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I suspect that by definition the answer is no

Piriformospora indica , a miracle fungus developed by Dr. Ajit Varma, India, which forms arbuscular structure inside roots but not a AM fungi. It is originally isolated from the rhizosphere of woody plants of Prosopis juliflora growing under Thar Desert of Jaisalmer, Rajasthan, India.

The fungus has been named Piriformospora indica based on its characteristic pear-shaped chlamydospores. Molecular phylogenetics have revealed that the fungus is a member of the basidiomycetous order Sebacinales. Plants colonized by P. indica display wide range of beneficial effects (like AM fungi) including enhanced host growth and resistance to biotic and abiotic stresses, promotion of adventitious root formation and enhanced phosphate and nitrate assimilation. The fungus promotes plant growth and health by various mechanisms such as enhanced nutrient uptake, resistance against plant pathogens, and tolerance against salinity, drought, temperature extremes and low nutrient content. Further, it is shown to stimulate excessive production of biomass, early flowering, seed production and a potential microorganisms imparting biological hardening to tissue culture raised plants.

As I think their is no other than AM forms arbuscular structures inside the roots 

In relation to your discussion this is an adaptation of the information from Dr. Varma to make his information more accessible.. This Piriformospora indica mycorrhizae are cultured in common growth media unlike the Arbuscular Mycorrhizae which are obligate plant symbionts not able to be cultured on common growth media. Arbuscles are tree like haustoria although Piriformospora gives intracellular hyphae they are not completely similar to arbuscles. While AM fungi are types of Zygomycetes the Piriformospora are Basidiomycetes. In addition there are mycorrhizae which form fungal sheaths around the roots called ectomycorrhizal which are Basidiomycetes or Ascomycetes. About 80% of all plants have AM fungal types and the other relatioships are not as common.

Piriformospora indica adapted from Dr. Varma

Piriformospora indica, a basidiomycete fungus. It is related to the plant pathogenic Rhizoctonia solani. The fungus was first isolated from the roots of mesquite a woody legume shrub Prosopsis juliflora and the jujube buckthorn shrub Zizisphus nummularia. These species were found in the Great Thar Desert  in India and Pakistan. Unlike the other mycorrhizae such as the arbuscular type that are mostly Zygomycetous and do not grew well in culture. Piriformospora indica is easily grown on laboratory media facilitating its study and propagation.

Figure 1. Piriformospora indica fungus growing on common laboratory growth media. Arbuscular mycorrizal fungi do not readily grow or propagate on laboratory media.

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Figure 2. Comparison of a non inoculated (a) compared to P. indica inoculated plants both grown under the identical greenhouse environments. Note the increased vigor, size and plant color in the inoculated plant.

The growth of P. indica infected plants show increased growth and improved root disease defensive reaction leading to increased plant survival and productivity. Mycorhizal fungus receive their sustenance at the expense of its plant host. Plants which are colonized thrive through the interaction based on the action of fungus to extend the effective root system and by biochemical defense reactions which are triggered. The mycorrhizal fungus promotes more ability react to biotic and abiotic stress and utilize soil nutrients.

Figure 3. Piriformospora indica inoculation in tissue cultured plantlets demonstrate the greatly increased size and vigor when inoculated. In addition the Artemisin, a anti malarial plant metabolite is greatly increased in response to the mycorrhizal inoculation.

Besides its relative ease of laboratory isolation and culture, P. indica has a wide host range which includes many economic plants such as maize Zea mays L., rice Oryza sativa, barley Hordeum vulgare, soybean Glycines max L. Merr. , tomato Lycopersicon esculentum and cabbage Brassica napus to name just a few. Plant mycorrhizal association with it have been found for liverwort Bryophytes, ferns Pterophytes evergreen conifer (Gymnosperns) and seed plant Angiosperms. This type of mycorrhizal fungi are mainly seen in orchids prior to the current discoveries.

Histology The fungus grows mostly into root cortex being inter between and within intracellular in its colonization. The mycorrhizal symbiont fungus does not infect the root core of endodermis and does not penetrate nor colonize any of the aerial tissues or organs of the plant. The fungus also grows and explores the soil outside of its host.

Figure 4. Note the thick walled global chlamydospores in root epidermis cells aligned in a linear fashion. The chlamydospores are a resistant structure promoting survival in difficult environmental conditions until infection courts become available.

The P indica fungus was first detected in the Thar Desert of the Indian subcontinent. When the plants are colonized they have found an array of beneficial reactions such as better resistance and tolerance to stress environments and stimulated growth and nutrient uptake. Of particular interest is the confirmed ability of the fungus to combine with host plants such as barley to tolerate salinity with is severely limiting to crop production in many arid and semi arid environments.

Of the conditions alleviated under P. indica colonization is soybean cyst nematodes Heterodera glycines, sudden death syndrome of Fusarium solani root disease in soybean G. max and eggplant, and in pearl millet Pennisetum glaucum the colonization of P. indica brought improved zinc nutrition.

Figure 5. The obstacles of both salinity and disease can be confronted by P. indica inoculation in barley from these tests under controlled conditions.

Figure 6. The invasion of root tissues by P. indica results in a biochemical cascade of defensive compounds which account for the increase defensive ability of plants in partnership with this fungus. Similar Rhizoctonia solani fungi cause a necrotic cascade with overall negative reaction to the plant. It is possible that mycorrhiza of this type evolved their necrotic parasitism into a balanced relationship for mutual benefits occurred.

Figure 7. The mycorrhizal P. indica can show increased unchanged or decreased growth in response to rhizobacteria which commonly inhabit the root soil interface.

Dear Suvigya Sharma,

Thankz, Dr. J. C. Tarafdar & Dr. Paul Reed Hepperly for the nice information about the miracle of Dr. Varma. Yes, the fungus bears the information to form arbuscle inside plant root. 

Thanks Dr. Milham for the answer I was looking for ... term arbuscule can only be used for AM fungi and off course many thanks to Dr. Salih, Dr. Hepperly and Dr. Tarafdar for your inputs as well !!!