Effects of 5-Aminolevulinic Acid (ALA) on Zinnia hybrida Growth and Phytoremediation Effects in Oil-Contaminated Soil

In this study, we compared plant height, weight, soil TPH concentration, and soil DHA level after 18 weeks of Zennia hybrida cultivation with four different concentrations of 5-Aminolevulinic acid (ALA)-based liquid fertilizer: 1500-fold, 5000-fold, and 8000-fold dilutions, along with a non-treatment control of diluted ALA. The plants of ALA-treated were significantly taller than the non-treatment control. The plants of ALA-treated plants were higher in shoot fresh weight, shoot dry weight, and root dry weight than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold dilution was significantly highest in shoot fresh weight, shoot dry weight, and root dry weight. ALA-treated plants were lower in the soil Total Petroleum Hydrocarbon (TPH) concentration than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold was significantly lowest in the TPH concentration. In addition, ALA-treated plants were higher in the soil dehydrogenase activity (DHA) than the non-treatment control. The plot of ALA-based liquid fertilizer with the 5000-fold was significantly highest in the TPH concentration. This study indicated that ALA-applied zinnia-grown oil-contaminated soil is more effective than not. The remediation in oil-contaminated soil with ALA-based liquid fertilizer is more effective than the non-treatment control;furthermore, ALA application with 5000-fold dilution was most suitable in oil-contaminated soil among other plots.

Improvement of phosphorus uptake,phosphorus use efficiency,and grain yield of upland rice(Oryza sativa L.)in response to phosphate-solubilizing bacteria blended with phosphorus fertilizer

Phosphorus(P)limitation in soil is a major concern for crop productivity.However,the use of chemical fertilizer is hazardous to the environment and costly.Therefore,the use of phosphate-solubilizing bacteria(PSB)is an eco-friendly approach for a sustainable agricultural system.In the present study,a field trial was conducted for two consecutive years to study the effects of three PSB strains isolated,Bacillus licheniformis,Pantoea dispersa,and Staphylococcus sp.,with different P fertilizer rates on P uptake,P use efficiency(PUE),and grain yield of rice.The activities of soil enzymes were also studied in relation to PSB treatments.Comparative analysis of the yield and biochemical parameters revealed that inoculation of PSB consortium could reduce almost 50%of the recommended P dose in rice cultivation.Three PSB strains in combination with 50%P dose was most effective and showed the highest increases in P uptake and PUE as compared to the uninoculated control.Moreover,the PSB consortium combined with 50%P dose contributed to 50.58%and35.64%yield increases compared to the uninoculated control for 2018 and 2019,respectively.Significant increases in the activities of soil dehydrogenase,alkaline phosphatase,and acid phosphatase were also recorded under PSB treatment.