Neighbor Presence of Plant Growth-promoting Rhizobacteria (PGPR) and Arbuscular Mycorrhizal Fungi (AMF) Can Increase Sorghum Phytoremediation Efficiency in a Soil Treated with Pb Polluted Cow Manure

Abstract

accumulate in living organisms and plants [1]. These elements enter the environment mainly through anthropogenic sources, such as smelting processes, mining, fuel production, and industrial effluents [2]. Therefore, use of proper approached to the reduction of heavy metal availability is essential. Conventional remediation approaches for contaminated soils, sediments, and groundwater are based on the technologies that have been developed over the past two decades [3], including a wide variety of physical, chemical, and thermal treatment alternatives and their combinations, as well as engineering Background: The present study aimed to evaluate the effects of PGPR and AMF on the changes in sorghum phytoremediation efficiency in the soil amended with lead (Pb)polluted cow manure. Methods: Treatments consisted of applying two rates of Pb [0 (Pb0) and 800 (Pb800) mg/kg] polluted cow manure [0 (C0) and 30 (C30) t/ha], two levels of AMF [without (AMF-) and with (AMF+)] and PGPR (without (PGPR-) and with (PGPR+) inoculation. Pseudomonas sp. R9 was considered as a PGPR bacteria. The plant used in this experiment was sorghum. Plant Pb concentration was measured using atomic absorption spectroscopy. Results: The highest plant Pb concentration belonged to the cultivated plant in the soil treated with 30 t/ha Pb-polluted cow manure, while the lowest that was observed in the soil without amending cow manure in the absence of PGPR or AMF. The presence of AMF significantly increased the Pb translocation value and sorghum phytoremediation efficiency by 8% and 13.4%, respectively. Conclusion: According to the results, the inoculated plant with PGPR and AMF had positive effects on increasing Pb phytoremediation efficiency that, which is notable in environmental studies. However, the effects of soil chemical properties on Pb phytoremediation efficiency cannot be overlooked. * This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License which allows users to read, copy, distribute and make derivative works for non-commercial purposes from the material, as long as the author of the original work is cited properly.

Arbuscular Mycorrhizal Fungi Are an Influential Factor in Improving the Phytoremediation of Arsenic, Cadmium, Lead, and Chromium

“…The abundance of Cr in the soil indicates an environmental problem that is most likely originated from human activities, including chemicals used in agriculture, paint and leather industries, alloy production, and stainless steel [182,183]. It can be said that India's tanning industry alone imports between 2000 and In recent years, scientists have noted the positive effect of inoculating plants with AMF and adding earthworms, biochar, cow manure, lignin, and steel slag to increase uptake and stabilize Pb from contaminated environments [5,24,179,180]. They found that combining AMF with other factors improves phytoremediation in Pb-contaminated environments through increasing the uptake of nitrogen, phosphorus, potassium, and iron, reducing Pb transfer from root to shoot, increasing root colonization, improving soil pH, further plant growth, and increasing soil glomalin content [5,24,179,180].…”

Elucidating the Rhizosphere Associated Bacteria for Environmental Sustainability

“…Conventionally, bacterial species in the rhizosphere were isolated and identified using the traditional or culture-based method for isolating and classifying microorganisms. This method's main inadequacy is that it cannot identify the entire microorganism in a sample, making approximately 99% of the microorganism unknown [6]. Thus, only a few bacterial populations has been identified from the rhizosphere soils using conventional techniques, but not until the advent of next-generation sequencing techniques [33].…”

“…In agro-based industry, plant root-associated bacteria have a beneficial effect on the growth and yield of crops and forest trees [5,6]. Plant growth-promoting rhizobacteria Agriculture 2021, 11, 75 2 of 18 (PGPB) are consortia of bacterial species that colonize the plant root region (rhizosphere), impacting plant growth and health advantageously.…”