scholarly journals The Biology and Ecology of the Diamondback Moth, Plutella xylostella (L.) in Eastern Ontario Revisited

2018 ◽  
Author(s):  
Tina Dancau

Diamondback moth, Plutella xylostella Linnaeus (Lepidoptera: Plutellidae) is a globally distributed pest on brassicaceous crops. This study aimed to follow up with aspects of earlier research, mainly to revisit the potential for overwintering of diamondback moth in the Ottawa area, to investigate present day population dynamics using a life-table approach and to use next generation sequencing to describe the diamondback moth microbiome. A review of the literature has reaffirmed that diamondback moth may not be capable of overwintering in Ottawa with populations likely migrant-driven. The population dynamics and parasitoid community appear to be unaltered after 65 years. The microbiome of diamondback moth larvae was dominated by Enterococcaceae, a family of bacteria hypothesized to aid in resistance and detoxification. This can provide opportunities for the introduction of new biological control agents and tools for diamondback moth management in the future.

2019 ◽  
Vol 72 ◽  
pp. 253-259 ◽  
Author(s):  
Michal Kuchár ◽  
Travis R. Glare ◽  
John G. Hampton ◽  
Ian A. Dickie ◽  
Mary C. Christey

Plutella xylostella (diamondback moth) is a prominent pest of brassicas which is now resistant to most insecticides. Despite years of research, the range of available products used in biological control of diamondback moth is still somewhat limited. We isolated putative endophytic fungi from New Zealand cabbage plants to search for unique biological control agents of diamondback moth larvae. The larvae were fed leaf discs from commercially grown cabbage covered in spores from endophytic fungal isolates to test the insecticidal properties of these fungi. Twenty of the 52 fungal isolates tested failed to kill any diamondback moth larvae. However, three isolates of Lecanicillium muscarium induced mortality greater than 80%. While these isolates have potential for use in biological control applications, further research into propagation, formulation, and method, rate and timing of application is needed.


1969 ◽  
Vol 87 (1-2) ◽  
pp. 31-49
Author(s):  
Ángel L. González-Rodríguez ◽  
Raúl Macchiavelli

A field study (1998-99) was conducted at the Juana Díaz Substation (AESUPR) to determine the population dynamics of Plutella xylostella (L.) in cabbage in a monoculture and in relay-type substitutive dicultures of cabbage/tomato or cabbage/wedelia. In 1998, subplots were created by spraying half of the main plots with Bacillus thuringiensis (Bt)-based products. All treatments, except for the control monoculture, were sprayed with Bt-based products in 1999. Cotesia plutellae Kurjumov, a larval parasitoid of P. xylostella, was released augmentatively for biological control. Tomato, as a companion crop, showed a tendency for reducing P. xylostella densities in cabbage, reduced the levels of C. plutellae parasitism and competed with cabbage, causing fewer and smaller heads. Bt-based sprays reduced P. xylostella densities, but these were at damaging levels at the critical stages of cupping and head formation, thus permitting cosmetic damage to cabbage heads. Cotesia plutellae did not regulate the P. xylostella population, thus resulting in parasitism levels of 65.3 and 11.6% in the unsprayed monoculture in 1998 and 1999, respectively. The legume Crotalaria juncea L. as a border did not improve parasitism by C. plutellae. The interpretation and application of the results are discussed. 


2017 ◽  
Vol 45 (1) ◽  
pp. 280-286 ◽  
Author(s):  
Hoang Chinh NGUYEN ◽  
Thi Van Anh TRAN ◽  
Quoc Linh NGUYEN ◽  
Nhu Nhut NGUYEN ◽  
Minh Khiem NGUYEN ◽  
...  

Biocontrol offers an attractive alternative to the use of chemical pesticides in agricultural pest management. The development of high levels of resistance to chemical pesticides have forced researchers to find more alternative biological control agents. The aims of this study were to isolate Paecilomyces spp. with high virulence against diamondback moth (Plutella xylostella) and Oriental leafworm moth (Spodoptera litura), and to investigate suitable agro-industrial residues as a substrate used for solid state fermentation for sporulation of isolates. In this study, Paecilomyces spp. were isolated from soil and insects and identified by morphological and sequencing analyses. The pathogenicity of these isolates was evaluated on Pl. xylostella and S. litura to identify strains with the highest virulence. In addition, agro-industrial residues were used as a cheap substrate for investigating a suitable medium for sporulation on an industrial scale. Six strains of Paecilomyces spp. were isolated including one strain of P. lilacinus and five strain of P. javanicus. P. lilacinus PL01 showed the highest virulence against both Pl. xylostella and S. litura with respective LT50 values of 2.51 and 7.09 days. The five isolated P. javanicus strains also strongly infected Pl. xylostella with LT50 values of 2.52~6.59 days. For sporulation, brown rice alone or brown rice mixed with rice husks and wheat bran or rice bran was suitable for cultivating these isolates. Two newly isolated species of Paecilomyces, P. lilacinus and P. javanicus, can be used as biological control agents for controlling Pl. xylostella and S. litura.


2021 ◽  
Vol 14 (1) ◽  
pp. 3-8
Author(s):  
Philip W. Tipping ◽  
Melissa R. Martin ◽  
Jeremiah R. Foley ◽  
Ryan M. Pierce ◽  
Lyn A. Gettys

AbstractThe potential of Melaleuca quinquenervia (Cav.) S.T. Blake to reinvade cleared areas was evaluated over a 13-yr period that included two wildfires and the introduction of biological control agents. The first wildfire occurred in 1998 and was followed by a mean of 591.5 recruited seedlings m−2. Recruits from that fire were cleared 7 yr later in July 2005 for a second experiment to evaluate seedling recruitment into cleared areas. Seed rain, seedling recruitment and mortality, and sapling growth rates were measured in four plots located around individual large reproductive trees. A second natural wildfire in 2007 burned through those plots, leading to increases in seed rain followed by a pulse in recruitment of 21.04 seedlings m−2, 96.5% fewer than after the 1998 fire. Recruits in half of the plots around each tree were then treated with regular applications of an insecticide to restrict herbivory by biological control agents, while herbivory was not restricted in the other half. There was no difference in seedling mortality between treatments 1,083 d post-fire (2007) with 96.6% seedling mortality in the unrestricted herbivory treatment and 89.4% mortality in the restricted herbivory treatment. Recruits subjected to the restricted herbivory treatment grew taller than those in the unrestricted herbivory treatment, 101.3 cm versus 37.4 cm. Many of the recruits were attacked by the biological control agents, which slowed their growth. Although solitary M. quinquenervia trees retain some capacity to reinvade areas under specific circumstances, there was a downward trend in their overall invasiveness at this site, with progressively smaller recruitment cohorts due to biological control agents. Land managers should prioritize removing large reproductive trees over treating recently recruited populations, which can be left for many years for the biological control agents to suppress before any additional treatment would be needed.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4359-4359
Author(s):  
Koji Sasaki ◽  
Rashmi Kanagal-Shamanna ◽  
Guillermo Montalban-Bravo ◽  
Rita Assi ◽  
Kiran Naqvi ◽  
...  

Abstract Introduction: Clearance of detected somatic mutations at complete response by next-generation sequencing is a prognostic marker for survival in patients with acute myeloid leukemia (AML). However, the impact of allelic burden and persistence of clonal hematopoiesis of indeterminate potential (CHIP)-associated mutations on survival remains unclear. The aim of this study is to evaluate the prognostic impact of allelic burden of CHIP mutations at diagnosis, and their persistence within 6 months of therapy. Methods: From February 1, 2012 to May 26, 2016, we reviewed 562 patients with newly diagnosed AML. Next-generation sequencing was performed on the bone marrow samples to detect the presence of CHIP-associated mutations defined as DNMT3A, TET2, ASXL1, JAK2 and TP53. Overall survival (OS) was defined as time period from the diagnosis of AML to the date of last follow-up or death. Univariate (UVA) and multivariate Cox proportional hazard regression (MVA) were performed to identify prognostic factors for OS with p value cutoff of 0.020 for the selection of variables for MVA. Landmark analysis at 6 months was performed for the evaluation of the impact of clearance of CHIP, FLT3-ITD, FLT3D835, and NPM1 mutations. Results: We identified 378 patients (74%) with AML with CHIP mutations; 134 patients (26%) with AML without CHIP mutations. The overall median follow-up of 23 months (range, 0.1-49.0). The median age at diagnosis was 70 years (range, 17-92) and 66 years (range, 20-87) in CHIP AML and non-CHIP AML, respectively (p =0.001). Of 371 patients and 127 patients evaluable for cytogenetic in CHIP AML and non-CHIP AML, 124 (33%) and 25 patients (20%) had complex karyotype, respectively (p= 0.004). Of 378 patients with CHIP AML, 183 patients (48%) had TET2 mutations; 113 (30%), TP53; 110 (29%), ASXL1; 109 (29%), DNMT3A; JAK2, 46 (12%). Of 378 patients, single CHIP mutations was observed in 225 patients (60%); double, 33 (9%); triple, 28 (7%); quadruple, 1 (0%). Concurrent FLT3-ITD mutations was detected in 47 patients (13%) and 12 patients (9%) in CHIP AML and non-CHIP AML, respectively (p= 0.287); FLT3-D835, 22 (6%) and 8 (6%), respectively (p= 0.932); NPM1 mutations, 62 (17%) and 13 (10%), respectively (p= 0.057). Of 183 patients with TET2-mutated AML, the median TET2 variant allele frequency (VAF) was 42.9% (range, 2.26-95.32); of 113 with TP53-mutated AML, the median TP53 VAF, 45.9% (range, 1.15-93.74); of 109 with ASXL1-mutated AML, the median ASXL1 VAF was 34.5% (range, 1.17-58.62); of 109 with DNMT3A-mutated AML, the median DNMT3A VAF was 41.8% (range, 1.02-91.66); of 46 with JAK2-mutated AML, the median JAK2 VAF was 54.4% (range, 1.49-98.52). Overall, the median OS was 12 months and 11 months in CHIP AML and non-CHIP AML, respectively (p= 0.564); 16 months and 5 months in TET2-mutated AML and non-TET2-mutated AML, respectively (p <0.001); 4 months and 13 months in TP53-mutated and non-TP53-mutated AML, respectively (p< 0.001); 17 months and 11 months in DNMT3A-mutated and non-DNMT3A-mutated AML, respectively (p= 0.072); 16 months and 11 months in ASXL1-mutated AML and non-ASXL1-mutated AML, respectively (p= 0.067); 11 months and 12 months in JAK2-murated and non-JAK2-mutated AML, respectively (p= 0.123). The presence and number of CHIP mutations were not a prognostic factor for OS by univariate analysis (p=0.565; hazard ratio [HR], 0.929; 95% confidence interval [CI], 0.722-1.194: p= 0.408; hazard ratio, 1.058; 95% confidence interval, 0.926-1.208, respectively). MVA Cox regression identified age (p< 0.001; HR, 1.036; 95% CI, 1.024-1.048), TP53 VAF (p= 0.007; HR, 1.009; 95% CI, 1.002-1.016), NPM1 VAF (p=0.006; HR, 0.980; 95% CI, 0.967-0.994), and complex karyotype (p<0.001; HR, 1.869; 95% CI, 1.332-2.622) as independent prognostic factors for OS. Of 33 patients with CHIP AML who were evaluated for the clearance of VAF by next generation sequencing , landmark analysis at 6 months showed median OS of not reached and 20.3 months in patients with and without CHIP-mutation clearance, respectively (p=0.310). Conclusion: The VAF of TP53 and NPM1 mutations by next generation sequencing can further stratify patients with newly diagnosed AML. Approximately, each increment of TP53 and NPM1 VAF by 1% is independently associated with 1% higher risk of death, and 2% lower risk of death, respectively. The presence of CHIP mutations except TP53 does not affect outcome. Disclosures Sasaki: Otsuka Pharmaceutical: Honoraria. Short:Takeda Oncology: Consultancy. Ravandi:Macrogenix: Honoraria, Research Funding; Seattle Genetics: Research Funding; Sunesis: Honoraria; Xencor: Research Funding; Jazz: Honoraria; Seattle Genetics: Research Funding; Abbvie: Research Funding; Macrogenix: Honoraria, Research Funding; Bristol-Myers Squibb: Research Funding; Orsenix: Honoraria; Abbvie: Research Funding; Jazz: Honoraria; Xencor: Research Funding; Orsenix: Honoraria; Sunesis: Honoraria; Amgen: Honoraria, Research Funding, Speakers Bureau; Bristol-Myers Squibb: Research Funding; Astellas Pharmaceuticals: Consultancy, Honoraria; Amgen: Honoraria, Research Funding, Speakers Bureau; Astellas Pharmaceuticals: Consultancy, Honoraria. Kadia:BMS: Research Funding; Abbvie: Consultancy; Takeda: Consultancy; Jazz: Consultancy, Research Funding; Takeda: Consultancy; Amgen: Consultancy, Research Funding; Celgene: Research Funding; Novartis: Consultancy; Amgen: Consultancy, Research Funding; BMS: Research Funding; Jazz: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Novartis: Consultancy; Abbvie: Consultancy; Celgene: Research Funding. DiNardo:Karyopharm: Honoraria; Agios: Consultancy; Celgene: Honoraria; Medimmune: Honoraria; Bayer: Honoraria; Abbvie: Honoraria. Cortes:Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Daiichi Sankyo: Consultancy, Research Funding; Astellas Pharma: Consultancy, Research Funding; Arog: Research Funding.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 520-520
Author(s):  
Laurence Lodé ◽  
Audrey Ménard ◽  
Marion Loirat ◽  
Maxime Halliez ◽  
Steven Richebourg ◽  
...  

Abstract Landscape analyses of mutational patterns have shown that virtually all myelodysplastic syndromes (MDS) harbor somatic mutations in >80% of cases. These molecular alterations provide useful clonality markers with a potential for early diagnosis of MDS when only cytopenia without marked dysplasia is observed. These markers have been proposed as future prognostic tools to guide therapeutic strategies (Bejar et al., 2011; Itzykson et al, 2013; Mufti et al 2013). Mutational analysis is finally a good way to track disease complexity by deciphering oligoclonality in MDS and better understand clonal evolution. Alterations in the TP53 gene are the most common cause of tumor escape from apoptosis. The aim of this study was to identify TP53 mutations in consecutive samples of lower-risk MDS (IPSS ≤1) with del(5q)obtained at follow-up or progression after sequential classical treatments. Next-generation sequencing (NGS) was used to backtrack the mutant clone(s) identified in late samples. The study was performed both by conventional Sanger sequencing and NGS on a GS Junior Instrument (Roche Applied Science, Mannheim, Germany). For each sample, eight exons (4-11) were amplified from 320 ng of DNA with preconfigured primer plates provided within the IRON II study network. PCR reactions were performed using the FastStart High Fidelity PCR System kit (Roche Applied Science). After double purification with Agencourt AMPure XP beads (Beckman Coulter, Miami, FL), exon-specific amplicon pools were generated and quantified using the Quant-iT™ Broad-Range PicoGreen DNA Assay Kit (Invitrogen, Carlsbad, CA). Emulsion PCR was performed with GS Junior emPCR Reagents (Lib-A) (Roche Applied Science) using 5 x 106 beads at a copy per bead ratio of 0.6. Finally, a fraction of 5-7% enriched beads was loaded on GS Junior Titanium sequencing PicoTiterPlate kit (Roche Applied Science). Data were analyzed for sequence alignment and variant detection using the GS Junior Sequencer and GS Amplicon Variant Analyzer softwares, versions 2.7 and 2.9 (Roche Applied Science). The results were further processed using the Sequence Pilot software version 4.0.1 (JSI Medical Systems, Kippenheim, Germany). The sensitivity of variant detection was set to a lower limit of >1% for bidirectional reads. This threshold was chosen according to a recent study investigating the assay's lower limit of detection (Grossmann et al., 2013), thus underlining the strength of NGS to identify subclones at a low frequency, not detectable by conventional Sanger analysis. A total of 89 DNA samples were extracted from the cytogenetics pellets of a cohort of 40 MDS with del(5q). TP53 mutation analysis was performed on 40 initial and 49 follow-up or progression samples including serial samples for 23 subjects. The depth of coverage was at least 500X and up to 8,444X per amplicon. Of those samples obtained and analysed at time of last follow-up or progression, 14 (61%) had TP53 mutations, mostly in the DNA-binding domain. Performing backtracking on previously collected serial samples, TP53 mutations were retrieved by NGS in 43% of initial samples (n=6), which is different from what was previously described by Jädersten et al (2011). A complete scenario of clonal evolution was retrieved in 11 cases, evidenced by TP53 mutations and/or cytogenetics. These were always consecutive to treatment with lenalidomide, yet 6 of the 12 cases without clonal evolution were also consecutive lenalidomide. Figure 1 provides the example of a complete follow-up including nine time points. More correlation with treatment will be provided. Although lenalidomide remains the treatment of choice for MDS with del(5q), resistant subclones may survive and culminate even following therapy initiation. This theory was recently suggested by Landau et al. in CLL (2013) and our test results support this. Early detection of emerging subclones could lead to initiation of alternative treatment, and we thus propose that a monitoring of TP53 alleles is performed annually after the onset of therapy for MDS using NGS. Figure 1. Figure 1. Disclosures: Kohlmann: MLL Munich Leukemia Laboratory: Employment. Moreau:CELGENE: Honoraria, Speakers Bureau; JANSSEN: Honoraria, Speakers Bureau.


2003 ◽  
Vol 38 (1) ◽  
pp. 59-71 ◽  
Author(s):  
Travis A. Hill ◽  
Rick E. Foster

The effects of insecticides on the diamondback moth, Plutella xylostella (L)., and its parasitoid, Diadegma insulare (Cresson), were evaluated in the field. Insecticides applied for control of the diamondback moth caused variations in parasitism by D. insulare ranging from 20 to 84%. Permethrin applications were effective at controlling diamondback moth. Applications of spinosad also resulted in low diamondback moth populations; however, percent parasitism was higher than in untreated plots and over 4× higher than in plots treated with permethrin. Selective materials that conserve D. insulare populations and maintain diamondback moth populations below economic thresholds may reduce the frequency of application, thus prolonging the efficacy of these materials.


2018 ◽  
Vol 52 ◽  
pp. 48-55 ◽  
Author(s):  
Andraz Smon ◽  
Barbka Repic Lampret ◽  
Urh Groselj ◽  
Mojca Zerjav Tansek ◽  
Jernej Kovac ◽  
...  

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 4641-4641
Author(s):  
Lan Zhang ◽  
Xingnong Ye ◽  
Shengjie Wang ◽  
Keyi Jin ◽  
Shuna Luo ◽  
...  

Abstract Myeloproliferative neoplasms (MPNs) include three classical subtypes: polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Since prefibrotic primary myelofibrosis (pre-PMF) was recognized as a separate entity in the 2016 revised classification of MPN, it has been a subject of debate among experts due to its indefinite diagnosis. However, pre-PMF usually has a distinct outcome compared with either ET or overt PMF. We conducted a retrospective study of MPN patients from October 2014 to June 2020 in the Fourth Affiliated Hospital of Zhejiang University. Patients who were diagnosed with ET, pre-PMF or overt-MF according to the 2016 WHO Classification were included. We reviewed the clinical parameters, haematologic information, and genetic mutations of patients using next-generation sequencing (NGS). Mutation screening was performed in 44 patients by next-generation sequencing techniques, 84 genes and 258 mutations were detected. JAK2 was the most frequently mutated gene (25/44, 56.82%), followed by TET2 (14/44, 31.82%), KMT2C (13/44, 29.55%), and ASXL1 (10/44, 23.73%) in MPN (Figure 1-A). The VAFs of all studied genes with mutation frequencies &gt;10% are shown in Figure 1-B. Of the 20 patients with ET, 9 (45%) were positive for the JAK2 mutation, 5 (25%) carried FAT1, 5 (25%) carried KMT2C, and 4 (20%) carried CALR. Of the 5 patients with pre-PMF, 4 (80%) carried JAK2, 3 (60%) carried EP300, and 2 (40%) carried TET2. Of the 19 patients with overt PMF, 12 (63%) carried JAK2, 10 (53%) carried TET2, 7 (37%) carried ASXL1, and 6 (32%) carried KMT2C, as reported in Figure 2. The median follow-up was 36 months for ET, 42 months for pre-PMF, and 53 months for overt PMF. Overall survival between pre-PMF, overt PMF, and ET was significantly different (P&lt;0.001), as shown in Figure 3. During the follow-up time, only one death of ET was registered, so we analysed the impact of clinical parameters and mutational status at diagnosis on outcome in PMF, including pre-PMF and overt PMF. We performed Kaplan-Meier curves to examine the relationships between the clinical parameters and patient survival. We found that male sex (P=0.0107), MPN10 symptoms (P=0.0354), anaemia (haemoglobin&lt;120g/L, P=0.0239), and thrombocytopenia (platelet count &lt;100 ×10 9/L, P=0.0002) were significantly related to inferior OS (Figure 4). Pre-PMF patients exhibited higher leukocyte counts, higher LDH values, a higher frequency of splenomegaly, and a higher incidence of hypertension than ET patients. On the other hand, pre-PMF patients had higher platelet counts and haemoglobin levels than overt PMF patients. Molecular analysis revealed that the frequency of EP300 mutations was significantly increased in pre-PMF patients compared with ET and overt PMF patients. In terms of outcome, male sex, along with symptoms including MPN10, anaemia, thrombocytopenia, and KMT2A and CUX1 mutations, indicated a poor prognosis for PMF patients. In conclusion, we identified differences in the clinical, haematologic, and molecular presentations of ET, pre-PMF, and overt PMF patients, indicating that comprehensive evaluation of not only BM features but also clinical, haematologic, and molecular profiles is needed for accurate diagnosis and treatment of these three disease entities. The molecular analysis revealed that pre-PMF might be relevant to EP300 mutation, demonstrating the value of molecular examination. The results of this study indicated that comprehensive evaluation of BM features, clinical phenotypes, haematologic parameters, and molecular profiles is needed for the accurate diagnosis and treatment of ET, pre-PMF, and overt PMF patients. Acknowledgment:The research was supported by the Public Technology Application Research Program of Zhejiang, China (LGF21H080003), the Key Project of Jinhua Science and Technology Plan, China (2020XG-29 and 2020-3-011), the Academician Workstation of the Fourth Affiliated Hospital of the Zhejiang University School of Medicine (2019-2024), the Key Medical Discipline of Yiwu, China (Hematology, 2018-2020) and the Key Medical Discipline of Jinhua, China (Hematology, 2019-2021). Correspondence to: Dr Jian Huang, Department of Hematology, The Fourth Affiliated Hospital of Zhejiang University School of Medicine. N1 Shangcheng Road. Yiwu, Zhejiang, Peoples R China. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.


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