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Larvicidal and repellent activity of N-methyl-1-adamantylamine and oleic acid a major derivative of bael tree ethanol leaf extracts against dengue mosquito vector and their biosafety on natural predator
2022
Chellappandian, Muthiah | Senthil-Nathan, Sengottayan | Karthi, Sengodan | Vasantha-Srinivasan, Prabhakaran | Kalaivani, Kandaswamy | Hunter, Wayne Brian | Ali, Ajmal M. | Veerabahu, Chockalingam | Elshikh, Mohamed Soliman | Al Farraj, Dunia A.
Aegle marmelos (L.) Correa belongs to the family Rutaceae is generally known as “bael fruit tree” occuring across the south Asian countries. The current investigation screened the main derivatives from crude ethanolic extracts of the Bael tree leaf and evaluated activity effects on the larvae and adults of Aedes aegypti (L.) Dengue vector mosquito and a non-target aquatic predator. The GC-MS results showed that the peak area was found to be profound in N-methyl-1-adamantaneacetamide (N-M 1a) followed by oleic acid (OA) with 63.08 and 11.43% respectively. The larvicidal activity against the fourth instar larvae and the crude Ex-Am showed prominent mortality rate (93.60%) at the maximum dosage of 100 ppm. The mortality rate of N-M 1a and OA was occurred at 10 ppm (97.73%) and 12 ppm (95.4%). The repellent activity was found to be prominent at crude Ex-Am (50 ppm) as compared to the pure compounds (N-m 1a and OA) with maximum protection time up to 210 min. The non-target screening of Ex-Am, N-M 1a, and OA on mosquito predator Tx. splendens showed that they are scarcely toxic even at the maximum dosage of 1000 ppm (34.13%), 100 ppm (27.3%), and 120 ppm (31.3%) respectively. Thus, the present investigation clearly proved that the crude Ex-Am and their major derivatives Nm 1-a and OA showed their acute larval toxicity as well as potential mosquito repellent against the dengue mosquito and eco-safety against the mosquito predator.
Показать больше [+] Меньше [-]Sewage Sludge Usage in Agriculture: a Case Study of Its Destination in the Curitiba Metropolitan Region, Paraná, Brazil
2014
Bittencourt, Simone | Serrat, Beatriz Monte | Aisse, Miguel Mansur | Gomes, Debora
The agricultural destination of sewage sludge promotes the return of organic matter and nutrients to the soil, prevents contamination and degradation of hydric resources, and contributes to food and fiber production. In Brazil, the Resolution of the National Environment Council (Conama 375/06) and in the State of Paraná the Resolution of the State Environment Cabinet (Sema 021/09) established criteria and procedures for agricultural use of sewage sludge seeking to avoid risk to public health and the environment. This case study attempts to present the results of the destination of the sludge generated in the Sludge Management Units (SMU) in Curitiba Metropolitan Region (CMR), State of Paraná, Brazil from 2007 to 2010. Data analysis of agronomic parameters and inorganic substances (metals) of 99 batches of sewage sludge destined for agricultural use, based on 239 agronomic projects, was performed. The comparison of the characteristics of the batches generated in anaerobic and aerobic SMUs of CMR was also conducted. During the study, 88,166 t of sludge (33,404 dry tons) were destined for 2,288 ha of agricultural areas. The sludge provided 88 % of the lime, 74 % of N, 73 % of P₂O₅, and 35 % of K₂O for fertilizing the corn, soybean, bean, oat, wheat, green manure, and in the implementation and postharvest of stone fruit trees. The 80 benefited farmers reduced expenses with fertilizers and limestone, saving an average of US$813.45 per ha.
Показать больше [+] Меньше [-]The role of leaf litter as a protective barrier for copper-containing pesticides in orchard soils
2021
Schoffer, Jorge Tomás | Antilén, Mónica | Neaman, Alexander | Díaz, María Francisca | de la Fuente, Luz María | Urdiales, Cristian | Ginocchio, Rosanna
This study assessed the capacity of leaf litters to adsorb copper ions applied as a copper-based pesticide. Leaf litters of two fruit tree species with different lignin/N ratios were examined to determine their protective role against the incorporation of Cu into soil. A leaf litter Cu-adsorption capacity assay and a degradation assay were performed using table grape (lignin/N = 2.35) and kiwi (lignin/N = 10.85) leaf litters. Table grape leaf litter had a significantly (p = 0.001) higher Cu-adsorption capacity (15,800 mg kg⁻¹) than kiwi leaf litter (14,283 mg kg⁻¹). Following leaf litter degradation, significant differences (p = 0.011) were observed in the release of Cu from Cu-enriched leaf litter into soil, showing that kiwi litter has a greater protective effect against the incorporation of Cu into soil, regardless of the amount of Cu applied. This protective role is reflected in a significantly higher (p = 0.015) Cu concentration in table grape soil (41.71 ± 2.14 mg kg⁻¹) than in kiwi soil (35.87 ± 0.69 mg kg⁻¹). Therefore, leaf litter with higher lignin/N ratio has greater protective role against copper incorporation into soil.
Показать больше [+] Меньше [-]Dispersion, persistence, and stability of the biocontrol agent Penicillium frequentans strain 909 after stone fruit tree applications
2019
Guijarro, Belen | Larena, Inmaculada | Vilanova, Laura | Torres, Rosario | Balsells-Llauradó, Marta | Teixidó, Neus | Melgarejo, Paloma | De Cal, Antonieta
The capacity of dispersion, persistence, and stability from biocontrol agents is essential before these organisms can be developed into a commercial product. Interactions that microorganisms establish with stone fruit trees may be beneficial in the exploitation of trees in agriculture as crop production. The natural background levels of Penicillium frequentans strain 909 dispersion, persistence, and stability were assessed after tree applications and postharvest conditions. A fingerprinting-based approach to trace genetic stability of P. frequentans along stored time and its release in the field was developed. P. frequentans was successfully traced and discriminated. This strain was dispersed well in treated trees, persisting in the ecosystem up to 2 weeks and staying genetically stable after 36 months of storage. However, the dispersal of P. frequentans was very limited on around untreated trees and soil. P. frequentans dispersed randomly into the air, and its presence reduced from the first day to disappear completely at 15–21 days after application. Great losses of P. frequentans and its increased dispersal in open field conditions probably resulted from rainfall. Biological control strategies with Pf909 were discussed.
Показать больше [+] Меньше [-]Effectiveness of rodenticides for managing invasive roof rats and native deer mice in orchards
2014
Baldwin, Roger A. | Quinn, Niamh | Davis, David H. | Engeman, Richard M.
Roof rats (Rattus rattus) and deer mice (Peromyscus maniculatus) are occasional pests of nut and tree fruit orchards throughout California and in many other parts of the USA and beyond. In general, the most practical and cost-effective control method for rodents in many agricultural environments is the use of rodenticides (toxic baits), but little or no information exists on the efficacy of current rodenticides in controlling roof rats and deer mice in orchards. Therefore, our goals were to develop an index of rodent activity to monitor efficacy of rodenticides and to subsequently test the efficacy of three California Department of Food and Agriculture rodenticide baits (0.005 % chlorophacinone treated oats, 0.005 % diphacinone treated oats, and 0.005 % diphacinone wax block) to determine their utility for controlling roof rats and deer mice in agricultural orchards. We determined that a general index using the number of roof rat photos taken at a minimum of a 5-min interval was strongly correlated to the minimum number known estimate of roof rats; this approach was used to monitor roof rat and deer mouse populations pre- and post-treatment. Of the baits tested, the 0.005 % diphacinone treated oats was most effective for both species; 0.005 % chlorophacinone grain was completely ineffective against roof rats. Our use of elevated bait stations proved effective at providing bait to target species and should substantially limit access to rodenticides by many non-target species.
Показать больше [+] Меньше [-]Establishment of a constructed wetland in extreme dryland
2009
Tencer, Yoram | Idan, Gil | Strom, Marjorie | Nusinow, Uri | Banet, Dorit | Cohen, Eli | Schröder, Peter | Shelef, Oren | Rachmilevitch, Shimon | Soares, Ines | Gross, Amit | Golan-Goldhirsh, Avi
Background, aim, and scope The project was set to construct an extensive wetland in the southernmost region of Israel at Kibbutz Neot Smadar (30°02′45″ N and 35°01′19″ E). The results of the first period of monitoring, summary, and perspectives are presented. The constructed wetland (CW) was built and the subsequent monitoring performed in the framework of the Southern Arava Sustainable Waste Management Plan, funded by the EU LIFE Fund. The specific aims were: (1) To end current sewage disposal and pollution of the ground, the aquifer, and the dry river bed (wadi) paths by biologically treating the sewage as part of the creation of a sustainable wetland ecosystem. (2) Serve as an example of CW in the Negev highlands and the Arava Valley climates for neighboring communities and as a test ground for plants and building methods appropriate to hyper arid climate. (3) Serve as an educational resource and tourist attraction for groups to learn about water reuse, recycling, local wildlife and migrating birds, including serving the heart of a planned Ecological-Educational Bird Park. This report is intended to allow others who are planning similar systems in hyper arid climates to learn from our experience. Materials and methods The project is located in an extreme arid desert with less than 40 mm of rain annually and temperature ranges of −5°C to +42°C. The site receives 165-185 m³ of municipal and agricultural wastes daily, including cowshed and goat wastes and winery outflow. Results The CW establishment at Neot Smadar was completed in October 2006. For 8 months, clean water flowed through the system while the plants were taking root. In June 2007, the wetland was connected to the oxidation pond and full operation began. Because of seepage and evaporation, during the first several months, the water level was not high enough to allow free flow from one bed to the next. To bed A, the water was pumped periodically from the oxidation pond (Fig. 1) and from there flowed by gravitation through the rest of the system. The initial results of the monitoring are promising. In nearly all measurements, the system succeeded as expected to reduce levels of contaminants at least to the level acceptable for irrigating fruit trees and often to the level of unlimited irrigation. The introduction of the plants in the system and their physiological performance were evaluated and were found to correlate well to the quality of water in the various beds. Discussion It should be said at the outset that evaluation of the performance of a CW system is a long-term process. Thus, the main aim of this report is to present the problems, difficulties, preliminary results, and concepts concerned with the first stage of establishment of CW in an extremely dry region. Conclusions The CW system was designed to dispose of municipal and agricultural wastes in a way that not merely reduces pollution, but adds to environmental quality by creating accessible parkland for local residents and tourists. Several factors affected the performance of the system at the initial stages of operation: ecological balance between microbes and plants, big seasonal variations, seepage and evaporation reduced the flow in the initial operation of the system. Despite the initial difficulties, the quality of water coming out the system is acceptable for irrigation. Recommendations and perspectives The CW can function well under extreme dryland conditions. The oxidation pond was the major source of evaporation and bad odors. Therefore, alternatives to the oxidation pond are needed. Cost effectiveness of the system still has to be evaluated systematically.
Показать больше [+] Меньше [-]Degradation of tetracyclines in manure-amended soil and their uptake by litchi (Litchi chinensis Sonn.)
2019
Shi, Hui | Bai, Cuihua | Luo, Donglin | Wang, Wei | Zhou, Changmin | Meharg, Andrew A. | Yao, Lixian
The environmental and human health risk posed by veterinary antibiotics is of global concern. Antibiotic uptake by herbal plants has been studied, but little is known about perennial woody fruit crops. Litchi (Litchi chinensis Sonn.), a longevial fruit tree, is routinely fertilized with animal manure and, therefore, may be at risk of antibiotic uptake into its fruits. This study investigated the degradation of chlortetracycline and doxycycline present in manure used to amend orchard soil, and their subsequent assimilation by litchi plant, as affected by manure application rate. The results show that half-lives of chlortetracycline and doxycycline in soil were decreased by increased manure rate, with an average of 27 and 59 days, respectively. Chlortetracycline was readily transported to litchi shoots and increased with the growth of litchi plants. Doxycycline predominantly remained in the roots, and underwent growth dilution in the plants. The two tetracyclines could not be detected in fruits from litchi trees when applied with manures, at various rates, over 2 years. For litchi, chlortetracycline may pose human health risk through manure application, but doxycycline is unlikely to do so. Long-term field experiments are required to monitor antibiotic accumulation in fruits of perennial fruit trees fertilized with animal manure.
Показать больше [+] Меньше [-]Essential oils from Algerian species of Mentha as new bio-control agents against phytopathogen strains
2018
Benomari, Fatima Zahra | Andreu, Vanessa | Kotarba, Jules | Dib, Mohammed El Amine | Bertrand, Cédric | Muselli, Alain | Costa, Jean | Djabou, Nassim
Chemical composition and antifungal activity of essential oils of Algerian Mentha species were studied. Chemical compositions of different Mentha species oils (Mentha rotundifolia, M. spicata, M. pulegium, and M. piperita) were investigated by capillary GC and GC/MS, and their antifungal activities were evaluated by means of paper disc diffusion method and minimum inhibitory concentration (MIC) assays. In total, 98 components from all Mentha species were identified. All oils were rich in monoterpene-oxygenated components. In addition, we reported fumigant antifungal activity of Algerian Mentha essential oils against four fungi: Botrytis cinerea, Penicillium expansum, Monilinia laxa, and M. fructigena. All oils demonstrated very good inhibition especially against B. cinerea, M. laxa, and M. fructigena. Both Monilinia fungi were extremely sensitive to all Algerian Mentha oils, which suggests that Mentha essential oils have the potential to be used as bio-pesticides to protect fruit trees, such as apple and pear trees, and provides an alternative to chemical pesticides.
Показать больше [+] Меньше [-]Temporal variation in quality of groundwater from a shallow well in an agricultural (apple orchard) area
2004
Fukuzawa, H.(Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Akaoka, T. | Ozawa, H.