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The Passive Environmental Effect of the Fungicide Benomyl on Soil Promoting Bacteria and Concentration of Some Important Soil Elements
2024
Zaid Raad Abbas, Aqeel Mohammed Majeed Al-Ezee, Sawsan Hassan Authman and Maan Abdul Azeez Shafeeq
Loam examples were gathered through the 2020-2021 rising periods, and the following measurements were made: Viable bacterial count by reducing root colonization. The outcomes of reviewing the impact of the fungicide Benomyl on development and viable microflora count revealed that the highest microbial count was in Al-Madaein 80 ×103 CFU/mL was recorded ., and the lowest count was 60 ×103 CFU/mL for the Aushtar area, The microbial viable count values for the affected microorganisms with Benomyl were decrease to 27×103 and 65 × 103 CFU/mL respectively. Those consequences specify that Benomyl has a robust choosiness contrary to microflora, especially when compared to the benomyl effect as folded dose, the microflora l count decreases to 25 ×103 CFU /mL in the Aushtar area and increases to 60 ×103 CFU/mL in Al-Madaein area. Whereas the study estimated the level of eight elements in soil (Mn, Fe, Cu, Zn, NO3, P, K, and NH4) cultured with Cyperus rotundus L. Which mentioned the effect of benomyl on these levels after three days of treatment. Mn concentration ranged between 5.96 to 9.11 ppm, while after fungicide benomyl, it decreased to 5.63 -6.53 ppm similar results were observed for other elements. The highest affected element was Mn in the Aushtar area. Those consequences designate that Benomyl has a stout fussiness in contrast to soil nutrients. The greatness of benomyl impacts on loam ingredients and procedures were minor, qualified to impact on mycorrhizal root foundation (reduction through benomyl).
اظهر المزيد [+] اقل [-]Rhizosphere Phytoremediation with Cyperus rotundus for Diesel-Contaminated Wetlands
2016
Hou, Yunyun | Liu, Xiaoyan | Zhang, Xinying | Hu, Xiaoxin | Cao, Liya
Diesel spills may considerably damage the sensitive coastal wetlands along Huangpu River, Shanghai, China. In this experiment, Cyperus rotundus, a dominant coastal marsh plant, was cultured in diesel-contaminated soils at concentrations of 0, 1000, 5000, 10,000, 15,000 and 20,000 mg kg⁻¹ to investigate its phytoremediation potential. In this study, plant biomass, removal characteristic of diesel, redox potential, and activities of urease, dehydrogenase, and polyphenoloxidase in soils were determined after 50-day pot experiments. The results demonstrated that soils planted with Cyperus rotundus had significantly less diesel than did unplanted soils. The residual concentrations of alkanes in soils at 10,000 mg kg⁻¹ after 50 days showed that 52.9–92.0 % of Fraction a (C₁₄–C₁₉) and 47.8–64.4 % of Fraction b (C₂₀–C₂₇) were removed in unplanted soils, while more than 90 % of both Fractions a and b were removed in planted soils. The peak value of urease and dehydrogenase activities was at 15,000 mg kg⁻¹ of diesel-contaminated concentration; however, the peak value of polyphenoloxidase activity appeared at 10,000 mg kg⁻¹. It was deduced that the diesel concentration between 10,000 and 15,000 mg kg⁻¹ might be a limit which Cyperus rotundus could tolerate diesel pollution.
اظهر المزيد [+] اقل [-]Chemical characterization, phytotoxic, and cytotoxic activities of essential oil of Mentha longifolia
2020
Singh, Narayan | Singh, Harminder Pal | Batish, Daizy Rani | Kohli, Ravinder Kumar | Yadav, Surender Singh
The present study assessed the phytotoxic and cytotoxic potential of the essential oil (EO) extracted from aboveground parts of Mentha longifolia (L.) Huds. Gas chromatography–mass spectrometry revealed 39 compounds constituting 99.67% of the EO. The EO was rich in monoterpenoids (mostly oxygenated monoterpenes), which accounted for 89.28% of the oil. The major components in EO were monoterpene ketones such as piperitone oxide (53.83%) and piperitenone oxide (11.52%), followed by thymol (5.80%), and (E)-caryophyllene (4.88%). The phytotoxic activities of EO were estimated against Cyperus rotundus, Echinochloa crus-galli, and Oryza sativa (rice) through pre- and post-emergence assays at concentrations ranging from 10 to 250 μg/ml and 0.5–5%, respectively. In pre-emergence assay, the phytotoxic effect of EO was most pronounced on C. rotundus, thereby significantly affecting percent germination, plantlet growth, and chlorophyll content. On the contrary, the impact was comparatively lesser on rice, with ~ 40% germination in response to 250 μg/ml of EO treatment. In the post-emergence assay, the spray treatment of EO caused a loss of chlorophyll and wilting in test plants, and subsequently affected the growth of plants, even leading to death in some cases. The cytotoxic activity of EO (at 2.5–50 μg/ml) was studied in meristem cells in onion (Allium cepa L.) root tips. EO exposure to the onion roots induced various chromosomal aberrations such as chromosomal bridges, c-mitosis, stickiness, vagrant chromosomes, etc., and negatively affected the mitotic index. At 50 μg/ml, EO treatment triggered the complete death of roots. The study concludes that M. longifolia EO has phytotoxic activities due to the mito-depressive effect, along with other physiological effects on target plants. Therefore, EO of M. longifolia could be developed into a novel bioherbicide for sustainable management of weeds in agricultural systems.
اظهر المزيد [+] اقل [-]Plant community characteristics and their responses to environmental factors in the water level fluctuation zone of the three gorges reservoir in China
2013
Zhang, Zhiyong | Wan, Chengyan | Zheng, Zhiwei | Hu, Lian | Feng, Kun | Chang, Jianbo | Xie, Ping
The annual water level regulating of the Three Gorges Reservoir prolonged the submerged duration (from 2 to 8 months) and resulted in the reversal of natural flood rhythms (winter submerged). These changes might alter plant community characteristics in the water level fluctuation zone (WLFZ). The aim of this study was to determine the plant community characteristics in the WLFZ and their responses to the environmental factors (i.e., annual hydrological regulation, topographic characteristics, soil physical properties and soil nutrients). The height, coverage, frequency and biomass of each plant species and the soil properties at each elevation zone (150, 155, 160, 165 and 170 m) were measured from March to September in 2010. Univariate two-factor analysis and redundancy analysis (RDA) were used to analyze the spatial and temporal variations of the community characteristics and identify the key environmental factors influencing vegetation. We found that 93.2 % of the species analysed were terrestrial vascular plants. Annual herbs made up the highest percentage of life forms at each altitude. The differences in the species number per square metre, the Shannon-Wiener diversity index and the biomass of vegetation demonstrated statistical significance with respect to sampling time but not elevation. The most dominant species at altitudes of 150, 155, 160, 165 and 170 m were Cynodon dactylon, Cyperus rotundus, Digitaria sanguinalis, Setaria viridis and Daucus carota, respectively. The concentrations of soil nutrients appeared to be the lowest at an altitude of 150 m, although the differences with respect to elevation were not significant. The results of the RDA indicated that the key factors that influenced the species composition of vegetation were elevation, slope, pH and the concentration of soil available phosphorus.
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