Soil samples from each treatment were analyzed for various physical and chemical properties, like soil texture [13] , pH [14] , total N [15] and AB-DTPA extractable P, Zn, Cu, Fe [16] . Plant N, P, Zn, Cu, Fe and Mn uptakes were calculated by the method described by Jarrel, [17] as shown in Table 1.

Data regarded grain, shoot, root dry matter yields, 100 grain weight, plant nutrient concentration, and their accumulation by plants were analyzed statistically according to the procedure given by Steel and Torrie [18] using the MSTATC package. Arbuscular mycorrhiza fungal spores were isolated from the soil by the techniques as described by Gerdeman and Nicolson, [19] . The isolated spores from the soil sample were identified as per the guideline described by Schneck and Parez [20] . Mycorrhizal infection rates in the roots of wheat were determined according to the procedure as described by Philips and Hyman [21] .

Grains, shoot, root dry matter yield and hundred grains weight of wheat crop as affected by AMF inoculation with heavy metals are presented in Table 2. Data showed that maximum grains and dry matter yield of 4657 and 15915 kg·ha⁻¹ were recorded respectively, in treatment where Zn, Cu, Fe, Mn were applied at double rate of recommended level. Maximum increases in wheat grain and dry matter yield as 36% and 11%, respectively were observed in treatment of Zn, Cu, Fe, Mn applied at double of recommended level over control. When compared with non-inoculated crop, a decreasing trend in grain and dry matter yields of wheat was observed by AMF inoculation with Zn, Cu, Fe, Mn at different level. Maximum root yield of 2.49 kg·ha⁻¹ was noted in treatment of Zn, Cu, Fe, Mn applied at triple of recommended level and mycorrhiza inoculation. Maximum increase in wheat root dry matter yield as 58% was observed in treatment of Zn, Cu, Fe, Mn at triple of recommended level and mycorrhiza over control. When compared with uninoculated crop increasing trend in root dry matter yield of wheat was observed with AMF inoculation with Zn, Cu, Fe and Mn at different levels. Highest 100 grains weight of wheat as 4.85 g was noted in treatment of Zn, Cu, Fe, Mn applied at triple of recommended level with mycorrhiza. The maximum increase in 100 grains weight as 39% was noted in treatment of Zn, Cu, Fe, Mn applied at triple of recommended level with mycorrhiza over control. When compared with uninoculated crop increasing trend in 100 grain weight of wheat was observed by AMF inoculation with Zn, Cu, Fe and Mn at different levels. Sharif and Classen [22] reported that at low P supply, infection with AMF fungi significantly increased the yield of Capsicum annum L. AL-Karaki and Clark [23] . Kahiluoto et al. [24] reported higher mycorrhizal colonization and greater benefit of mycorrhizal association in flax grown on soils with low rather than intermediate initial soil fertility. Rabie [25] found that mycorrhizal inoculation significantly increased root dry weight, total lipid and chlorophyll content in wheat plant. AM fungi can contributed to plant growth, particularly

^*Means with different letter (s) in columns are significantly different at P ≤ 0.05. Recommended levels of Zn, Cu, Fe & Mn were applied @ 2.5, 1.0, 2.5 and 1.0 mg·kg⁻¹ soil, respectively.

in disturb or heavy metal contaminated sites, by increasing plant access to relatively immobile mineral such as P [26] , improving soil texture by binding soil particles into stable aggregates that resist wind and water erosion [27] .

Data regarding post harvest soil N, P, Zn, Cu, Fe and Mn contents as influenced by AMF inoculation and heavy metals are presented in Table 3. Data indicated that total N and AB-DTPA extractable P contents of 1730, 4.78 mg·kg⁻¹, respectively were recorded in the treatment of N, P and K application. The AMF inoculation of wheat reduced post harvest soil Zn, Cu, Fe and Mn contents as compared to uninoculated crop. Maximum content of post harvest soil Zn, Cu. Fe and Mn as 2, 4.4, 2.8 and 2.9 mg·kg⁻¹ was noted in treatment of Zn, Cu, Fe, Mn applied at triple of recommended levels. Mycorrhizal symbiosis increased N content in soil [28] and mycorrhizal symbiosis increased P content in soil [29] . AM broad bean plants had higher shoot and root P, N and K contents than non AM plants, regardless of wastewater treatments [30] . However, both mycorrhizal and non-mycorrhizal

^*Means with different letter (s) in columns are significantly different at P ≤ 0.05. Recommended levels of Zn, Cu, Fe & Mn were applied @ 2.5, 1.0, 2.5 and 1.0 mg·kg⁻¹ soil, respectively.

plants grown in control (unpolluted) soil had higher P, N and K contents than sewage water stressed plants, particularly at higher concentrations (40% and 60%). Arbuscular mycorrhizal fungus enhances soil zinc and copper content [31] [32] . In some circumstances, mycorrhiza fungi protect the plant with heavy metals content [33] . Voegelin et al. [34] observed that some of heavy metals are essential to plant and are required for plant growth and development such as Cu, Zn, Fe, Mo, Ni but their higher soil contents are considered a matter of concerned to society as they adversely affect the quality of soil.

Data regarding Plant N and P uptakes as influenced by AMF inoculation and heavy metals are presented in Table 4. Data on plant N uptake indicated that maximum plant N uptake of 152.4 kg·ha⁻¹ was observed in treatment in which N, P and K were applied. It is evident from the data that plant N uptake decreased by the inoculation of AMF with Zn, Cu, Fe, Mn as compared with uninoculated crops at different levels. Data showed that the highest plant P uptake of 3.25 kg·ha⁻¹ was recorded in treatment in which N, P and K were applied. Plant P uptake decreased by AMF inoculation with Zn, Cu, Fe, Mn as compared with uninoculated crop. Data revealed that AMF inoculation with heavy metal reduced the plant uptake of Zn, Cu, Fe, and Mn as compared to uninoculated treatment. Maximum plant Zn, Cu, Fe, and Mn uptake of 160.6, 206.0, 1941.6 and 2653.0 g·kg⁻¹ was observed in treatment of Zn, Cu, Fe, Mn applied at triple of recommended levels. Plant Zn, Cu, Fe and Mn uptake decreased by the inoculation of AMF when compared with uninoculated crops with Zn, Cu, Fe and Mn applied at different levels. These results are supported by Smith and Read [3] who studied that arbuscular mycorrhiza are one of the most prominent soil microorganisms, which expand the interface between plant and the soil environment and contribute to plant uptake of P and N [7] as well as micronutrient Cu and Zn. Growing broad bean plants with AM inoculum can minimize the heavy metals toxicity and increase the growth and P uptake [30] . AM fungi supply essential nutrients to plant from the soil through uptake by extra radical hyphae [33] , but the fungus may contribute a biological barrier against transfer of heavy metals to shoots [35] . In some cases AM fungi reduce excess plant uptake of trace element like Zn, Cd and Mn [36] whereas in other cases they enhance or have no effect on the uptake [37] . Tonin et al. [38] studied that the ability of AMF fungi isolated from V. calaminaria L. colonized and reduced metal uptake by Trifolium subterraneum L. Use of these fungi resulted in lower accumulation than the use of a metal tolerant AM fungus isolated from a non tolerant plant. The effects of AMF on host plants tolerance to heavy metals may depends on reduced metal uptake because of retention and immobilization in chitin or glomalin in the fungal wall [39] .

Data in Table 5 showed significant (P ≤ 0.05) increase of AMF soil spores density of 24 spores per 20 g soil and wheat root infection rates of 52.3% in treatment of AMF inoculation. There was positive correlation between soil spores density and root infection intensity of AMF (Figure 1). Bafeel [40] demonstrated that the percentages of AM infection in the root of wheat crop significantly reduced at high levels of heavy metals in the soil. AM fungi still function at low levels of heavy metals polluted soil. These results indicated that low concentrations of heavy metals in soil are not harmful to AM fungus. Vogel-Mikus et al. [5] proved the sensitivity of AM symbionts to heavy metal contaminated soil expressed as a reduction in spores germination or root colonization. Heavy metals have been reported to reduce or eliminate AM infection at their higher concentration in the soil, thus interfering with possible beneficial effects of mycorrhizal association. Zandavalli et al. [41] studied Araucaria angustifolia inoculated with Glomus clarum, found that the biomass and N content of A. angustifolia

^*Means with different letter (s) in columns are significantly different at P ≤ 0.05. Recommended levels of Zn, Cu, Fe & Mn were applied @ 2.5, 1.0, 2.5 and 1.0 mg·kg⁻¹ soil, respectively.

^*Means with different letter (s) in columns are significantly different at P ≤ 0.05. Recommended levels of Zn, Cu, Fe & Mn were applied @ 2.5, 1.0, 2.5 and 1.0 mg·kg⁻¹ soil, respectively.

forming AM increased significantly. Arbuscular mycorrhizal fungi may serve as a filtration barrier against transfer of heavy metals to plant through chelation of metals inside the fungus and secretion of various organic compounds by the fungus. These fungi establish mutual symbiosis higher plants, providing a direct physical link between soil and plant roots [2] . Some reports indicated higher concentrations of heavy metals in plant due to AM [35] whereas, other found a reduce plant concentration; i.e. Zn and Cu in mycorrhizal plant [42] . AM fungi are important as they play a vital role in metal tolerance and accumulation [43] .