Therefore, the concept of using VAM fungi as a bio fertilizer, in terms of cost Mycorrhizae are the root-symbionts which obtain their nutrients from the plant and provide American Journal of Plant Nutrition and Fertilization Technology, 5 : the potential of actinorhizal plants and study of symbiotic relationship needs. Those not connected to the fungal network do not get the message to activate The do this through a symbiotic relationship with the plants: nutrients from a larger area of the soil they're planted in, using the many Seeing as how the plant gives the fungi its sugar wouldn't that make the watermelon not. Symbiosis with AM fungi can positively enhance plant nutrient acquisition It has been reported that the use of AM fungi is able to improve fruit yield and WUE .. To gain further insights into the molecular regulation of watermelon seedlings in relation to aboveground components, not only benefits water.
It has been reported that the use of AM fungi is able to improve fruit yield and WUE of watermelon plants under insufficient irrigation conditions Kaya et al.
This suggests an acceptable and promising method to mitigate the adverse effects of water stress on watermelon production in these areas. However, little is known about the mechanisms responsible for improving drought tolerance by inoculating this cucurbit plant species with AM fungi.
The Watermelon [Citrullus lanatus]
Therefore, the AM fungal effects on the drought tolerance of watermelon plants were investigated here and the corresponding mechanisms were explored from both physiological and molecular aspects, focusing particularly on photosynthesis, the antioxidant systems, osmotic adjustment and stress-responsive gene expressions.
The mycorrhizal inoculum was a stock culture of sand, spores with approximately spores per 10 g of air-dried soilhyphae and colonized clover Trifolium repens L.
The treatments consisted of two levels of irrigation and two AMF conditions in a randomized block design, namely: Each treatment included three replications. The growth medium used in the experiments was a 1: The properties of the soil mix were as follows: Each plastic pot was filled with g of air-dried soil mix and 10 g AM inoculum for mycorrhizal plants or the same weight of autoclaved inoculum for non-mycorrhizal plants.
Mycorrhizal inocula were placed directly below the watermelon seeds at the time of sowing. When the plants had 4—5 true leaves, the seedlings were randomly selected and subjected to the water treatments.
All about Mycorrhizae, its benefits, application and research and development
The soil water status was measured daily in the evening, and the amount of water lost was supplied to each pot to maintain the designated soil moisture content. Water loss was evaluated gravimetrically by weighing the pots, and the amount of water loss in each pot was the difference between a re-watered pot and the actual weight of the pot 24 h later.
Aluminum foil was used to cover the pots to minimize water loss Gong et al. After 12 days of treatment, samples were harvested with at least three biological replicates.
Leaf sampling was randomly conducted on the second uppermost fully expanded leaves from the plants in each treatment group. On the last day of the experiment, 12 seedlings were harvested per treatment, carefully washed and divided into shoots and roots.
Chloroplast Ultrastructure Three leaves per treatment were collected to examine the chloroplast ultrastructure of the mesophyll cells. The photosynthesis rate Pn and transpiration rate Tr were recorded automatically. For the histochemical staining of H2O2, leaf disks 1.
- WHAT ARE MYCORRHIZAE?
Superoxide dismutase SOD activity was measured by monitoring the inhibition of the photochemical reduction of NBT as described by Bai et al. CAT activity was assayed by monitoring the decrease in absorbance at nm because of H2O2 decomposition extinction coefficient of The reaction was initiated by adding H2O2.
For APX activity, we determined the decrease in absorbance at nm by tracking the oxidation of reduced ascorbate ASA; extinction coefficient of 2.
The reaction was initiated by adding ASA oxidase. DHAR activity was determined by monitoring the increase in absorbance at nm because of ASA formation extinction coefficient of 14 mM-1 cm The reaction was initiated by adding DHA. Soluble Sugar Content and Proline Determination Total soluble sugar and free proline contents were determined using the anthrone sulphuric acid method and the ninhydrin method, respectively, according to Gao The corresponding specific primers are detailed in Supplementary Table S1.
Percentage values were arcsin transformed before statistical analysis. Mycorrhizae are the root-symbionts which obtain their nutrients from the plant and provide mineral elements like N, P, K, Ca, S and Zn to the host plant. This review is an attempt to explore the suppressing abilities of Arbuscular Mycorrhizal Fungi AMF against soil borne pathogens root feeding nematodes and fungiinfecting various crops. We also determined the capabilities of AMF to increase the productivity of cereal crops, fruits and vegetable crops and highlighted future research directions in mycorrhizal technology.
How to cite this article: A Tool for Sustainable Agriculture. In a mycorrhizal association, the underground mycellium are in contact with plant roots, but without causing any harm to the plant. Fossil evidence Remy et al. Vesicular arbuscular mycorrhizal fungi belong to the class Zygomycetes, order Endogonales Benjamin, and family Endogonaceae. Mycorrhizal fungi are responsible in improving growth of host plant species due to increased nutrient uptake, production of growth promoting substances, tolerance to drought, salinity and synergistic interactions with other beneficial microorganisms Sreenivasa and Bagyaraj, The soil conditions prevalent in sustainable agriculture are likely to be more favorable to AM fungi than are those under conventional agriculture Bethlenfalvay and Schuepp, ; Smith and Read, The natural role of mycorrhizosphere organisms may have been marginalized in intensive agriculture, since microbial communities in conventional farming systems have been modified due to tillage Sturz et al.
Plant Diversity & Symbiotic Relationships
Microbial diversity in these systems has been reduced Maeder et al. Indiscriminate use of inorganic fertilizers contributes enormously in stepping up agricultural production regionally and globally but at the same time its impact on soil fertility, environmental persistence, soil biodiversity, run off concentration and aquaculture pollution cannot be viewed superficially. Increased environmental awareness has progressively led to shift from conventional intensive management to low input crop production.
Conceivably, a wide range of management are available for the management of disease constraints in various crops, but their effective implementation depends on a sound understanding of the physiological response of plants to these stresses.
The present article aims to review the main mechanisms involved in the biological control of diseases induced by soilborne phytopathogens after root colonization with AM fungi. For a better understanding of the possible influence of VA mycorrhizae on host plant, nutrition and on the symbiosis under practical conditions, will be given in more detail. The potential of symbiosis has contributed much to the nitrogen and phosphate economy of natural ecosystems, particularly on infertile sites or in recently denuded areas Wheeler and Miller, In mycorrhizal symbiotic association a third component of bacteria seems to be loosely or tightly associated with the plants and the mycorrhizal fungi and most likely play a key role in mycorrhizal function.
Garbaye acknowledged the term helper bacteria and defined as those bacteria, which support mycorrhizal establishment. The AM fungi have been found to release an unidentified diffusional factor, known as the myc factor, responsible in activating the nodulation factor's inducible gene MtEnod This is the gene which is involved in establishing symbiotic relationship with the nitrogen fixing, rhizobial bacteria Kosuta et al.
Under natural conditions, bacteria associated with mycorrhizal fungi colonize the surface of extraradical hyphae or at least in some fungal taxa, live in the cytoplasm as endobacteria.
The plant provides the fungus with photosynthetically derived carbohydrate, while the fungus supplies the plant roots with nutrients Smith and Read, The AM fungi are important to their hosts as they enhance the ability of plants to absorb phosphorus from soil, which is relatively inaccessible to the plants Mcgonigle and Miller, ; Miller, However, the AM association may also increase the phytoavailability of micronutrients, e.
In a study, absorption of trace elements, such as boron and molybdenum, was thought to be enhanced by VA mycorrhizae Sieverding, In addition, it has been suggested that some AM associations are able to mobilize organically bound nitrogen, which the plants are unable to absorb Hodge et al. Symbiotic association of AM fungi with the plants seems influence the composition of bacterial communities in the mycorrhizosphere due to changes in root exudation patterns induced by AM colonization Marschner and Baumann, ; Soderberg et al.
The manipulation of crop rhizosphere with PGPR for biocontrol of plant pathogens has been found promising Nelson, ; Ren et al. Changes in bacterial community structure may also be driven by complex interactions between plant species or genotype and fungal species involved Marschner and Baumann, ; Marschner and Timonen, The increased host phosphorus provided by fungus supports rhizobial production of nitrogenase enzymes, which are important for nitrogen fixation Puppi et al.
The enhanced nitrogen status of the plant promotes further development of the mycorrhizal symbiosis. The biofertilizer properties of plant growth promoting rhizobacteria are frequently ascribed to their ability to increase the bioavailability of inorganic and organic phosphorus and some of these bacteria have documented synergistic effects on nitrogen fixation and formation of mycorrhizal associations. Phosphorus content in tomato plants was increased when inoculated with the AM fungus G.
Additionally, the highest nitrogen and phosphorus uptake was observed when tomatoes were inoculated with both the organisms, suggesting that bacteria and AM fungi might together increase the rate of nutrient uptake by the plants.