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The biodegradation and biosorption efficiency of an indigenous siderophores-producing bacterial community on azo dyes with immobilization in chitosan beads was evaluated in this study. 13 bacterial strains were isolated from textile wastewater streams. The bacterial strains were tested for the production of siderophores as well as their ability to decolorize toxic azo dyes in aqueous solution. Both qualitatively and quantitatively, all of the strains displayed high siderophores productivity. Furthermore, they displayed remarkable decolorization efficiency for azo dyes (Acid Black 1 and Reactive Black 5) in both free and immobilized form. The immobilization process was found not only to enhance the decolorization but also the degradation of azo dyes by the bacterial isolates. In a SEM micrograph, bacterial strains were immobilized, and the pores in chitosan bead to be trapped and adsorbed for dyes from synthetic wastewater. The extent of dye compounds degradation were examined using UV–visible and FTIR spectrophotometers on treated water samples and dye absorbed beads. After 72 h of incubation, the UV–visible analysis revealed that the bacterial community could significantly reduce both azo dyes in wastewater by 90% at 300 mgL−1 dyes initial concentration. FTIR study confirmed the bonds of these dyes were broken to form less toxic chemicals via the bacterial community immobilized in chitosan beads. The immobilized bacterial community thus demonstrated effective approach of azo dye biosorption and biodegradation.

Landlords and cultivators of watermelon ( Citrullus lanatus) and several other types of melons ( Cucumis melo var. Cantalupensis, Cucumis melo var. Reticulatus, Cucumis melo var. Cucumis melo Inodorusvar, etc.) complained about soil degradation due to cultivation of melons without judicious use of pesticides. Conducting a field survey on the use of pesticides and the prevalence of pesticide residues in the soil of melon-cultivated areas, the study investigates the authenticity of such claims and figures out the actual reasons for such land degradation. The survey was carried out on 150 farmers from 30 villages in Kyaukse, Myitthar and Tada U Township in Mandalay division of Myanmar. The survey captures information on pesticide-related awareness, attitudes and practices and identifies possible health and environmental risks. The usage, storage and handling of pesticides by most of the respondents were found not safe, and knowledge on the adverse effects of pesticides on health, crops and the environment was found to be inadequate. The findings have indicated the potential risk of soil degradation. It appears that lack of cooperation among the government, non-governmental organisations (NGO), private sector stakeholders and farmers is the key weakness for improving agricultural practices adopted by farmers. Enhancing the awareness, changing the attitudes and improving the practices of the farmers regarding the use of pesticides may be the key step towards addressing this issue.

This study was aimed to determine the degradation potential of indigenous fungi isolated from glyphosate contaminated soil. A total number of 10 fungal strains have been isolated and screened their tolerance level against various concentrations of glyphosate (200, 400, 600, 800 and 1000 ppm).These strains were also screened for laccase activity. Only two strains 5p and 6m showed laccase activity and they are characterized, identified and selected for myco-remediation experiment. Due to its macro- and microscopic morphology of mycelia and the molecular similarity, the isolate 5p was identified as Trichoderma harzianum and the isolate 6m as Aspergillus Aiger. 1000ppm of Glyphosate disappeared rapidly in mineral salt liquid media by T.harzianum 78.1% and A.niger 87.3%. Glyphosate almost disappeared by T. harzianum 67.1 % and A. niger 67.2% in the water medium. Based on present findings, these fungal strains can be recommended as potentially effective to protect the environment from the herbicide residues.