HIGH-DOSAGE TREATMENT OF A QUEBEC STREAM WITH BACILLUS THURINGIENSIS SEROVAR. ISRAELENSIS: EFFICACY AGAINST BLACK FLY LARVAE (DIPTERA: SIMULIIDAE) AND IMPACT ON NON-TARGET INSECTS

AbstractA typical lake outlet of the Canadian Shield was treated for 15 min with a high dose (5.28 g/L s−1 of discharge) of Teknar®, a commercial formulation of Bacillus thuringiensis serovar. israelensis. Efficacy on Simuliidae larvae and impact on non-target aquatic insects of this stream were monitored using drift nets, counting plates, and artificial turf substrates along a 1000-m section downstream of the site of application. Compared with a 4-day pre-treatment average for 12-h sampling periods, drift of Simuliidae increased from 64 to 92 ×, with shorter peaks of 133–184 ×, 2–6 h after treatment. There was no evident drift increase in larvae of Ephemeroptera, Plecoptera, Trichoptera, Chironomidae, or dipterous pupae, but larvae of Blephariceridae (Diptera) were severely affected as their drift was increased by up to 50 × and remained high for 3 days. After 30 h the mortality of Simuliidae on counting plates ranged from 95 to 82% in the first 300 m, with detachment rates of 78.5–46.5%. Densities of non-target insect larvae were not reduced on the artificial substrates, except for 2 genera of Chironomidae (Eukiefferella and Polypedilum) which were reduced 26 to 39% of their original density. Drifting larvae of 1 chironomid genus (Phaenopsectra) also showed symptoms of toxemia by B.t.i. The main impact of the treatment was thus seen in 2 Nematocera families (Chironomidae and Blephariceridae) which were mainly exposed to B.t.i. sedimented on the bottom of the stream or attached to periphyton growing on rocks.

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Patterns of dispersion of aquatic insects colonizing artificial substrates in a southern Ontario stream

Canadian Journal of Zoology ◽

10.1139/z95-053 ◽

1995 ◽

Vol 73 (3) ◽

pp. 458-468 ◽

Cited By ~ 4

Author(s):

Jane E. Rutherford

Keyword(s):

Aquatic Insects ◽

Narrow Band ◽

Artificial Substrates ◽

Artificial Turf ◽

Stream Invertebrates ◽

Southern Ontario ◽

Competition For Space

Modified artificial turf substrates were readily colonized by stream invertebrates, supporting 20 or more taxa after 10 or 22 days in the stream. Of the individuals present, 50–80% belonged to four taxa: Hydropsychidae, Hydroptila sp. (larvae and pupae), Rheotanytarsus sp., and Baetidae. All four taxa displayed significantly aggregated patterns of dispersion (as shown by Clark–Evans–Donnelly indices) on most of the 6 substrates. The hydropsychids and the Hydroptila sp. pupae appeared to have the highest degree of aggregation, especially at high densities; both taxa occupied about the same areas on the substrates, forming discrete bands of occupation at the upstream and downstream edges as well as along a narrow band near the middle of the substrates. Weakly positive (but generally nonsignificant) Φ2 values (intertaxon association indices based on presence–absence data) coupled with negative Iai values (intertaxon association indices based on joint abundances) for the Hydropsychidae – Rheotanytarsus sp. and Hydroptila sp. – Rheotanytarsus sp. pairings indicate that Rheotanytarsus sp. occupies quite different areas of the substrates than either the hydropsychids or Hydroptila sp. pupae, suggesting that competition for space may be important amongst these sessile taxa.

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Isolation of an Anti-fatigue Preparation from Cellulase-treated Maca by Hydroalcoholic Extraction

Current Topics in Nutraceutical Research ◽

10.37290/ctnr2641-452x.17:93-98 ◽

2017 ◽

Vol 17 (1) ◽

pp. 93-98

Author(s):

Zheng Yue ◽

Zhang Wen-Cheng ◽

Wu Ze-Yu ◽

Fu Chuan-Xiang ◽

Gao Han ◽

...

Keyword(s):

Positive Control ◽

Glycogen Storage ◽

Hepatic Glycogen ◽

Time To Exhaustion ◽

High Dose ◽

Hydroalcoholic Extract ◽

Swimming Time ◽

Significant Difference ◽

Pre Treatment ◽

Better Than

The purpose of this study was to evaluate the anti-fatigue activity of maca hydroalcoholic extract (ME), which mainly contains macamides and polysaccharides. ME was prepared by circumfluence extraction with enzymatic pre-treatment. Anti-fatigue activity of ME was investigated in weight-loaded forced swimming mice, with pure macamides and commercially available maca tablet as positive control. Compared with normal group, pure macamides treatment group could prolong the swimming time to exhaustion, but there was no statistically significant difference (P > 0.05); while ME (middle-dose and high-dose groups) could effectively prolong the swimming durations (P < 0.05). Supplementation with pure macamides significantly decreased blood lactic acid (BLA), whereas ME significantly increased hepatic glycogen (HG), decreased BLA, and blood urea nitrogen (BUN) compared with those in normal control (P < 0.05). The results suggested that the anti-fatigue effect of ME was better than that of pure macamides, which can be explained by the increase of glycogen storage and the reduction of metabolites accumulation.

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Regulation of the Packaging of Bacillus thuringiensis δ-Endotoxins into Inclusions

Applied and Environmental Microbiology ◽

10.1128/aem.67.11.5032-5036.2001 ◽

2001 ◽

Vol 67 (11) ◽

pp. 5032-5036 ◽

Cited By ~ 15

Author(s):

Lily Chang ◽

Rian Grant ◽

Arthur Aronson

Keyword(s):

Bacillus Thuringiensis ◽

Consensus Sequence ◽

Luria Bertani ◽

Insect Larvae ◽

Inclusion Formation ◽

Reducing Conditions ◽

Mrna Ratio ◽

Yeast Extract Medium ◽

Relative Deficiency ◽

Binding Sequence

ABSTRACT During sporulation, many Bacillus thuringiensis subspecies synthesize several related δ-endotoxins which are packaged into bipyramidal intracellular inclusions. These inclusions are solubilized in the alkaline, reducing conditions of the midguts of susceptible insect larvae and are converted by proteolysis to active toxins. The toxins insert into the membranes of cells lining the midgut and form cation-selective channels, which results in lethality. There are three δ-endotoxins, Cry1Ab3, Cry1Ca1, and Cry1Da1, present in the inclusions produced by a B. thuringiensis subsp.aizawai cell. While the ratio of the steady-state mRNAs for these three protoxins has been shown to differ (cry1Ab3/cry1Ca1/cry1Da1 mRNA ratio, 4:2:1), the half-lives of the cry1Da1 and cry1Ab3 mRNAs were found to be similar, indicating that there were differences in the transcription rates. The relative contents of these δ-endotoxins in purified inclusions from B. thuringiensissubsp. aizawai have been measured previously, and an even greater relative deficiency of the Cry1Da1 protoxin (ratio, 20:12:1) was found. In order to account for this deficiency, other steps which could be involved in inclusion formation, such as translation and packaging, were examined. The three cry genes have the same dual overlapping promoters, but the ribosome binding sequence for the cry1Da1 gene was not the consensus sequence. Translation was enhanced about fourfold by changing to the consensus sequence. In addition, the relative amount of Cry1Da1 protoxin in inclusions was twofold lower when cells were sporulated in Luria-Bertani (LB) medium than when cells were sporulated in a glucose-yeast extract medium. This difference was attributable to packaging since the relative amounts of Cry1Da1 antigen in cells sporulating in the two media were the same. Some factor(s) required for packaging of the Cry1Da1 protoxin in inclusions is apparently limiting in LB medium. Differences in the initial transcription rates, translation efficiencies, and packaging all contribute to the δ-endotoxin composition of an inclusion.

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Long-term clinical experience of high-dose ablative lung radiotherapy: High pre-treatment [18F]Fluorodeoxyglucose-positron emission tomography maximal standardized uptake value of the primary tumor adversely affects treatment outcome

Lung Cancer ◽

10.1016/j.lungcan.2012.12.023 ◽

2013 ◽

Vol 80 (2) ◽

pp. 172-178 ◽

Cited By ~ 16

Author(s):

Dong Soo Lee ◽

Yeon Sil Kim ◽

Ie Ryung Yoo ◽

Young Nam Kang ◽

Seoung Jun Kim ◽

...

Keyword(s):

Standardized Uptake Value ◽

Emission Tomography ◽

High Dose ◽

Fluorodeoxyglucose Positron Emission Tomography ◽

Positron Emission ◽

Pre Treatment ◽

Maximal Standardized Uptake Value ◽

Lung Radiotherapy ◽

Fluorodeoxyglucose Positron Emission

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Technology of production of biopesticides based on Bacillus thuringiensis

FOOD RESOURCES ◽

10.31073/foodresources2021-16-03 ◽

2021 ◽

Vol 9 (16) ◽

pp. 28-38

Author(s):

Anatolii Bezusov ◽

◽

Valentyna Krutiakova ◽

Olena Myroshnichenko ◽

Nataliia Dotsenko ◽

...

Keyword(s):

Bacillus Thuringiensis ◽

Corn Oil ◽

Raw Materials ◽

Culture Fluid ◽

Scientific Work ◽

Insect Larvae ◽

Effective Prevention ◽

Research Results ◽

Wide Range ◽

Vegetable Raw Materials

Subject of research. Biopesticides are based on live cultures of specially selected beneficial microorganisms with controlled properties. They have a pronounced phytoprotective and stimulating effect, thus providing effective prevention and protection of plants from diseases. The obtained biological product increases productivity, improves the quality and structure of the crop, does not accumulate in plants, which allows to obtain environmentally friendly agricultural products and does not harm the environment. Among the large number of bacteria, as a source of microbiological insecticide is Bacillus thuringiensis, which infects lepidopteran pests and leads to their death. Preparations based on this strain are effective when used in low concentrations of solutions. The Bacillus thuringiensis strain produces several toxins with insecticidal action, including β-exotoxin and δ-endotoxin. Toxic effect is manifested and leads to paralysis of the intestinal tract of parasites. Preparations β-exotoxin and δ-endotoxin are obtained by culturing Bacillus thuringiensis bacteria in a liquid medium. The scientific work proposes a method of industrial production using by-products of vegetable raw materials, which makes it economically feasible to use such substrates. The purpose of the study is the development of technology, formulation of nutrient medium, process parameters for the cultivation of bacteria of the genus Bacillus thuringiensis and obtaining a culture fluid containing substances of the class of biopesticides. Methods. Standard and generally accepted methods of research of bioproducts in biotechnology. The formation of bioinsecticides was established by hydrolysis methods, followed by determination of the component of β-exotoxin – ribose, the formation of octagonal crystals of exotoxin – by microscopic method. Research results. Three variants of nutrient media, which include yeast-polysaccharide complex: corn flour, corn oil, yeast autolysate were developed. The parameters of the bacterial cultivation process were studied. The final product is a paste or powder with a titer of 35 .109 spores in 1 g of the bioproduct. Scope of research results. Microbiological preparations based on Bacillus thuringiensis are highly specific and act only on insect larvae from the classes Lepidoptera and Diptera. The resulting biopesticide can be used against pests of a wide range of vegetable and fruit crops.

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In vitro infection experiments with eggs of the nematode Contracaecum rudolphii Hartwich, 1964 (sensu lato) targeting aquatic insect larvae (Odonata: Coenagrionidae and Libellulidae; Trichoptera: Integripalpia) as possible intermediate hosts

Oceanological and Hydrobiological Studies ◽

10.2478/s13545-014-0129-8 ◽

2014 ◽

Vol 43 (2) ◽

Author(s):

Janina Dziekońska-Rynko ◽

Jerzy Rokicki ◽

Katarzyna Mierzejewska

Keyword(s):

Aquatic Insects ◽

Aquatic Insect ◽

Intermediate Hosts ◽

Insect Larvae ◽

Contracaecum Rudolphii ◽

High Prevalence ◽

Nematode Eggs ◽

Newly Hatched Larvae ◽

Aquatic Insect Larvae

AbstractThe availability of aquatic insects (Odonata: Coenagrionidae, Libellulidae and Trichoptera: Integripalpia) as potential intermediate hosts for the nematode Contracaecum rudolphii Hartwich, 1964 sensu lato was studied under laboratory conditions. The infective material consisted of nematode eggs, newly hatched larvae, as well as in vitro infected cyclopoid copepods. High prevalence and intensity of infection associated with a low mortality of aquatic insect larvae suggests that they may serve as intermediate hosts for C. rudolphii and constitute a major reservoir of C. rudolphii larvae in aquatic habitats.

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Control of chironomid midge larvae in wastewater stabilisation ponds: comparison of five compounds

Water Science & Technology ◽

10.2166/wst.2005.0460 ◽

2005 ◽

Vol 51 (12) ◽

pp. 191-199 ◽

Cited By ~ 6

Author(s):

R. Craggs ◽

L. Golding ◽

S. Clearwater ◽

L. Susarla ◽

W. Donovan

Keyword(s):

New Zealand ◽

Bacillus Thuringiensis ◽

Urban Areas ◽

Large Scale ◽

Adult Emergence ◽

Small Scale ◽

Slight Reduction ◽

Organic Loading ◽

Valuable Component ◽

Pre Treatment

Chironomid midge larvae are a valuable component of wastewater stabilisation pond (WSP) ecology. However, in high numbers, adult midge swarms can be a nuisance to near-by urban areas. Improving WSP treatment by incorporating aerobic or maturation ponds or by the addition of pre-treatment to reduce organic loading also increases the availability of aerobic sediment (midge larva habitat) in the pond system and the potential for midge nuisance problems. The efficacy of Maldison, an organophosphate traditionally used to control midge larvae in New Zealand WSPs, was compared to Bacillus thuringiensis var. israelensis (Bti), Methoprene, Pyriproxyfen and Diflubenzuron which are all more specific to insects and have fewer adverse environmental effects. Initial laboratory trials established the concentration of each compound required to achieve 95% control of the midge population. During 21-day small-scale trials within the WSP, Bti, Diflubenzuron and Maldison reduced live larvae numbers substantially (80–89%) compared to controls and adult midge emergence was markedly reduced by all compounds (72–96%). Large-scale trials with Bti (Vectobac® WG) powder (1000 μg/L) only caused a slight reduction in midge larvae numbers compared to controls and had little effect on adult emergence, however, Methoprene (Prolink XRG granules) (50 μgAI/L) reduced midge adult emergence by ∼80% over 25 days and has been used successfully to control several midge nuisance outbreaks.

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