Genetic analysis of the modern Australian labradoodle dog breed reveals an excess of the poodle genome.

The genomic diversity of the domestic dog is an invaluable resource for advancing understanding of mammalian biology, evolutionary biology, morphologic variation, and behavior. There are approximately 350 recognized breeds in the world today, many established through hybridization and selection followed by intense breeding programs aimed at retaining or enhancing specific traits. As a result, many breeds suffer from an excess of particular diseases, one of many factors leading to the recent trend of "designer breed" development, i.e. crossing purebred dogs from existing breeds in the hope that offspring will be enriched for desired traits and characteristics of the parental breeds. We used a dense panel of 150,106 SNPs to analyze the population structure of the Australian labradoodle (ALBD), to understand how such breeds are developed. Haplotype and admixture analyses show that breeds other than the poodle (POOD) and Labrador retriever (LAB) contributed to ALBD formation, but that the breed is, at the genetic level, predominantly POOD, with all small and large varieties contributing to its construction. Allele frequency analysis reveals that the breed is enhanced for variants associated with a poodle-like coat, which is perceived by breeders to have an association with hypoallergenicity. We observed little enhancement for LAB-specific alleles. This study provides a blueprint for understanding how dog breeds are formed, highlighting the limited scope of desired traits in defining new breeds.

Genetic Origins of the Two Canis lupus familiaris (Dog) Freight Dog Populations.

Despite periodic drops in popularity, Arctic sled dogs continue to play a vital role in northern societies, providing both freight transit and recreational race activities. In this study, we selected the Mackenzie River Husky, a freight dog of complex history, and the Chinook, an American Kennel Club recognized freight dog breed whose heritage reportedly overlaps that of the MKRH, for detailed population analysis. We tested each to determine their component breeds and used admixture analysis to ascertain their population structure. We utilized haplotype analysis to identify genomic regions shared between each population and their founding breeds. Our data show that the Alaskan Malamutes and modern Greenland sled dog contributed to both populations, but there are also unexpected contributions from the German Shepherd dog and Collie. We used haplotype analysis to identify genomic regions nearing fixation in population type and identify provocative genes in each region. Finally, in response to recent reports regarding the importance of dietary lipid genes in Arctic dogs, we analyzed 8 such genes in a targeted analysis observing signatures of selection in both populations at the MLXIPL gene loci. These data highlight the genetic routes that breeds of similar function have taken toward their occupation as successful sled dogs.

An ultra low-cost smartphone device for in-situ monitoring of acute organophosphorus poisoning for agricultural workers.

In this work, we present an ultra-low-cost smartphone device for in situ quantification of OP poisoning severity. The performance of the lens-less smartphone spectrum apparatus (LeSSA) is evaluated using standard human Interleukin-6 (IL-6) immunoassay kits. Upon dose-response curve fitting, LeSSA demonstrates an accuracy of 99.5%. The limit of detection (LOD) of LeSSA was evaluated through comparison of 6.4 pg/ml with standard laboratory grade UV-vis spectrophotometer at 5.5 pg/ml. Evaluating the capacity of LeSSA in spike solution by combining plasma cholinesterase (PChE) and human plasma shows consistency at agreement of 97.6% between LeSSA and the laboratory instrument. For application demonstration, the activity of PChE for 24 agricultural workers' plasma samples was measured with LeSSA, showing exceptional agreement (r2 = 0.92) with the laboratory instrument reference. In addition to near laboratory grade accuracy, the total manufacturing cost of LeSSA is only $20 USD highlighting it's affordability. With LeSSA, clinicians can evaluate OP poisoning severity without the need to transport patient samples to facilities at far distances. Utilizing LeSSA, immediate results can be used for administration of appropriate treatment.

Determination of insecticide residues and their adverse effects on blood profile of occupationally exposed individuals.

Insecticides, essential for crop protection measures, leave behind several toxic residues that can result in a series of human health disorders. Therefore, this study was planned for the determination of residues and adverse effects of insecticides in blood samples of sprayers, pesticide-industry workers and controls by using blood parameters of these individuals as biomarkers. Optimized analytical methods using GC-MS and HPLC for the simultaneous detection of 22 currently used insecticides were adopted. Eight of twenty-seven (22.22%) sprayers' blood samples were found positive for five different insecticides. Eleven of twenty-seven (40.74%) pesticide-industry workers were found positive for eight different insecticides. The blood samples of both the exposed groups, sprayers and industry workers had significantly (P < 0.001; Mann-Whitney U-tests) low hemoglobin-Hb concentrations (12.17 ±â€¯2.13 and 12.22 ±â€¯2.37 g/dl respectively) than the average value of the control group with 14.23 ±â€¯2.37 g/dl. The erythrocyte sedimentation rates (ESRs) in sprayers and insecticide industry workers (28.78 ±â€¯20.72 and 28.17 ±â€¯25.14 mm/1st h respectively) were greater significantly (P < 0.001; Mann-Whitney U test) than the control blood samples (9.53 ±â€¯3.34 mm/1st h). These results indicate that the exposed individuals have experienced significant hemotoxic effects during insecticide exposure. The study also predicts the risk to exposed individuals in developing countries like Pakistan and demands realization of safety measures to prevent such dangerous effects of pesticide exposures.

Pesticide genotoxicity in cotton picking women in Pakistan evaluated using comet assay.

To control agricultural pests and meet the increasing food demands, pesticides use has been increased substantially over time. Although pesticides are relatively specific to their targets, they can affect non-target organisms and are hazardous for the population around the application areas particularly to the individuals engaged in different types of agricultural activities. This situation is worse in developing and under-developed countries where personal protective equipment is merely used and regulatory guidelines are hardly practiced. In the present study, DNA damage in women exposed to pesticides while picking cotton with bare hands was assessed using single cell gel electrophoresis assay or comet assay. The presence of pesticides in blood serum of exposed individuals was also analyzed using high-performance liquid chromatography. Blood samples were collected from 138 (69 exposed and 69 control) randomly selected females from a major cotton growing area (Bahawalpur District) of the Punjab province of Pakistan. DNA damage, as determined by the mean comet tail length, was significantly higher (p < 0.001) in the exposed group compared to the unexposed. A positive correlation of DNA damage with age and exposure time was also observed. Residues of three pesticides, cyhalothrin, endosulfan, and deltamethrin found significantly higher (p < 0.001) in the serum samples of the exposed group compared to the unexposed. It was observed that the groups with higher mean comet tail length also had a higher concentration of pesticides in their serum samples indicating a positive association of DNA damage and pesticide exposure. The present study suggests that exposure to pesticides leads to DNA damage.

Successful phytoremediation of crude-oil contaminated soil at an oil exploration and production company by plants-bacterial synergism.

Phytoremediation is a promising approach for the cleanup of soil contaminated with petroleum hydrocarbons. This study aimed to develop plant-bacterial synergism for the successful remediation of crude oil-contaminated soil. A consortia of three endophytic bacteria was augmented to two grasses, Leptochloa fusca and Brachiaria mutica, grown in oil-contaminated soil (46.8 g oil kg-1 soil) in the vicinity of an oil exploration and production company. Endophytes augmentation improved plant growth, crude oil degradation, and soil health. Maximum oil degradation (80%) was achieved with B. mutica plants augmented with the endophytes and it was significantly (P < 0.05) higher than the use of plants or bacteria individually. Moreover, endophytes showed more persistence, the abundance and expression of alkB gene in the rhizosphere as well as in the endosphere of the tested plants than in unvegetated soil. A positive relationship (r = 0.70) observed between gene expression and crude oil reduction indicates that catabolic gene expression is important for hydrocarbon mineralization. This investigation showed that the use of endophytes with appropriate plant is an effective strategy for the cleanup of oil-contaminated soil under field conditions.

Bacterial rhizosphere and endosphere populations associated with grasses and trees to be used for phytoremediation of crude oil contaminated soil.

Different grasses and trees were tested for their growth in a crude oil contaminated soil. Three grasses, Lolium perenne, Leptochloa fusca, Brachiaria mutica, and two trees, Lecucaena leucocephala and Acacia ampliceps, were selected to investigate the diversity of hydrocarbon-degrading rhizospheric and endophytic bacteria. We found a higher number of hydrocarbon degrading bacteria associated with grasses than trees and that the endophytic bacteria were taxonomically different from rhizosphere associated bacteria showing their spatial distribution with reference to plant compartment as well as genotype. The rhizospheric soil yielded 22 (59.45 %), root interior yielded 9 (24.32 %) and shoot interior yielded 6 (16.21 %) hydrocarbon-degrading bacteria. These bacteria possessed genes encoding alkane hydroxylase and showed multiple plant growth-promoting activities. Bacillus (48.64 %) and Acinetobacter (18.91 %) were dominant genera found in this study. At 2 % crude oil concentration, all bacterial isolates exhibited 25 %-78 % oil degradation and Acinetobacter sp. strain BRSI56 degraded maximum. Our study suggests that for practical application, support of potential bacteria combined with the grasses is more effective approach than trees to remediate oil contaminated soils.

Mutant frequency in comparison to oxidative DNA damage induced by ochratoxin A in L5178Y tk+/- (3.7.2C) mouse lymphoma cells.

Ochratoxin A (OTA) is a naturally occurring mycotoxin that contaminates animal feed and human food. OTA is nephrotoxic, hepatotoxic, immunosuppressive and a potent renal carcinogen in rodents. In the present study, we evaluated the genotoxicity of OTA in L5178Y tk(+/-) (3.7.2C) mouse lymphoma cells using the microwell version of the mouse lymphoma gene mutation assay (MLA) and the comet assay modified to detect oxidative DNA damage. Cells were treated for 4 hours with 0, 5, 10, 25, 50 or 100 µM of OTA in the presence and absence of exogenous metabolic activation (S9). Benzo[a]pyrene (1 µg/mL) and 4-nitroquinoline-1-oxide (0.1 µg/mL) were used as positive control with and without S9, respectively. OTA treatment produced dose-dependent increases in cytotoxicity and tk mutant frequency, with significant increases in mutant frequency detected at concentrations ≥25 µM with and without S9. Similarly treated cells were used for the comet assay conducted with and without formamidopyrimidine-DNA glycosylase for the determination of oxidative DNA damage. OTA exposure resulted in a significant increase in both direct and oxidative DNA damage, with induction of oxidative damage being greater. The results indicate that OTA is mutagenic in mouse lymphoma assay; and that OTA-generated oxidative DNA damage is, at least partially, responsible for its mutagenicity in the assay.

Genotoxicity of TiO(2) anatase nanoparticles in B6C3F1 male mice evaluated using Pig-a and flow cytometric micronucleus assays.

In vivo micronucleus and Pig-a (phosphatidylinositol glycan, class A gene) mutation assays were conducted to evaluate the genotoxicity of 10 nm titanium dioxide anatase nanoparticles (TiO(2)-NPs) in mice. Groups of five 6-7-week-old male B6C3F1 mice were treated intravenously for three consecutive days with 0.5, 5.0, and 50 mg/kg TiO(2)-NPs for the two assays; mouse blood was sampled one day before the treatment and on Day 4, and Weeks 1, 2, 4, and 6 after the beginning of the treatment; Pig-a mutant frequencies were determined at Day -1 and Weeks 1, 2, 4 and 6, while percent micronucleated-reticulocyte (%MN-RET) frequencies were measured on Day 4 only. Additional animals were treated intravenously with three daily doses of 50 mg.kg TiO(2)-NPs for the measurement of titanium levels in bone marrow after 4, 24, and 48 h of the last treatment. The measurement indicated that the accumulation of the nanoparticles reached the peak in the tissue 4 h after the administration and the levels were maintained for a few days. No increase in either Pig-a mutant frequency of the frequency of %MN-RETs was detected, although the %RETs was reduced in the treated animals on Day 4 in a dose-dependent manner indicating cytotoxicity of TiO(2)-NPs in the bone marrow. These results suggest that although TiO(2)-NPs can reach the mouse bone marrow and are capable of inducing cytotoxicity, the nanoparticles are not genotoxic when assessed with in vivo micronucleus and Pig-a gene mutation tests.

Toxicity assessment of emamectin benzoate and its commercially available formulations in Pakistan by in vivo and in vitro assays.

Emamectin benzoate (EMB) is generally considered a safe insecticide in agriculture and veterinary practices, yet, it can cause cytotoxic and genotoxic effects. Hence, the aim of this study was to evaluate toxic effects of 80% EMB and its commercially used formulations (Tycon 1.9% EC and Tycon plus 5% EW) in Pakistan and tested for acute toxicity in albino rats, rabbits and fish (Labeo rohita). Genotoxicity was investigated by in vivo comet assay and bone marrow micronucleues test in the rats. In vitro mutagenicity was tested in Salmonella typhimurium TA98 and TA100. The tested EMB formulations were found moderately toxic (oral LD50: 122-168 mg/kg), causing severe eye irritation in rabbits, highly toxic to fish (LC50: 9-43 µg/L) and found non mutagenic. Oral administrations of EMB (80% and 5%) at 100 mg/kg of body weight to male rats reduced red blood cells, hemoglobin, and slightly increased the blood glucose, urea and liver enzymes levels but had no significant damage to DNA. EMB induced bone marrow toxicity was observed as reduction of polychromatic erythrocytes. Overall, EMB exposure was highly toxic to fish, and caused hemo- and hepatotoxicity in rats. These findings warrant cautious use of EMB formulations in agrochemicals and veterinary medicine.

Comparative analysis of micronuclei and DNA damage induced by Ochratoxin A in two mammalian cell lines.

The fungal toxin, Ochratoxin A (OTA), is a common contaminant in human food and animal feed. The present study evaluated micronucleus (MN) induction by OTA in comparison with its ability to induce cytotoxicity and DNA damage in two mammalian cell lines, CHO-K1-BH(4) Chinese hamster ovary cells and TK6 human lymphoblastoid cells. Micronuclei were evaluated by flow cytometry, cytotoxicity was estimated by relative population doubling (RPD), while direct DNA damage and oxidative DNA damage were measured with the Comet assay, performed without and with digestion by formamidopyrimidine-DNA glycosylase (fpg). For the MN and cytotoxicity measurements, the cell lines were treated for 24h (CHO cells) or 27h (TK6 cells) with 5-25µM OTA in the absence of exogenous metabolic activation. The OTA treatments resulted in concentration-responsive increases in cytotoxicity, with higher concentrations of the agent being more cytotoxic in CHO cells than TK6 cells. 15µM OTA produced positive responses for MN induction and hypodiploid events (a measure of aneugenicity) in both cell lines; this concentration of OTA also produced cytotoxicity near to the recommended limit for the assay (45±5% RPD). A time course assay with TK6 cells indicated that at least 4h of OTA treatment were required to produce a positive MN response. For the Comet assay DNA damage assessments, the cell lines were treated with 5-50µM OTA for 4h. Direct DNA damage was detected in TK6 cells, but not CHO cells, while concentration-related increases in fpg-sensitive sites were detected for both cell lines. The consistent association of oxidative DNA damage with OTA exposure suggests its involvement in producing OTA-induced clastogenicity and aneugenicity; however, based on its detection in TK6 cells direct DNA damage could be involved in any human risk posed by OTA exposure.

Antioxidant and antimicrobial attributes and phenolics of different solvent extracts from leaves, flowers and bark of Gold Mohar [Delonix regia (Bojer ex Hook.) Raf].

This paper describes the antioxidant and antimicrobial activities and phenolic components of different solvent (absolute methanol, absolute ethanol, absolute acetone, 80% methanol, 80% ethanol, 80% acetone and deionized water) extracts of leaves, flowers and bark of Gold Mohar [Delonix regia (Bojer ex Hook.) Raf.]. The extract yields from leaves, flowers and bark ranged from 10.19 to 36.24, 12.97 to 48.47 and 4.22 to 8.48 g/100 g dry weight (DW), respectively. Overall, 80% methanol extract produced from the leaves exhibited significantly (P < 0.05) higher antioxidant activity, with high phenolic contents (3.63 g GAE/100 g DW), total flavonoid contents (1.19 g CE/100 g DW), inhibition of peroxidation (85.54%), DPPH scavenging capacity (IC(50) value 8.89 µg/mL) and reducing power (1.87). Similarly, this 80% methanol leaves extract also showed superior antimicrobial activity. HPLC analysis of the 80% methanol extracts for individual phenolics revealed the presence of gallic, protocatechuic and salicylic acid in leaves; gallic, protocatechuic, salicylic, trans-cinnamic and chlorogenic acid in flowers, and gallic acid in bark as the main (amount > 1.50 mg/100 g DW) phenolic acids. Besides, small amounts ( < 1.50 mg/100 g DW) of some other phenolic acids such as sorbic, sinapic, p-coumaric, m-coumaric, ferulic, caffeic, 3-hydroxybenzoic, 4-hydroxycinnamic and 4-hydroxybenzoic acids were also detected. The extracts of the tested parts of Gold Mohar, especially, the leaves, might be valuable for functional food and therapeutic applications.

Insecticide toxic effects and blood biochemical alterations in occupationally exposed individuals in Punjab, Pakistan.

Biomonitoring of people exposed to hazardous materials provides opportunities for early identification of several diseases, particularly in those individuals who are constantly exposed to pesticides, such as pesticide operators and workers in pesticide manufacturing industry. However, data on this hot topic are limited in Pakistan. In this study, insecticide toxic effects and biochemical alterations (i.e., damage in DNA and enzyme activity) were studied in blood samples of occupationally exposed individuals from Punjab, Pakistan. Eight out of twenty-seven blood samples (29.6%) of the pesticide operators were found positive in five insecticides, with the maximum concentration found for chlorpyrifos-methyl (0.039 µg/mL). Eleven out of twenty-seven blood samples (40.7%) of the pesticide industry workers were found positive in eight insecticides, with the maximum concentration found for endosulfan (0.051 µg/mL). Comet tail length was 16.88 ±â€¯4.57 µm in pesticide industry workers and 16.33 ±â€¯3.78 µm in pesticide operators, which were significantly higher (P < 0.01) than that recorded in the control group (4.84 ±â€¯2.21 µm). Values of serum cholinesterase (SChE) concentration were slightly lower (P > 0.05) in exposed individuals, whereas values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) concentration were significantly higher (P < 0.01) in exposed individuals compared with control group. Exposure duration and total insecticide concentration in blood samples were positively associated with comet tail length, ALT activity, AST activity, and ALP activity, but negatively with SChE. DNA damage was higher in smokers vs. non-smokers. Also, a positive association was found between comet tail length and number of cigarettes per day. Overall, occupational exposure to insecticides can pose serious health risks to pesticide operators and workers in pesticide manufacturing industry, highlighting the necessity of personal protection in those groups for preventing exposure and resultant health disorders.

RETRACTED:Insecticide exposure affects DNA and antioxidant enzymes activity in honey bee species Apis florea and A. dorsata: Evidence from Punjab, Pakistan.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). After a thorough investigation, the Editors have concluded that the acceptance of this article was partly based upon the positive advice of two illegitimate reviewer reports. The reports were submitted from email accounts which were provided by the corresponding author Christos A. Damalas as suggested reviewers during the submission of the article. Although purportedly real reviewer accounts, the Editors have concluded that these were not of appropriate, independent reviewers. This manipulation of the peer-review process represents a clear violation of the fundamentals of peer review, our publishing policies, and publishing ethics standards. Apologies are offered to the reviewers whose identity was assumed and to the readers of the journal that this deception was not detected during the submission process.

Endophytic bacteria: prospects and applications for the phytoremediation of organic pollutants.

Recently, there has been an increased effort to enhance the efficacy of phytoremediation of contaminated environments by exploiting plant-microbe interactions. The combined use of plants and endophytic bacteria is an emerging approach for the clean-up of soil and water polluted with organic compounds. In plant-endophyte partnerships, plants provide the habitat as well as nutrients to their associated endophytic bacteria. In response, endophytic bacteria with appropriate degradation pathways and metabolic activities enhance degradation of organic pollutants, and diminish phytotoxicity and evapotranspiration of organic pollutants. Moreover, endophytic bacteria possessing plant growth-promoting activities enhance the plant's adaptation and growth in soil and water contaminated with organic pollutants. Overall, the application of endophytic bacteria gives new insights into novel protocols to improve phytoremediation efficiency. However, successful application of plant-endophyte partnerships for the clean-up of an environment contaminated with organic compounds depends on the abundance and activity of the degrading endophyte in different plant compartments. Although many endophytic bacteria have the potential to degrade organic pollutants and improve plant growth, their contribution to enhance phytoremediation efficiency is still underestimated. A better knowledge of plant-endophyte interactions could be utilized to increase the remediation of polluted soil environments and to protect the foodstuff by decreasing agrochemical residues in food crops.

Nutrients can enhance the abundance and expression of alkane hydroxylase CYP153 gene in the rhizosphere of ryegrass planted in hydrocarbon-polluted soil.

Plant-bacteria partnership is a promising strategy for the remediation of soil and water polluted with hydrocarbons. However, the limitation of major nutrients (N, P and K) in soil affects the survival and metabolic activity of plant associated bacteria. The objective of this study was to explore the effects of nutrients on survival and metabolic activity of an alkane degrading rhizo-bacterium. Annual ryegrass (Lolium multiflorum) was grown in diesel-contaminated soil and inoculated with an alkane degrading bacterium, Pantoea sp. strain BTRH79, in greenhouse experiments. Two levels of nutrients were applied and plant growth, hydrocarbon removal, and gene abundance and expression were determined after 100 days of sowing of ryegrass. Results obtained from these experiments showed that the bacterial inoculation improved plant growth and hydrocarbon degradation and these were further enhanced by nutrients application. Maximum plant biomass production and hydrocarbon mineralization was observed by the combined use of inoculum and higher level of nutrients. The presence of nutrients in soil enhanced the colonization and metabolic activity of the inoculated bacterium in the rhizosphere. The abundance and expression of CYP153 gene in the rhizosphere of ryegrass was found to be directly associated with the level of applied nutrients. Enhanced hydrocarbon degradation was associated with the population of the inoculum bacterium, the abundance and expression of CYP153 gene in the rhizosphere of ryegrass. It is thus concluded that the combination between vegetation, inoculation with pollutant-degrading bacteria and nutrients amendment was an efficient approach to reduce hydrocarbon contamination.

Combined use of alkane-degrading and plant growth-promoting bacteria enhanced phytoremediation of diesel contaminated soil.

Inoculation of plants with pollutant-degrading and plant growth-promoting microorganisms is a simple strategy to enhance phytoremediation activity. The objective of this study was to determine the effect of inoculation of different bacterial strains, possessing alkane-degradation and 1-amino-cyclopropane-1 -carboxylic acid (ACC) deaminase activity, on plant growth and phytoremediation activity. Carpet grass (Axonopus affinis) was planted in soil spiked with diesel (1% w/w) for 90 days and inoculated with different bacterial strains, Pseudomonas sp. ITRH25, Pantoea sp. BTRH79 and Burkholderia sp. PsJN, individually and in combination. Generally, bacterial application increased total numbers of culturable hydrocarbon-degrading bacteria in the rhizosphere ofcarpet grass, plant biomass production, hydrocarbon degradation and reduced genotoxicity. Bacterial strains possessing different beneficial traits affect plant growth and phytoremediation activity in different ways. Maximum bacterial population, plant biomass production and hydrocarbon degradation were achieved when carpet grass was inoculated with a consortium of three strains. Enhanced plant biomass production and hydrocarbon degradation were associated with increased numbers of culturable hydrocarbon-degrading bacteria in the rhizosphere of carpet grass. The present study revealed that the combined use of different bacterial strains, exhibiting different beneficial traits, is a highly effective strategy to improve plant growth and phytoremediation activity.

Cr-resistant rhizo- and endophytic bacteria associated with Prosopis juliflora and their potential as phytoremediation enhancing agents in metal-degraded soils.

Prosopis juliflora is characterized by distinct and profuse growth even in nutritionally poor soil and environmentally stressed conditions and is believed to harbor some novel heavy metal-resistant bacteria in the rhizosphere and endosphere. This study was performed to isolate and characterize Cr-resistant bacteria from the rhizosphere and endosphere of P. juliflora growing on the tannery effluent contaminated soil. A total of 5 and 21 bacterial strains were isolated from the rhizosphere and endosphere, respectively, and were shown to tolerate Cr up to 3000 mg l(-1). These isolates also exhibited tolerance to other toxic heavy metals such as, Cd, Cu, Pb, and Zn, and high concentration (174 g l(-1)) of NaCl. Moreover, most of the isolated bacterial strains showed one or more plant growth-promoting activities. The phylogenetic analysis of the 16S rRNA gene showed that the predominant species included Bacillus, Staphylococcus and Aerococcus. As far as we know, this is the first report analyzing rhizo- and endophytic bacterial communities associated with P. juliflora growing on the tannery effluent contaminated soil. The inoculation of three isolates to ryegrass (Lolium multiflorum L.) improved plant growth and heavy metal removal from the tannery effluent contaminated soil suggesting that these bacteria could enhance the establishment of the plant in contaminated soil and also improve the efficiency of phytoremediation of heavy metal-degraded soils.

Plant-bacteria partnerships for the remediation of hydrocarbon contaminated soils.

Plant-bacteria partnerships have been extensively studied and applied to improve crop yield. In addition to their application in agriculture, a promising field to exploit plant-bacteria partnerships is the remediation of soil and water polluted with hydrocarbons. Application of effective plant-bacteria partnerships for the remediation of hydrocarbons depend mainly on the presence and metabolic activities of plant associated rhizo- and endophytic bacteria possessing specific genes required for the degradation of hydrocarbon pollutants. Plants and their associated bacteria interact with each other whereby plant supplies the bacteria with a special carbon source that stimulates the bacteria to degrade organic contaminants in the soil. In return, plant associated-bacteria can support their host plant to overcome contaminated-induced stress responses, and improve plant growth and development. In addition, plants further get benefits from their associated-bacteria possessing hydrocarbon-degradation potential, leading to enhanced hydrocarbon mineralization and lowering of both phytotoxicity and evapotranspiration of volatile hydrocarbons. A better understanding of plant-bacteria partnerships could be exploited to enhance the remediation of hydrocarbon contaminated soils in conjunction with sustainable production of non-food crops for biomass and biofuel production.