Spread of glyphosate‐resistant sourgrass (Digitaria insularis): Independent selections or merely propagule dissemination?          下载免费PDF全文

Hudson K. Takano  Rubem S. de Oliveira Jr.  Jamil Constantin  Claudete A. Mangolim  Maria de F.P.S. Machado  Maycon R.R. Bevilaqua 《Weed Biology and Management》2018,18(1):50-59

The first reports of glyphosate‐resistant (GR) sourgrass (Digitaria insularis) came from Paraguay (2005) and from South and Southeast Brazil, in Paraná (2008), and São Paulo state (2009). The hypothesis of this research is that the evolution of these resistant populations might have occurred independently. To test this hypothesis, a dose–response experiment was conducted in order to confirm resistance and inter simple sequence repeat markers subsequently were evaluated in five sourgrass populations from Paraguay (PY‐R), Paraná (PR‐S and PR‐R), and São Paulo (SP‐S and SP‐R). Resistant populations were confirmed in PY‐R, PR‐R and SP‐R. The resistant populations presented lower polymorphism than susceptible populations, possibly related to the selection pressure exerted by the herbicide. Both similarity matrix and dendrogram provided evidences that the origin of resistance in the populations from Paraguay and Paraná could be the same, which also is explained by their geographical proximity. In contrast, the evolution of GR populations in São Paulo was suggested to occur independently from other locations because resistance evolved in genetically divergent populations. This study’s data provide evidences that GR sourgrass populations from Paraguay and Paraná share a similar genetic background; therefore, it is possible that resistance from Paraguay spread to Paraná through gene flow. The population from São Paulo probably was selected independently because the high values of its genetic structure and low level of gene flow. Independent selections and seed dispersion of GR sourgrass have contributed to the rapid spread of resistance across South America.  相似文献   

A Gaussian multi-component model for the tree diameter distribution in old-growth forests     

Sergiu Andrei Horodnic  Cătălin Constantin Roibu 《European Journal of Forest Research》2018,137(2):185-196

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Removal of Tartrazine from Aqueous Solution by Adsorption on Activated Red Mud     

Ionela-Gabriela Bacioiu  Ligia Stoica  Carolina Constantin  Ana-Maria Stanescu 《Water, air, and soil pollution》2017,228(8):298

In this study, activated red mud was used to develop an effective adsorbent in order to remove a toxic azo dye (tartrazine E102) from aqueous solutions. To increase the adsorption capacity, the red mud was activated by acid-heat treatment using 20 wt.% HCl (RM-HCl). To establish the optimum operating parameters, the influence of pH, adsorbent dose, contact time, initial dye concentration, and stirring rate was investigated. The adsorption equilibrium was studied using Langmuir, Freundlich, Dubinin-Radushkevich, Temkin isotherm models, and the characteristic parameters for each adsorption isotherm were determined. The kinetics of the adsorption process was analyzed by means of pseudo-first-order and pseudo-second-order models. The maximum removal efficiency obtained under optimum conditions was 84.72%. These results were in accordance with the isotherm and kinetic data. The results suggested that tartrazine adsorption process follows the pseudo-second-order kinetic model and also that fits Langmuir isotherm model. The maximum monolayer adsorption capacity was 136.98 mg/g.  相似文献   

Characterization of stage-specific and cross-reactive antigens from Eimeria acervulina by chicken monoclonal antibodies     

Constantinoiu CC  Lillehoj HS  Matsubayashi M  Tani H  Matsuda H  Sasai K  Baba E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(4):403-408

The characterization of five chicken monoclonal antibodies (mAbs) that were developed against apical complex antigens of Eimeria acervulina sporozoites is realized and the mAbs reactivity to merozoites belonging to this species is tested. Using immuno-fluorescence assay (IFA), one mAb (HE-4) that recognized apical antigens common to sporozoites of E. acervulina and E. brunetti bound antigens localized on the apical tip of merozoites from all stages of development examined. The mAb 8E-1, reactive with antigens found on the apical tip of all chicken Eimeria sporozoites, also showed binding to antigens common to merozoites from all generations. Another mAb, 8C-3, which identified an antigen shared by sporozoites apical tip and sporocysts wall of E. acervulina reacted very weak and inconstantly with the merozoites from all generations whereas the mAbs 5D-11 and 8D-2 that recognized antigens shared by the sporozoites of E. acervulina and E. maxima (mAb 5D-11) and E. acervulina and E. brunetti (mAb 8D-2) did not react with the merozoites from any generation. Collectively, these results showed that the invasive stages of chicken Eimeria share cross reactive apical complex antigens which are inter-species and inter-generation-specific that might be components of a potential recombinant vaccine.  相似文献   

Effect of genotype, sex and rearing temperature on carcase and meat quality of guinea fowl   总被引：3，自引：1，他引：2  

Baeza E  Juin H  Rebours G  Constantin P  Marche G  Leterrier C 《British poultry science》2001,42(4):470-476

1. The aim of our study was to analyse the effect of genotype (label and standard), sex and rearing temperature (simulating daily outdoor in the summer or winter) on the carcase and meat quality of guinea fowl. Using 20 animals per treatment, slaughtered at 96 d of age we measured the breast angle and the thickness of the skin on the wing membrane. Carcases were weighed and cut into parts according to a standardised procedure to determine the percentages of abdominal fat, breasts, wings and thighs with shanks. 2. At slaughter, standard guinea fowl were heavier than label guinea fowl and for both genotypes, the females were heavier than the males (+5.6%). The mean value of breast angle was 85 degrees. This value was significantly higher for the standard guinea fowls and for the females of both genotypes compared with males. Thus, female carcases, particularly standard females, were more compact. The skin was thicker for the standard guinea fowls (0.84 mm vs 0.77 mm) which could be due to more subcutaneous fat. 3. Carcase yield was higher for the males (68.7% vs 68.2%). The percentage of abdominal fat was higher for the standard guinea fowls (2.8% vs 2.4%) and for the females of both genotypes compared with males. The label guinea fowls had higher yields of breasts and thighs with shanks. For both lines, the breast and thigh meat of females was judged more tender and less stringy. 4. Low rearing temperature decreased growth performance but had no significant effect on carcase quality.  相似文献   

Bone allografts and adjuvant cisplatin for the treatment of canine appendicular osteosarcoma in 18 dogs     

Morello E  Buracco P  Martano M  Peirone B  Capurro C  Valazza A  Cotto D  Ferracini R  Sora M 《The Journal of small animal practice》2001,42(2):61-66

The results achieved in 18 dogs following the use of frozen bone cortical allografts for limb-sparing resection of non-metastatic canine appendicular osteosarcoma are presented. Three to five cisplatin doses (70 mg/m2) were administered, starting the day after surgery. The mean and median survival times were 478 and 266 days (range 80 to 2,611 days), respectively. The survival rate was 94 per cent at three months, 78 per cent at six months, 35 per cent at 12 months, 23 per cent at 18 months and 19 per cent at 24 months; the disease-free interval was 80 to 1,246 days (mean 365 days, median 266 days). Lung metastasis developed in 55 per cent of the dogs within one year. Complications were observed in 14/18 dogs (78 per cent), comprising local recurrence (28 per cent), allograft infection (39 per cent) and implant failure (11 per cent). Despite complications, limb sparing is a useful alternative to amputation in selected cases of appendicular osteosarcoma.  相似文献   

Photodynamic herbicides VIII. Mandatory requirement of light for the induction of protoporphyrin IX accumulation in acifluorfen-treated cucumber     

Ujjanagouda B. Nandihalli  Rex A. Liebl  Constantin A. Rebeiz 《Pest management science》1991,31(1):9-23

It is shown that continuous illumination is mandatory for the induction of tetrapyrrole accumulation in acifluorfen-sodium-treated plants and for the photosensitization of tetrapyrrole-dependent photodynamic damage. At low concentrations of acifluorfen-sodium (up to 20 μM), photoporphyrin IX appears to be the major light-induced tetrapyrrole that accumulates in the treated plants. At higher concentrations of acifluorfen-sodium, monovinyl chlorophyllide a accumulates in addition to protoporphyrin IX. In the light, the development of photodynamic injury appears to be directly related to the accumulation of the light-induced tetrapyrroles. For example when acifluorfen-sodium-treated plants are returned to darkness, or are treated with tetrapyrrole biosynthesis inhibitors, tetrapyrrole accumulation and photodynamic injury come to a halt. In-vivo and in-organello studies failed, however, to support the commonly held hypothesis that the induction of tetrapyrrole accumulation in the light, in acifluorfen-sodium-treated plants, is only dependent on the inhibition of protoporphyrinogen oxidase. Indeed, when plastids capable of very high rates of tetrapyrrole biosynthesis and accumulation were incubated with δ-aminolevulinic acid and acifluorfen-sodium, either in darkness or in the light, a severe inhibition of protoporphyrin IX and total terapyrrole formation was observed. Althoung these results are compatible with the inhibition of tetrapyrrole formation by acifluorfensodium at the level of protoporphyrinogen oxidase, they indicate that, in addition to that inhibition, other cuellular processes are probably involved in the light-dependent accumulation of protoporphyrin IX in acifluorfensodium-treated plants.  相似文献   

Coherent control of decoherence     

Branderhorst MP  Londero P  Wasylczyk P  Brif C  Kosut RL  Rabitz H  Walmsley IA 《Science (New York, N.Y.)》2008,320(5876):638-643

Manipulation of quantum interference requires that the system under control remains coherent, avoiding (or at least postponing) the phase randomization that can ensue from coupling to an uncontrolled environment. We show that closed-loop coherent control can be used to mitigate the rate of quantum dephasing in a gas-phase ensemble of potassium dimers (K2), which acts as a model system for testing the general concepts of controlling decoherence. Specifically, we adaptively shaped the light pulse used to prepare a vibrational wave packet in electronically excited K2, with the amplitude of quantum beats in the fluorescence signal used as an easily measured surrogate for the purpose of optimizing coherence. The optimal pulse increased the beat amplitude from below the noise level to well above it, and thereby increased the coherence life time as compared with the beats produced by a transform-limited pulse. Closed-loop methods can thus effectively identify states that are robust against dephasing without any previous information about the system-environment interaction.  相似文献   

Evolution of ACCase-inhibitor resistance in Chloris virgata is conferred by a Trp2027Cys mutation in the herbicide target site     

Luiz Augusto Inojosa Ferreira  Rubem Silvério de Oliveira Jr  Jamil Constantin  Caio Brunharo 《Pest management science》2023,79(12):5220-5229

BACKGROUND

Chloris virgata is a troublesome weed in tropical regions. With the evolution of glyphosate resistance in key grass species, acetyl CoA carboxylase (ACCase) inhibitors have become a commonly used tool in soybean production areas in Brazil. We assessed if suspected resistant populations exhibited cross resistance to the different classes of ACCase inhibitors and investigated the resistance mechanisms in C. virgata.

RESULTS

Dose–response experiments revealed resistance to haloxyfop-methyl and pinoxaden, with 432- and 3-fold resistance, respectively, compared to susceptible populations. Due to the lack of genetic resources for C. virgata, we sequenced, assembled, and annotated the genome using short-read Illumina technology. The k-mer analysis estimated a genome size of approximately 336 Mbp, with BUSCO completeness of 97%, and over 36 000 gene models were annotated. We examined if ACCase copy number variation and increased gene expression were involved in the resistance phenotype and found no difference when compared to a susceptible population. A mutation was detected in ACCase that encodes for amino acid position 2027, resulting in a tryptophan-to-cysteine (Trp2027Cys) substitution. We found the resistant population absorbed 11.4% less herbicide and retained 21% more herbicide on the treated leaf compared to the susceptible population. We developed a genotyping assay targeting the resistance-endowing Trp2027Cys substitution for quick resistance diagnosis.

CONCLUSION

A Trp2027Cys amino acid substitution in ACCase confers resistance to haloxyfop and pinoxaden in C. virgata. We provide important insights into the evolutionary history of C. virgata and a draft genome as a useful resource to further our understanding of the biology in the genus Chloris. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

Toumeyella parvicornis versus endotherapic abamectin: three techniques, 1 year after     

Nicolò Di Sora  Luca Rossini  Mario Contarini  Giovanni Mastrandrea  Stefano Speranza 《Pest management science》2023,79(10):3676-3680

Background

Toumeyella parvicornis is an invasive soft scale insect native to North America that is rapidly spreading in Italy and France, provoking severe infestations on Pinus pinea L. To date, the control of this pest is entrusted to three endotherapic techniques whose short-term efficacy is partially known. No information on long-term efficacy is currently available, although fundamental. This work aims to report on the long-term effect that abamectin-based insecticides, injected with the three different techniques, have on adult female populations.

Results

The study was carried out in an infested P. pinea forest in the area of Rome, Italy. Results showed that the tested methods had a similar long-term effect, and only in one case there were differences with the untreated control. Multiresidue analysis reported a zero level of abamectin in plant tissues 14 months apart from injection, except for one treatment where pesticide concentration was just above the limit of quantification.

Conclusions

This study represents the first long-term evaluation about endotherapic control strategy against T. parvicornis. In fact, the pest may quickly bring the death and fall of the stone pines, representing a concerning risk for citizens, however, control actions to manage it are still partially known and deserve more in-depth investigations. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献