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Many studies have conducted to determine the best management practice to reduce the mobility and phytoavailability of the trace metals in contaminated soils. In this study, geochemical speciation and phytoavailability of Zn for sunflower were studied after application of nanoparticles (SiO and zeolite, with an application rate of 200 mg kg) and bacteria [Bacillus safensis FO-036b(T) and Pseudomonas fluorescens p.f.169] to a calcareous heavily contaminated soil. Results showed that the biotic and abiotic treatments significantly reduced the Zn concentration in the aboveground to non-toxicity levels compared to the control treatment, and the nanoparticle treatments were more effective than the bacteria and control treatments. The concentration of CaCl-extractable Zn in the treated soils was significantly lower than those of the control treatment. The results of sequential extraction showed that the maximum portion of total Zn belonged to the fraction associated with iron and manganese oxides. On the contrary, the minimum percent belonged to the exchangeable and water-soluble Zn (F). From the environmental point of view, the fraction associated with iron and manganese oxides is less bioavailable than the F and carbonated fractions. On the basis of plant growth promotion, simultaneous application of the biotic and abiotic treatments significantly increased the aboveground dry biomass yield and also significantly reduced the CaCl-extractable form, uptake by aboveground and translocation factor of Zn compared to the control treatment. Therefore, it might be suggested as an efficient strategy to promote the plant growth and reduce the mobile and available forms of toxic metals in calcareous heavily contaminated soils.

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Fruit crops offer a strong sink for sequestration of atmospheric carbon dioxide, thereby, aid in moderating the impact of climate change-related issues, besides creating a parallel nutrient sink. Mere annual application of organic manures/composts has failed to address different soil fertility functions due to failure to prolong the impact of soil organic pool on long-term basis. The paradigm shifts from purely inorganic to either organic fertilizers or in combination with chemical fertilizers and microbial inoculants (preferably in consortium mode) started gaining wide scale use for enhanced soil health vis-à-vis elevated quality production and reduced rhizosphere CO 2 emmission. This change of concept later formed the basis for Integrated Soil Fertility Management (ISFM)-based strategy involving three basic components viz., microbial inoculants (biofertilizers), inorganic fertilizers, and organic fertilizers. Development of microbial consortium exploiting the microbial synergisms with variety of fruit crops as an important component of ISFM is one of the popular methods of managing multiple soil fertility constraints occurring within the rhizosphere. Further advancements in rhizosphere-specific consortia (often by scaling up crop-microbiome) mediated ISFM could further fulfil the nutrient demand and supply by crop. Upscaling such studies through rhizosphere hybridization has provided some initial inroads in harnessing the potential of different rhizosphere microbial communities. ISFM studies carried out in fruit crops in India, Iran, and China showed better agronomic response and soil health-related properties, considered very close to climate-resilient soil fertility management, a gateway to sustainable quality production. The review also highlights the future directions for ISFM in fruit crops catering to their multiple requirements.

Problem statement: Contents of heavy metals in soil are very important because soil is the first link in the food chain. Approach: But, pay attention to importance the subject, we performed this project to investigate the lead (Pb) and Cadmium (Cd) availability and uptake by rice plant in response to different biosolids Municipal Solid Waste (MSW), Vermicompost (VC) and inorganic Fertilizers (CF) using split plot arrangement based on randomized complete block design with three replications in 2008. Results: The results showed that fertilizer and application periods treatments influenced Pb and Cd accumulation. The highest available Pb (4.89 ppm) and Cd (0.173 ppm) belong to 3 years application of 40 ton.ha^-1 MSW +1/2 CF treatment. During 3 years application of 20 ton.ha^-1 MSW+1/2 CF the most Pb accumulated in root. Conclusion: The maximum Pb uptake by shoot and grain happened in 40 ton.ha^-1 MSW treatment. With application 40 ton.ha^-1 VC +1/2 CF, the maximum Cd accumulated in root. During 3 years application of 40 ton.ha^-1 MSW and 20 ton.ha^-1 VC the highest Cd uptaked by shoot. While, the maximum Cd concentration in grain belong to 20 ton.ha^-1 MSW +1/2CF and CF treatments when added to soil for 3 continuous years

Trace toxic elements often restrict the land application of different bio-solids in agriculture. In order to evaluate the separate influence of the municipal solid waste compost (MSW), sewage sludge (SS) and combined application with inorganic fertilizers (chemical fertilizer (CF)) on nutritional (Fe, Mn, Ni, and Cr) and growth responses of rice plant, a research was conducted on paddy soil from 2013 to 2015. Obtained results showed that SS levels were superior to MSW in most studied traits. The maximum chlorophyll content (46.52), plant height (162.6 cm), biomass (23.33 t ha), soil available Fe (206.26 ppm), Ni concentration in the root (14.41 ppm) and shoots (3.16 ppm), Cr concentration in the root (12.43 ppm) and grain (3.65 ppm), and Mn concentration in grain (66.938 ppm) belonged to SS levels, specially enriched 40 t ha, when it was added to the soil for three continuous years. The highest 1000-grain weight (29.89 g), yield (6.86 t ha), harvest index (48.17%), and soil available Mn (712.7 ppm), Fe, and Ni concentration in grain (107.92 and 8.79 ppm, respectively) were recorded in 3 years of applying the enriched 40 t ha MSW. Accumulation of Ni in grain in critical levels and negative effects of CF treatments on toxic element entry to soil and plant were two important findings of this research that need management.