following treatments: (1) control (without any fertilizer application), (2) urea + triple super phosphate, (3) urea + plant growth promoting rhizobacteria (PGPR), (4) urea + mycorrhiza, (5), urea + mycorrhiza + PGPR, (6) PGPR + triple super phosphate, (7) PGPR and (8) PGPR + mycorrhiza. At the end of the growth period, the following traits were measured: plant height, the number of tillers, 1000 kernels weight, grain yield, total biologic yield, protein content and the harvest index. Analysis of variance indicated that the treatments of the experiment had significant effect on all the measured traits at P≤0.01, except for the protein content which was not affected by the treatments. Mean comparison showed that nitrogen + PGPR + mycorrhiza treatment was the most effective treatment and resulted in the highest plant height (94 cm), the number of tillers (7.2), 1000 kernels weight (44.41 g), grain yield (8645.3 kg/ha) and biologic yield (19762.5). However, the harvest index was the highest in PGPR treatment (58.97). Results of this experiment reveled the effect of integrated nutrient management on wheat yield and quality.

Potential of Various Fungi for Biomass Production of Castor

An experiment was conducted to evaluate biomass production of castor (Ricinus communis) with inoculation of native Arbuscular Mycorrhizal Fungi (AMF), Trichoderma harzianum and Aspergillus niger. In castor, dual treatment of mycorrhiza and T. harzianum was better for shoot length (29.5 cm), root length (40.3 cm), fresh shoot weight (4.90 g), fresh root weight (1.13 g), number of leaves (10) and leaf area (75.5 cm2) than dual treatment of mycorrhiza and A. niger or mycorrhiza alone. These findings established the potential of the fungi for increase in biomass of castor.

Interaction between root growth allocation and mycorrhizal fungi in soil with patchy P distribution

Many plants preferentially grow roots into P-enriched soil patches, but little is known about how the presence of arbuscular mycorrhizal fungi (AMF) affects this response. Lotus japonicus (L.) was grown in a low-P soil with (a) no additional P, (b) homogeneous P (28 mg pot−1), (c) low heterogeneous P (9.3 mg pot−1), and (d) high heterogeneous P (28 mg pot−1). Each P treatment was combined with one of three mycorrhiza treatments: no mycorrhizae, Glomus intraradices, indigenous AMF. Real-time PCR was used to assess the abundance of G. intraradices and the indigeneous AMF G. mosseae and G. claroideum. Mycorrhization and P fertilization strongly increased plant growth. Homogeneous P supply enhanced growth in both mycorrhizal treatments, while heterogeneous P fertilization increased biomass production only in treatments with indigenous AMF inoculation. Preferential root allocation into P-enriched soil was significant only in absence of AMF. The abundance of AMF species was similar in P-enriched and unfertilized soil patches. Mycorrhization may completely override preferential root growth responses of plants to P- patchiness in soil. The advantage of this effect for the plants is to give roots more freedom to forage for other resources in demand for growth and to adapt to variable soil conditions.

EFFICIENCY OF ELEMENTAL SULFUR ON MYCORRHIZAE IN THE YIELD INCREASE OF WHEAT

Mycorrhizal infection enhances phosphorus (P) nutritional status of plants under P-deficient soil condition. The yield responses of wheat to sulfur (S) alone, phosphorus (P) alone, and combined application of sulfur and phosphorus in mycorrhizal and non-mycorrhizal treatments in calcareaous non-sterilized Karaburun soil (sub-group Typic Xerorthent) were investigated. The elemental sulfur enhanced the mycorrhizal efficiency that resulted in increased shoot, root, and grain yield dry matter in comparison to mycorrhiza treatment alone. This new finding to increase the efficiency of the mycorrhizae by the addition of 100 mg kg−1 elemental sulfur to the soil suggests that elemental sulfur may play an important role for the ecologic agriculture. It can be specifically important for increasing the efficiency of mycorrhizal infection in well-aerated P deficient soil.

THE EFFECT OF MYCORRHIZA GROWTH AND EXPRESSION OF SOME GENES IN BARLEY

Barley is one of the most important crops for food consumption. Soil fertilization using minerals and chemical compounds are not safe for human health beside beingas expensive. Therefore, It is important to find suitable alternatives. The arbuscular mycorrhiza (AM) is characterized by the formation of arbuscules (sometimes vesicles). The fungus occupies various proportions of the volume of host cells but is separated from the cell cytoplasm by the elaboration of the host plasma membrane forming a fungal membrane and an apoplectic compartment between the fungus and host cytoplasm. Mycorrhiza changes whatever source of phosphorus into phosphoric acid which acidifies the rhizosphere and thus increases the availability of elements for plants uptake. The increase of the availability of elements specially, calcium which plays the main role in cell signaling which could lead to switch on or accelerate the function of several genes such as protein kinases and other genes related with photosynthesis and eventially, affect the plant growth. Inoculation with mycorrhiza increased all plant growth variables such as number of leaves, stem fresh and dry weights and root dry weight Shockley et al. (2004). Gahoonia and Nielsen (2004) reported that the inoculation with mycorrhiza enhanced the release of organic acids and higher acid phosphatase activity in the rhizosphere which may be useful for increasing phosphorus acquisition from inorganic and organic phosphorus pools to the plant. Al-Karaki et al. (2004) found that biomass and grain yields were higher in mycorrhizal than non-mycorrhizal plants. Wu et al. (2005) reported biofertilizer as an alternative to chemical one to increase soil fertility and crop production. Glassop et al. (2005) reported that a very large number of plant species are capable of forming symbiotic associations with arbuscular mycorrhizal (AM) fungi. Moreover, they reported that a large number of phosphate (P) transporters have been identified in plants; tissue expression patterns and kinetic information supports the roles of some of these in the direct root uptake pathways. Chen et al. (2007) indicated that the beneficial impacts of mycorrhizal colonization on plant growth could be largely explained by improved P nutrition. On the other hand, Baltruschat et al. (2008) found that the root endophytic basidiomycete Piriformospora indica increase the tolerance against abiotic stress as in many plants. Gryndler et al. (2009) concluded that mycelia of AM fungi are influenced by organic matter decomposition via release of the compounds during the decomposition process and also by secondary metabolites produced by microorganisms involved in organic matter decomposition. Araim et al. (2009) reported that AM colonization significantly increased the mass of shoots and roots and the concentrations of proteins and most of the phenolics in the roots. Hence, the selected trait of mycorrhiza could play an important role in optimizing the growth of E. purpurea by inducing the production of secondary phytomedicinal metabolites. The impact of mycorrhizaon gene expression has been addressed by some recent studies, Hause et al. (2002) reported that colonization of barley (Hordeum vulgare Cv. Salome) roots by an arbuscular mycorrhizal fungus, led to elevated levels of endogenous jasmonic acid (JA) and its amino acid conjugate JA-isoleucine, whereas the level of the JA precursor remained constant. The rise in jasmonate was accompanied by the expression of genes coding for an enzyme of JA biosynthesis. Delp et al. (2003) performed relative quantitative RT-PCR and western blotting to investigate the expression of three genes with potentially regulatory functions from the arbuscular mycorrhizal fungus Glomus intraradices in symbiosis with barley. Weidmann et al. (2004) identified 29 plant genes which were upregulated in response to Medicago truncatula root inoculation with mycorrhiza. Twenty-two protein spots, 14 upregulated and 8 downregulated were found changed in mycorrhiza inoculated plants as compared with the non inoculated ones by Liang et al. (2007). Abo Doma et al. (2008) indicated that the treatment with mycorrhiza significantly increased plant growth in two cultivars of wheat using different yield related traits. Moreover, transcriptome analysis using real timereverse transcriptase indicated that mycorrhiza treatment resulted in an increase in the gene expression of proline 5 carboxilate synthetase (P5CS) on the transcription level. Roldan et al. (2008) indicated that differential gene expression for genes conferring superoxide dismutase and peroxidases were recorded between mycorrhizal and non-mycorrhizal shoots of juniperus oxycedrus seedling. This investigation aimed to: 1- study the effect of barley root inoculation with mycorrhiza on some plant traits and 2-determine the changes in gene expression of the genes conferring calcium dependent protein kinases (CDPKs), phosphoenol pyrovate carboxylases (PEPCs) and proline-5 carboxylate synthetase (P-5CS) in barley plants in response to their inoculation with mycorrhiza at the molecular level as quantified using RT-PCR.

Vesicular-arbuscular mycorrhiza and Trichoderma virdi as deterrents against soil-borne root rot disease of sugar beet

The aim of the present work was to study the effects of vesicular-arbuscular mycorrhiza (VAM) and Trichoderma virdi (T. virdi) fungi as deterrents against Rhizoctonia solani (R. solani) and Fusarium solani (F. solani) infections on the growth and quality of sugar beet. Two experiments were carried out in the greenhouse at the Agriculture Research Center, Giza, Egypt, under greenhouse conditions. The results showed that mycorrhizal and T. virdi inoculation significantly restricted the spread of both soil-borne pathogens in the host root tissues. Disease incidence of sugar beet roots was reduced to 6.2 and 5.2% for mycorrhiza with Rhizoctonia and 5 and 4.5% with Fusarium in the 1st and 2nd seasons respectively. Trichoderma with Rhizoctonia inoculation reduced disease incidence to 6.0 and 5.8% and with Fusarium to 5 and 4.3% in the 1st and 2nd seasons, respectively, compared to pathogen (Rhizoctonia and/or Fusarium) alone. In the first and second seasons, respectively, incidence of R. solani infection, in combination with mycorrhiza treatment, was reduced to 6.2 and 5.2%, and to 5 and 4.5% when amended with F. solani. Dual inoculation with mycorrhizal or T. virdi and the pathogen resulted in increasing total fresh and dry weight, nitrogen (N), phosphorus (K) and potassium (P) contents of sugar beet leaves and roots compared to pathogen-inoculated plants. Furthermore, the same treatments increased yield and quality traits of sugar beet (sucrose, total soluble solids and purity percentage). The use of this microbial model system in biological suppression of R. solani and F. solani will sustain the productivity of sugarbeet.

Optimization of field cultivation of Baptisia tinctoria (L.) R. Br. by fertilizer, mulch and mycorrhiza treatments

Optimization of field cultivation of Baptisia tinctoria (L.) R. Br. by fertilizer, mulch and mycorrhiza treatments

Effect of Verticillium wilt ( Verticillium dahliae Kleb.) and mycorrhiza ( Glomus mosseae) on root colonization, growth and nutrient uptake in tomato and eggplant seedlings

The effect of the arbuscular mycorrhizal fungus (AMF) Glomus mosseae and the soil-borne Verticillium dahliae and their interaction on root colonization, plant growth and nutrient uptake were studied in eggplant and tomato seedlings grown in pots. It was found that: (a) root colonization by the AMF as well as spore formation was higher (34.6 and 30.5%, respectively) in the eggplant than in tomato. Also it was twice as high in the mycorrhiza treatment than in the treatment with the double inoculation (mycorrhiza+ Verticillium); (b) the mycorrhiza treatment increased fresh and dry weight and mean plant height in tomato by 96, 114 and 21% compared to controls. The respective values in eggplant were 114, 104 and 30%; (c) infection by Verticillium reduced fresh weight by 28%, dry weight by 35% and plant height by 14% in tomato. The respective reductions in eggplant were 27, 37 and 12%; (d) the treatment combining both V. dahliae+G. mosseae increased fresh weight by 33%, dry weight by 24% and mean plant height by 21% in tomato. The respective increases in eggplant were 32, 10 and 16%. This leads to the conclusion that the beneficial effect of the AMF supersedes the pathogenic effect of V. dahliae; (e) P and N uptake were higher in mycorrhizal treatments than in controls, although no difference in K, Ca, Mg and B uptake was observed between treatments; (f) mycorrhizal treatments had lower concentrations of micronutrients Zn, Mn, Fe and Cu in shoots and leaves than controls.

Effects of elevated carbon dioxide and arbuscular mycorrhizal infection on Trifolium repens.

Trifolium repens L. cv. aran was grown for 58 d at ambient (350 μol mol(-1) ) and elevated (700 μol mol(-1) ) atmospheric CO2 , wish and without the arbuscular mycorrhizal fungus Glomus mosseae (Nicol. & Gerd.) Gerd. & Trappe cv. YV. Plant biomass, mycorrhizal infection, non-structural carbohydrates, C, N and P content were examined. Elevated CO2 (a) significantly increased above- and below-ground biomass, (b) decreased specific leaf area and specific root length, (c) decreased tissue %N and increased the C:N ratio, and (d) significantly increased total non-structural carbohydrates. Inoculating T. ripens with Glomus mosseae (a) significantly increased above- and below-ground biomass. (b) increased the total root length and total leaf area, and (c) significantly decreased tissue of Evidence of an increased influence of mycorrhiza on the P nutrition of T. repens at elevated CO2 was found in the 22%, increase in leaf total P (P < 005) of mycorrhizal plants grown at elevated CO2 compared with non-mycorrhizal plants. No significant interactions were found between CO2 and mycorrhiza treatments. The proportion of T. repens root length colonized by Glomus mosseae was not affected by CO2 concentration. The percentage mycorrhizal infection was 29% at ambient CO2 and 35%, et al elevated CO2 . However, exposure to elevated CO2 significantly increased the total mycorrhizal foot length from 3.4 to 6.1 m per plant. The results show little evidence that the role of arbuscular mycorrhiza in the growth and nutrition of T. repens would increase if atmospheric CO2 were to increase as predicted.

Manganese reduction in the rhizosphere of mycorrhizal and nonmycorrhizal maize

The influence of rhizosphere microorganisms and vesicular-arbuscular (VA) mycorrhiza on manganese (Mn) uptake in maize (Zea mays L. cv. Tau) plants was studied in pot experiments under controlled environmental conditions. The plants were grown for 7 weeks in sterilized calcareous soil in pots having separate compartments for growth of roots and of VA mycorrhizal fungal hyphae. The soil was left either uninoculated (control) or prior to planting was inoculated with rhizosphere microorganisms only (MO-VA) or with rhizosphere microorganisms together with a VA mycorrhizal fungus [Glomus mosseae (Nicol and Gerd.) Gerdemann and Trappe] (MO+VA). Mycorrhiza treatment did not affect shoot dry weight, but root dry weight was slightly inhibited in the MO+VA and MO-VA treatments compared with the uninoculated control. Concentrations of Mn in shoots decreased in the order MO-VA > MO+VA > control. In the rhizosphere soil, the total microbial population was higher in mycorrhizal (MO+VA) than nonmycorrhizal (MO-VA) treatments, but the proportion of Mn-reducing microbial populations was fivefold higher in the nonmycorrhizal treatment, suggesting substantial qualitative changes in rhizosphere microbial populations upon root infection with the mycorrhizal fungi. The most important microbial group taking part in the reduction of Mn was fluorescent Pseudomonas. Mycorrhizal treatment decreased not only the number of Mn reducers but also the release of Mn-solubilizing root exudates, which were collected by percolation from maize plants cultivated in plastic tubes filled with gravel quartz sand. Compared with mycorrhizal plants, the root exudates of nonmycorrhizal plants had two fold higher capacity for reduction of Mn. Therefore, changes in both rhizosphere microbial population and root exudation are probably responsible for the lower acquisition of Mn in mycorrhizal plants.