Landfill leachate a new threat to water quality: a case study from the Temperate Himalayas.

Landfills are commonly seen as the most cost-efficient and practical approach to waste management in various regions around the world. Nonetheless, the infiltration of hazardous materials from poorly managed dumping sites remains a significant environmental issue in most developing countries such as India. Leachate serves as a prominent point source of contamination in many environmental media like soil, groundwater, and surface water around the world. So the prime issues humans are experiencing are associated with water quality. Thus, the investigation was undertaken to assess the impact of leachate from the Achan landfill on surface water quality in the Temperate Himalayas. Monitoring was done during in all four seasons, viz., spring, summer, autumn, and winter. Among the sites, the leachate outflow site was found to have the highest mean value of pH (7.95), EC (2.16 dS/m), total nitrogen (2.64 mg/l), P (4.75 mg/l), K (1.41 mg/l), Ca (107.45 mg/l), Mg (54.93 mg/l), Zn (0.8 mg/l), Fe (1.78 mg/l), Cu (0.66 mg/l), Mn (0.81 mg/l), BOD (21.47 mg/l), COD (66.24 mg/l), temperature (14.22 °C), turbidity (14.29 NTU), while lowest mean values of all parameters were recorded at control site. Among the seasons, summer season was found to have maximum value of pH (7.9), EC (2.36 dS/m), total nitrogen (2.54 mg/l), P (4.0 mg/l), K (0.89 mg/l), Ca (85.94 mg/l), Mg (43.91 mg/l), Fe (1.4 mg/l), Cu (0.52 mg/l), Mn (0.64 mg/l), BOD (22.82 mg/l), COD (65.87 mg/l), temperature (18.99 °C), and turbidity (8.49 NTU). The maximum mean value of Zn (0.66 mg/l) was recorded during winter season, while other parameters were found to be minimum during winter season. From this study, we concluded that a decreasing trend was observed during all the seasons in the concentration of all physico-chemical parameters with an increase in distance from the landfill. So it is recommended that the leachate should be treated at the source before disposing into the water body and the landfill should be lined properly to prevent the entry of leachate into water sources.

Bacterial Endophyte Community Dynamics in Apple (Malus domestica Borkh.) Germplasm and Their Evaluation for Scab Management Strategies.

The large genetic evolution due to the sexual reproduction-mediated gene assortments and propensities has made Venturia inaequalis (causing apple scab) unique with respect to its management strategies. The resistance in apple germplasm against the scab, being controlled for by more than fifteen genes, has limited gene alteration-based investigations. Therefore, a biological approach of bacterial endophyte community dynamics was envisioned across the apple germplasm in context to the fungistatic behavior against V. inaequalis. A total of 155 colonies of bacterial endophytes were isolated from various plant parts of the apple, comprising 19 varieties, and after screening for antifungal behavior followed by morphological, ARDRA, and sequence analysis, a total of 71 isolates were selected for this study. The alpha diversity indices were seen to fluctuate greatly among the isolation samples in context to microflora with antifungal behavior. As all the isolates were screened for the presence of various metabolites and some relevant genes that directly or indirectly influence the fungistatic behavior of the isolated microflora, a huge variation among the isolated microflora was observed. The outstanding isolates showing highest percentage growth inhibition of V. inaequalis were exploited to raise a bio-formulation, which was tested against the scab prevalence in eight apple varieties under controlled growth conditions. The formulation at all the concentrations caused considerable reductions in both the disease severity and disease incidence in all the tested apple varieties. Red Delicious being most important cultivar of the northwestern Himalayas was further investigated for its biochemical behavior in formulation and the investigation revealed different levels of enzyme production, chlorophyll, and sugars against the non-inoculated control.