Muhammad Farooq Hussain Munis

The potential of the flora from different regions of Pakistan in phytoremediation: a review

Soil and water quality is greatly affected by environmental pollution due to the increasing trend of urbanization and industrialization. In many developing countries, including Pakistan, the situation is more alarming as no preventive measures are still taken to tackle the problem. Although in developed countries, many techniques are used to remediate the environment including phytoremediation. It is the most eco-friendly technique in which plants are used to remove pollutants from the environment. Pakistan has also a great diversity of plants which could be used for the remediation of environmental pollutants. To our knowledge, few studies from Pakistan were reported about the use of flora for phytoremediation. According to recent literature, 50 plant species from Pakistan are studied for remediation purposes. In this review, the potential of different plant species for phytoremediation from Pakistan has been discussed along with their comparison to other countries to relate future perspectives.

Diazotrophs-assisted phytoremediation of heavy metals: a novel approach

Heavy metals, which have severe toxic effects on plants, animals, and human health, are serious pollutants of the modern world. Remediation of heavy metal pollution is utmost necessary. Among different approaches used for such remediation, phytoremediation is an emerging technology. Research is in progress to enhance the efficiency of this plant-based technology. In this regard, the role of rhizospheric and symbiotic microorganisms is important. It was assessed by enumeration of data from the current studies that efficiency of phytoremediation can be enhanced by assisting with diazotrophs. These bacteria are very beneficial because they bring metals to more bioavailable form by the processes of methylation, chelation, leaching, and redox reactions and the production of siderophores. Diazotrophs also posses growth-promoting traits including nitrogen fixation, phosphorous solubilization, phytohormones synthesis, siderophore production, and synthesis of ACC-deaminase which may facilitate plant growth and increase plant biomass, in turn facilitating phytoremediation technology. Thus, the aim of this review is to highlight the potential of diazotrophs in assisting phytoremediation of heavy metals in contaminated soils. The novel current assessment of literature suggests the winning combination of diazotroph with phytoremediation technology.

Biodegradation of chlorpyrifos by bacterial genus Pseudomonas

Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico‐chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6‐trichloro‐2‐pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO2, H2O, and NH3. Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS‐1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides.

Recent progress in bioethanol production from lignocellulosic materials: A review

ABSTRACT Natural energy sources like petrol and diesel are going to be diminished in the coming future which will lead to increase in the prices and demands of fossil fuels. Therefore, it is important to find a sustainable alternate of fossil fuels. Bioethanol is one of the alternatives, which is produced from different feedstocks including sugar-based, starch-based and lignocellulose-based materials through fermentation. Since sugar-based (sugar cane and sugar beet) and starch-based (corn) materials are sources of staple food, therefore, research on lignocellulosic materials for bioethanol production is a subject of recent studies. Ethanol production from lignocellulosic materials involves different steps, such as pretreatment, hydrolysis, followed by fermentation process and finally ethanol purification. In this review, we have summarized the recent progresses in bioethanol production and processing from lignocellulosic materials.

Phyto-Extraction of Nickel by Linum usitatissimum in Association with Glomus intraradices

Plants show enhanced phytoremediation of heavy metal contaminated soils particularly in response to fungal inoculation. Present study was conducted to find out the influence of Nickel (Ni) toxicity on plant biomass, growth, chlorophyll content, proline production and metal accumulation by L. usitatissimum (flax) in the presence of Glomus intraradices. Flax seedlings of both inoculated with G. intraradices and non-inoculated were exposed to different concentrations i.e., 250, 350 and 500 ppm of Ni at different time intervals. Analysis of physiological parameters revealed that Ni depressed the growth and photosynthetic activity of plants. However, the inoculation of plants with arbuscular mycorrhizae (G. intraradices) partially helped in the alleviation of Ni toxicity as indicated by improved plant growth under Ni stress. Ni uptake of non- mycorrhizal flax plants was increased by 98% as compared to control conditions whereas inoculated plants showed 19% more uptake when compared with the non-inoculated plants. Mycorrhizal plants exhibited increasing capacity to remediate contaminated soils along with improved growth. Thus, AM assisted phytoremediation helps in the accumulation of Ni in plants to reclaim Ni toxic soils. Based on our findings, it can be concluded that the role of flax plants and mycorrhizal fungi is extremely important in phytoremediation.

Influence of endophytic Bacillus pumilus and EDTA on the phytoextraction of Cu from soil by using Cicer arietinum

ABSTRACT In developing countries, soil contamination with metals is ubiquitous, which poses a serious threat to the ecosystem. The current study was designed to screen out the nested belongings of Cicer arietinum plants and Bacillus pumilus (KF 875447) in extracting copper (Cu) from contaminated soils. A pot experiment was executed by growing C. arietinum seedlings either inoculated with B. pumilus or uninoculated along with the application of 5 mM ethylenediaminetetraacetic acid (EDTA). Plants were subjected to three different concentrations of Cu (250, 350, and 500 ppm) for 48 days. An increase in Cu uptake was observed in C. arietinum plants inoculated with B. pumilus as compared to uninoculated ones. C. arietinum exhibited improved values for different growth parameters in the presence of B. pumilus, that is, root length (37%), shoot length (31%), whole plant fresh as well as (45%) dry weight (27%), and chlorophyll contents (32%). More than 70% of tolerance index (TI) was observed for plants at 500 ppm Cu treatment. Addition of B. pumilus and EDTA significantly increased metal uptake by C. arietinum up to 19 and 36%, respectively, while the application of B. pumilus and EDTA in combination increased metal accumulation by 41%. The calculated bioaccumulation and translocation factor (TF) revealed that C. arietinum possess phytoextraction potential for Cu, and this ability is significantly improved with application of B. pumilus and EDTA amendments.

FIRST REPORT OF RHIZOPUS ORYZAE CAUSING FRUIT ROT OF CITRUS MEDICA L. IN PAKISTAN

Citrus medica, commonly known as Otroj, is a member of the family Rutaceae that contains important nutrients (Al-Yahya et al., 2013). In a survey from September to October 2014, C. medica fruits showing brown, wrinkled, sunken and dark lesions and decayed tissues that extended into the center, were collected in Islamabad Capital Territory (Pakistan). As the disease progressed, the fruits rotted severely and collapsed. A fungus isolated from diseased fruits on Sabouraud dextrose agar (SDA) mediium had an initially white mycelium that, over time, turned grayish black with a net-like structure. The reverse of the colonies was light brown. This fungus resembled morphologically Rhizopus oryzae and was comprised of sporangia, apophysis, sporangiophores and rhizoids. It grew by extending the hyphae along the surface of the substrate and penetrated it with rhizoids. The ultimate identification as R. oryzae was achieved based on the comparative molecular analysis of the ITS1, ITS4 and 18SrRNA sequences. In particular, BLAST analysis revealed 100% similarity with R. oryzae strain LXM4 (GenBank accession No. GQ220706.1) and 99% similarity with R. oryzae isolate F750 (KM249084.1), respectively. To prove Koch’s postulates, mycelial plugs (5-mm diameter) were placed on superficially wounded surface-sterilized C. medica fruits, all of which developed lesions after seven days at 27°C. R oryzae was consistently re-isolated from symptomatic fruits. No infection was observed on wounded but non-inoculated controls. To our knowledge, this is the first report of R. oryzae causing fruit rot of C. medica in Pakistan.

Paddy Land Pollutants and Their Role in Climate Change

Climate change is one of the biggest concerns because its potential impact on human life is severe. The contribution ratio of CH4, CO2, and N2O to global warming would be high even if their emission rates are small. Paddy lands may become polluted by the aggregation of several pollutants, i.e., organic and inorganic fertilizers; discharges from the quickly extending industrial territories; use of manure, and organic solid waste; and wastewater irrigation system. Paddy lands are considered to be a major source of anthropogenic greenhouse gas (GHG) emissions through methanogenesis (a process of methane production), a microbial process that is strictly restricted to paddy fields. Overall 90% of rice land is at least temporarily flooded and produces GHGs at higher rates. The production of N2O in soils occurs during nitrification, denitrification, and microbiological processes. A positive relationship was found between the climate change and N fertilizer application with N2O emissions from paddy lands. The use of N fertilizer also stimulates and influences the CH4 emission flux between paddy land and atmosphere. The impact of biochar amendments on the CH4 emission expanded by 35.16–40.62% in paddy fields. It is of incredible concern worldwide that gaseous outflows from management of organic solid waste add to local and worldwide scale ecological procedures, for example, eutrophication, fermentation, and climate change. CH4 is generated from the disintegration of organic matter (OM) in anaerobic conditions by methanogens. Soil OM is the most well-known constraining element for methanogenesis in paddy fields. OM obtained from three primary sources: animal fertilizer, green manure, and crop deposits. The amendment of OM, for example, rice deposits and compost application, prompts expanding CH4 outflows because of anaerobic decay and results in climate change.

First report of Rhizopus oryzae causing fruit rot of yellow oleander in Pakistan

Abstract Yellow oleander (Thevetia peruviana J.) is grown as an ornamental shrub in Pakistan. A severe rot was observed on fruit of yellow oleander in different areas of Islamabad, Wah and Taxila, Pakistan during 2014–2015. The causal agent was isolated from infected fruits and its pathogenicity was confirmed from inoculation experiments. The pathogen was identified as Rhizopus oryzae on the basis of its morphological features and rDNA sequence. Blast analysis revealed 99–100% similarity with R. oryzae. This is the first report of rot caused by R. oryzae on yellow oleander.

FIRST REPORT OF FUSARIUM ROT CAUSED BY FUSARIUM OXYSPORUM ON GRAPEFRUIT IN PAKISTAN

During year 2014-2015, severe infection was observed on grapefruit plants in Rawalpindi and Islamabad Capital Territory (ICT), Pakistan. Symptoms appeared as brown, oval or round spots, with varying sizes ranging from small spot (5 mm) to decay of the entire fruit. Twenty-five infected fruits were collected, surface-sterilized and 3-mm-diameter sections were placed on potato dextrose agar (PDA) medium at 26°C. After 4 days, the mycelia of the isolates were delicate, creamy white and pink or purple tinge, and their margins slightly lobed or smooth. Microconidia were single, oval to reniform and monophialides type. Moon crest shape macroconidia were produced in sporodochium with multiseptum. Short aerial conidiophores were unbranched, producing one-cell conidia in false head (Hussain et al., 2012). The microscopic structure was similar to that of Fusarium oxysporum. Molecular identification of pathogen was achieved by its rDNA sequence analysis. Genomic DNA was extracted from a single pure colony of fungus and its 18S rDNA region was amplified (White et al., 1990). Sequence analysis showed 99% similarity with Fusarium oxysporum strain NSF2 18S ribosomal RNA gene, partial sequence (KR611565.1). This sequence was deposited in NCBI database (KX384665). To prove Koch’s postulates, ten fruit were spray inoculated with isolated fungal conidial suspension (1 × 105 spores/ml of water). All inoculated fruit showed similar symptoms. No spots or lesions were observed on controlled fruits. F. oxysporum was re-isolated from the diseased fruits. To our knowledge this is the first report of F. oxysporum causing fruit rot on grapefruit.