Methodology in Accelerated Biodegradation of Herbicides

1987 ◽  
Vol 1 (4) ◽  
pp. 333-340 ◽  
Author(s):  
Ravva V. Subba-Rao ◽  
Thomas H. Cromartie ◽  
Reed A. Gray
Keyword(s):  
Quantitative Measurement ◽  
Microbial Growth ◽  
Soil Microflora ◽  
Chemical Analyses ◽  
Untreated Soil ◽  
Accelerated Degradation ◽  
Field Soils ◽  
Potential Formation ◽  
Bacteria And Fungi ◽  
Additional Index

Accelerated biodegradation of herbicides in soils can be demonstrated in the laboratory either by treating soil samples with a herbicide under conditions favorable for microbial growth or by sampling field soils soon after herbicidal treatment. Quantitative measurement of accelerated degradation of thiocarbamates in field soils is complicated by the difficulty both of obtaining a proper untreated soil and of obtaining a representative sample by proper mixing of treated soil. Both bacteria and fungi degrade thiocarbamate herbicides, and examples of either class of organisms can be isolated by suitable selection and enrichment conditions. The enzymes involved in the initial steps of thiocarbamate biodegradation seem labile and have not been characterized. Studies of accelerated biodegradation of pesticides should measure the disappearance of the parent or active herbicide using chemical analyses or bioassays. Measuring accelerated biodegradation by determining metabolites (including CO2) is complicated by potential formation of other products, by incorporation of radioactivity into soil microflora, and by complex kinetics partly due to co-metabolism of the herbicide. Additional index words: EPTC, butylate.

Microflora of soil and wheat rhizosphere in a field following fumigation

Soil Research ◽  
1987 ◽  
Vol 25 (4) ◽  
pp. 491 ◽  
Author(s):  
K Sivasithamparam ◽  
GC MacNish ◽  
CS Fang ◽  
CA Parker
Keyword(s):  
Methyl Bromide ◽  
Sandy Loam ◽  
Fungal Species ◽  
Soil Microflora ◽  
Untreated Soil ◽  
Trichoderma Species ◽  
Wheat Rhizosphere ◽  
Aspergillus Glaucus ◽  
Initial Reduction ◽  
Bacteria And Fungi

Light sand and heavier sandy loam wheat-growing soils at Wongan Hills, W.A. were fumigated (2: 1 mixture of chloropicrin and methyl bromide) to study its effect on the soil microflora. In fumigated soil, numbers of bacteria and fungi, after an initial reduction, remained high and low, respectively, in comparison to untreated soil, throughout the period of study. In the fumigated soil Trichoderma species rapidly recolonized the soil, becoming the dominant fungus by 15 days and remaining so to the end of the experiment (145 days after fumigation). There was no difference in the total numbers of bacteria, actinomycetes or fungi in the rhizosphere of wheat grown in fumigated and non-fumigated soils. The numbers of some fungal species were lower in the rhizosphere of wheat grown in the fumigated soil, these included Aspergillus glaucus, A. fumigatus, Beauveria bassiana, Cladosporium cladosporoides, Embellisia tumida, Fusarium oxysporum, Penicillium patulum, P. tardum, Phialophora mutabilis and Trichoderma saturnisporurn. The only fungi found to be significantly higher in the rhizosphere of plants in fumigated soil were F. merismoides, T. koningii and T. viride.

Effects of potassium azide on soil microbial populations and soil enzymatic activities

1975 ◽  
Vol 21 (4) ◽  
pp. 565-570 ◽  
Author(s):  
W. D. Kelley ◽  
R. Rodriguez-Kabana
Keyword(s):  
Soil Enzyme ◽  
Soil Microflora ◽  
Microbial Populations ◽  
Bacterial Populations ◽  
Soil Microbial ◽  
Fungal Populations ◽  
Potassium Azide ◽  
Time Changes ◽  
Bacteria And Fungi ◽  
Microbial Numbers

Preplant applications of potassium azide (KN3) to pine nursery beds were evaluated for effect on the soil microflora and on soil enzyme activity where either plastic-sealing or water-sealing techniques were used. Two weeks after incorporation of azide (0–224 kg/ha), soil samplings revealed reduced populations of bacteria and fungi and a corresponding decline in invertase and amylase activities. These effects were proportionate to the amount of azide used and were more pronounced in plastic-sealed plots. Phosphatase activity was little affected. Five weeks after azide application, bacterial populations were higher in treated plots than in controls. Greater numbers of bacteria were recorded from plastic-sealed plots and highest populations coincided with plots receiving the highest rates of azide, regardless of the sealing technique. Fungal populations at this sampling were generally less in treated plots than in the controls, but were higher under plastic seal. At this time, changes in invertase and amylase activities did not correspond to increased microbial numbers. Sixteen weeks after applications of KN3, bacterial populations in treated plots did not differ significantly from controls, but remained higher in plastic-sealed than water-sealed plots. Fungal populations under plastic seal had changed little and remained significantly lower in treated water-sealed plots than in controls. The earlier recorded reduction in invertase and amylase activities was still evident at the final sampling.

Enhanced Soil Degradation of Butylate and EPTC in Nebraska Fields

1989 ◽  
Vol 3 (1) ◽  
pp. 24-29 ◽  
Author(s):  
Fred W. Roeth ◽  
Robert G. Wilson ◽  
Alex R. Martin ◽  
Patrick J. Shea
Keyword(s):  
Weed Control ◽  
Soil Degradation ◽  
Central Field ◽  
North Central ◽  
Herbicide Degradation ◽  
Accelerated Degradation ◽  
South Central ◽  
Field Soils ◽  
Enhanced Degradation

A survey to determine the frequency and weed control impact of enhanced degradation of butylate or EPTC in field soils receiving repeat applications of these herbicides was conducted in a sugarbeet and three corn growing areas of Nebraska. All seven of the sugarbeet field soils exhibited enhanced EPTC degradation. In the corn areas, none of the 13 north central and southeast field soils displayed accelerated degradation; however, 10 of the 16 south central field soils did. In south central Nebraska, 60% and 45% of the surveyed growers were dissatisfied with weed control from butylate or EPTC in 1983 and 1984, respectively, compared to 24% and none in other survey areas. Enhanced herbicide degradation and the presence of shattercane were the main reasons for the disparity among areas.

scholarly journals Holdover Inoculum of Pseudomonas syringae pv. alisalensis from Broccoli Raab Causes Disease in Subsequent Plantings

Plant Disease ◽  
2006 ◽  
Vol 90 (8) ◽  
pp. 1077-1084 ◽  
Author(s):  
N. A. Cintas ◽  
S. T. Koike ◽  
R. A. Bunch ◽  
C. T. Bull
Keyword(s):  
Pseudomonas Syringae ◽  
Brassica Rapa ◽  
Bacterial Blight ◽  
Laboratory Tests ◽  
Bacterial Population ◽  
Disease Incidence ◽  
Untreated Soil ◽  
Bacterial Populations ◽  
Field Soils ◽  
Over Time

Uniform plots of broccoli raab (Brassica rapa subsp. rapa) seedlings were inoculated with a rifampicin-resistant strain of Pseudomonas syringae pv. alisalensis, the causal agent of bacterial blight on crucifers, resulting in 100% disease incidence in mature plants. Diseased plants were incorporated into the soil at maturity and smaller replicated plots were replanted at various times after incorporation. Rifampicin-resistant fluorescent pseudomonads with rep-PCR profiles identical to P. syringae pv. alisalensis were isolated from lesions on plants grown in soil into which the first diseased crop was incorporated. Disease incidence declined in mature plants as the length of time between incorporation of the first planting and seeding of the replanted plots increased. Bacterial population levels in soil decreased over time and bacteria were no longer detectable 3 weeks after incorporation of the diseased crop. In laboratory tests, population levels of P. syringae pv. alisalensis decreased in untreated soil but not in autoclaved soil. Greenhouse studies demonstrated a direct correlation between population levels of P. syringae pv. alisalensis applied to soil and disease incidence in seedlings. However, the decline in bacterial populations in field soils did not wholly account for the decline in disease incidence with subsequent plantings.

scholarly journals New Diarylheptanoid from Garuga pinnata Roxb

2013 ◽  
Vol 61 (2) ◽  
pp. 131-134 ◽  
Author(s):  
Mst Taslima Khatun ◽  
M. Mahboob Ali Siddiqi ◽  
Al-Mansur MA ◽  
MH Sohrab ◽  
AFM Mustafizur Rahman ◽  
...  
Keyword(s):  
Brine Shrimp ◽  
Microbial Growth ◽  
Stem Bark ◽  
Diffusion Method ◽  
Gram Negative Bacteria ◽  
Disc Diffusion ◽  
Disc Diffusion Method ◽  
Gram Negative ◽  
Wide Range ◽  
Bacteria And Fungi

9´-Desmethylgaruganin I has been isolated from the dichloromethane extract of the stem bark of Garuga pinnata Roxb. The crude extract was screened for antimicrobial activity against a wide range of gram-positive and gram-negative bacteria and fungi by disc diffusion method and cytotoxicity by brine shrimp lethality bioassay. The dichloromethane extract showed moderate inhibitory activity to microbial growth and weak cytotoxicity having LC90 25.703?g-mL–1 DOI: http://dx.doi.org/10.3329/dujs.v61i2.17058 Dhaka Univ. J. Sci. 61(2): 131-134, 2013 (July)

scholarly journals Quantitative measurement of faecal blood loss: comparison of radioisotopic and chemical analyses.

1991 ◽  
Vol 44 (5) ◽  
pp. 391-394 ◽  
Author(s):  
M B Leahy ◽  
M J Pippard ◽  
M B Salzmann ◽  
M G Rinsler ◽  
R Hesp ◽  
...  
Keyword(s):  
Blood Loss ◽  
Quantitative Measurement ◽  
Chemical Analyses ◽  
Faecal Blood Loss

scholarly journals Differential effects of pesticides on soil microflora in cultivated soil of Indian rice field agro-ecosystems

2011 ◽  
Vol 3 (2) ◽  
pp. 277-279 ◽  
Author(s):  
Kalyanee Sharma Bhagabati ◽  
Hemen Sarma
Keyword(s):  
Adverse Effect ◽  
Rice Field ◽  
Plant Protection ◽  
Soil Microflora ◽  
High Dose ◽  
Cultivated Rice ◽  
Normal Dose ◽  
Cultivated Soil ◽  
Negative Effect ◽  
Bacteria And Fungi

The present study was carried out to evaluate the effect of indiscriminant use of common pesticides especially insecticide on the population of soil micro flora in cultivated soil of Indian rice field agro-ecosystems. Endosulfan and Dichlorvos @ 1ml/l (normal dose) did not show any adverse effect on soil micro flora; but a high dose 2ml/l showed a negative effect. On the other hand Carbofuran @ 9 kg/acre (normal dose) and 12kg/ acre (high dose) showed an adverse effect on the growth of actinomycetes, bacteria and fungi. The important findings of the present study is that the effect on microbes by applying insecticides reflects the ecological imbalance of microbes in cultivated soil and hamper the microbial equilibrium to some extent. The study focused that the uses of the pesticides as a plant protection agent occasionally hamper the growth of soil micro flora in cultivated rice field.

Cicada-inspired self-cleaning superhydrophobic surfaces

2019 ◽  
Vol 141 (10) ◽  
Author(s):  
Junho Oh ◽  
Sabrina Yin ◽  
Catherine E. Dana ◽  
Sungmin Hong ◽  
Jessica K. Roman ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Air Conditioning ◽  
Microbial Growth ◽  
Heat Transfer Performance ◽  
Self Cleaning ◽  
Bacteria And Fungi ◽  
Wetting Heat ◽  
Droplet Condensation ◽  
Individual Particles ◽  
Living Creature

Abstract Water-based heat transfer surfaces in HVAC&R (Heating, Ventilation, Air Conditioning and Refrigeration) systems have biofouling or microbial growth which might not only impose adverse effects to public health but also deteriorate the heat transfer performance of surfaces. In nature, a living creature is surviving while being exposed to formidable condition such as bacteria and fungi. Cicada wing has known to have multi-functional wings exhibiting nonwetting, and anti-microbial due to nanoscale pillars and biochemicals to achieve non-wetting characteristics. We conducted experiments on cicada wings and cicada-inspired engineered superhydrophobic samples to show that droplets jumping from superhydrophobic wings could carry away individual particles (~100 µm) or cluster of particles. This study was investigated on self-cleaning mechanism using jumping droplet condensation and elucidate further antifouling characteristics of non-wetting heat transfer surfaces.

scholarly journals Pea cultivar Blauwschokker for the phytostimulation of biodiesel degradation in agricultural soil

2019 ◽  
Vol 26 (33) ◽  
pp. 34594-34602 ◽  
Author(s):  
Małgorzata Hawrot-Paw ◽  
Patryk Ratomski ◽  
Małgorzata Mikiciuk ◽  
Jacek Staniewski ◽  
Adam Koniuszy ◽  
...  
Keyword(s):  
Agricultural Soil ◽  
Cost Effective ◽  
Dry Mass ◽  
Soil Microflora ◽  
Physiological Parameters ◽  
Biological Remediation ◽  
Relative Water ◽  
Soil Bacteria And Fungi ◽  
Bacteria And Fungi ◽  
Positive Effect

Abstract Phytoremediation is a cost-effective and ecologically friendly process that involves the use of plants to uptake, accumulate, translocate, stabilize, or degrade pollutants. The present study was conducted to demonstrate the potential of pea (Pisum sativum L. spp. sativum) cultivar Blauwschokker to phytostimulate biodiesel degradation in an agricultural soil, considering the influence of biological remediation on selected physiological parameters of plants and the amount and activity of soil microflora. Biodiesel was spiked into soil in dose of 50 g kg−1 of dry mass soil. The results of the study showed that the rate of biodiesel degradation in the vegetated soil was higher than that occurring by natural attenuation. At the same time, biodiesel showed a positive effect on the growth, development, and activity of soil bacteria and fungi. Moreover, the obtained results showed an improvement in physiological parameters of plants, including an increase in chlorophyll a and total chlorophyll content and higher relative water content in leaves in the presence of biodiesel.

Sign in / Sign up

Export Citation Format

Share Document