scholarly journals Effect of Four Multiple Nucleopolyhedrovirus Isolates on the Larval Mortality and Development ofSpodoptera exigua(Lepidoptera: Noctuidae): Determination of Virus Production and Mean Time to Death

2018 ◽  
Vol 101 (2) ◽  
pp. 153-159
Author(s):  
Juan Carlos Luna-Espino ◽  
Víctor R. Castrejón-Gómez ◽  
Samuel Pineda ◽  
José Isaac Figueroa ◽  
Ana Mabel Martínez
Viruses ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 684 ◽  
Author(s):  
Paola E. Cuartas-Otálora ◽  
Juliana A. Gómez-Valderrama ◽  
Andrea E. Ramos ◽  
Gloria P. Barrera-Cubillos ◽  
Laura F. Villamizar-Rivero

The ability of the isolate VG008 of S. frugiperda granulovirus (SpfrGV) to enhance the infectivity of the isolate SfCOL of S. frugiperda multiple nucleopolyhedrovirus (SpfrMNPV) was evaluated on S. frugiperda larvae. Bioassays were performed with mixtures by using different proportions 90%:10% (M1), 95%:5% (M2) and 97.5%:2.5% (M3) of SfCOL:VG008, respectively. All mixtures showed higher insecticidal activity that SfCOL. The mixture M3 showed the highest enhancement of SfCOL reducing 11.40 times the Mean Lethal Concentration and 96 h in the Mean Time to Death. The enhancer activity of proteins derived from VG008 (GVPs) were also evaluated in mixture with SfCOL. The GVPs increased 27% larval mortality caused by SfCOL and damaged the peritrophic membrane of S. litura larvae, suggesting that the key point in this enhancing activity is the initial step of the larva colonization, the midgut infection. M3 was formulated and evaluated under greenhouse conditions in maize plants using different doses. The highest efficacy was obtained with the highest dose of M3 (8 × 1011 OBs/ha), which was similar to that found when formulated SfCOL was applied using an approximately twofold higher dose. The viral mixture M3 was selected as the active ingredient for developing a new biopesticide for a more efficient management of the pest in the field.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Ghulam Sarwar ◽  
Naeem Arshad Maan ◽  
Muhammad Ahsin Ayub ◽  
Muhammad Rafiq Shahid ◽  
Mubasher Ahmad Malik ◽  
...  

Abstract Background The armyworms, Spodoptera exigua (Hübner), and S. litura (Fabricius) (Lepidoptera: Noctuidae) are polyphagous pests of many cash crops. Heavy crop losses have been reported for the fruit and vegetable crops each year owing to the diverse impact on global economies. The present study was aimed to sort out a novel method of pest control using the insect’s own nucleopolyhedrosis virus (NPV) alone and in combination with a new chemistry insecticide chlorantraniliprole. Results In the study, the effect of indigenous isolated nucleopolyhedrovirus (NPV) and the chemical insecticide (chlorantraniliprole) formulations against the 2nd and 4th larval instars of S. litura and S. exigua, collected from the different geographical region of Punjab (Pakistan) province, was evaluated. Three concentrations of the NPV isolate, sub-lethal (1 × 104, 6 × 104 POB ml−1), lethal (3 × 105 POB ml−1), and chlorantraniliprole 0.01 μl l−1, were applied alone and in combination against the 2nd and 4th larval instars of both pest species. The lethal concentration of NPV + chlorantraniliprole exhibited synergistic interaction and caused high larval mortality against both instars, while in all other combinations, additive effect was observed. Moreover, NPV + chlorantraniliprole at lethal concentration exhibited decreased pupation, adult emergence, and egg eclosion. Conclusion The implications of using NPV alone and in combination with an insecticide are discussed briefly in this study.


2021 ◽  
pp. 107815522110160
Author(s):  
Bernadatte Zimbwa ◽  
Peter J Gilbar ◽  
Mark R Davis ◽  
Srinivas Kondalsamy-Chennakesavan

Purpose To retrospectively determine the rate of death occurring within 14 and 30 days of systemic anticancer therapy (SACT), compare this against a previous audit and benchmark results against other cancer centres. Secondly, to determine if the introduction of immune checkpoint inhibitors (ICI), not available at the time of the initial audit, impacted mortality rates. Method All adult solid tumour and haematology patients receiving SACT at an Australian Regional Cancer Centre (RCC) between January 2016 and July 2020 were included. Results Over a 55-month period, 1709 patients received SACT. Patients dying within 14 and 30 days of SACT were 3.3% and 7.0% respectively and is slightly higher than our previous study which was 1.89% and 5.6%. Mean time to death was 15.5 days. Males accounted for 63.9% of patients and the mean age was 66.8 years. 46.2% of the 119 patients dying in the 30 days post SACT started a new line of treatment during that time. Of 98 patients receiving ICI, 22.5% died within 30 days of commencement. Disease progression was the most common cause of death (79%). The most common place of death was the RCC (38.7%). Conclusion The rate of death observed in our re-audit compares favourably with our previous audit and is still at the lower end of that seen in published studies in Australia and internationally. Cases of patients dying within 30 days of SACT should be regularly reviewed to maintain awareness of this benchmark of quality assurance and provide a feedback process for clinicians.


Trauma ◽  
2021 ◽  
pp. 146040862094972
Author(s):  
Ahmed Fadulelmola ◽  
Rob Gregory ◽  
Gavin Gordon ◽  
Fiona Smith ◽  
Andrew Jennings

Introduction: A novel virus, SARS-CoV-2, has caused a fatal global pandemic which particularly affects the elderly and those with comorbidities. Hip fractures affect elderly populations, necessitate hospital admissions and place this group at particular risk from COVID-19 infection. This study investigates the effect of COVID-19 infection on 30-day hip fracture mortality. Method: Data related to 75 adult hip fractures admitted to two units during March and April 2020 were reviewed. The mean age was 83.5 years (range 65–98 years), and most (53, 70.7%) were women. The primary outcome measure was 30-day mortality associated with COVID-19 infection. Results: The COVID-19 infection rate was 26.7% (20 patients), with a significant difference in the 30-day mortality rate in the COVID-19-positive group (10/20, 50%) compared to the COVID-19-negative group (4/55, 7.3%), with mean time to death of 19.8 days (95% confidence interval: 17.0–22.5). The mean time from admission to surgery was 43.1 h and 38.3 h, in COVID-19-positive and COVID-19-negative groups, respectively. All COVID-19-positive patients had shown symptoms of fever and cough, and all 10 cases who died were hypoxic. Seven (35%) cases had radiological lung findings consistent of viral pneumonitis which resulted in mortality (70% of mortality). 30% ( n = 6) contracted the COVID-19 infection in the community, and 70% ( n = 14) developed symptoms after hospital admission. Conclusion: Hip fractures associated with COVID-19 infection have a high 30-day mortality. COVID-19 testing and chest X-ray for patients presenting with hip fractures help in early planning of high-risk surgeries and allow counselling of the patients and family using realistic prognosis.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Gurmehar Kaur Grewal ◽  
Neelam Joshi ◽  
Yadhu Suneja

Abstract Background Spodoptera litura (Fab.) (Lepidoptera: Noctuidae) is a serious agricultural pest that infests many commercially important crops of Southeast Asian countries. Indiscriminate use of chemical pesticides has led to various health hazards as well as insecticide resistance. Entomopathogenic fungi (EPF) provide an important alternative as biological control agents. Metarhizium rileyi is an EPF with a specific host range for lepidopteran pests. The present study aimed to identify virulent M. rileyi isolate against S. litura larvae and analyse their extracellular cuticle-degrading enzyme activities. Results Three M. rileyi isolates viz M. rileyi NIPHM, M. rileyi MTCC 4254 and M. rileyi MTCC 10395 formulations were evaluated at different concentrations against 2nd instar larvae of S. litura. A maximum percent mortality of 63.33% was recorded in M. rileyi NIPHM (12 g/l), followed by M. rileyi MTCC 4254 (58.33%) at the same concentration, 10 days post-treatment. Maximum means of chitinase, protease and lipase activities (0.44, 1.58 and 2.95 U/ml, respectively) were recorded in the case of M. rileyi NIPHM. Correlation analysis was positive between enzyme activity and larval mortality. Conclusions Metarhizium rileyi NIPHM recorded the highest enzymatic activity and exhibited the maximum mortality rate against 2nd instar larvae of S. litura, suggesting the possible role of these enzymes in the pathogenicity of the fungus. Further knowledge in this regard may help in the development of enzyme-based screening methods for selecting virulent fungal isolates for the eco-friendly management of crop pests.


Author(s):  
Eman Mohammed Abd-ElAzeem ◽  
Warda Ahmed Zaki El-Medany ◽  
Hend Mohammed Sabry

AbstractBiological activities of spores and metabolites of some fungi isolated from dead larva of the spiny bollworms (SBW), Earias insulana (Boisd.) (Lepidoptera: Noctuidae), against the newly hatched larvae of the pest were carried out. Results showed that the fungi Metarhizium anisopliae, Acremonium sp., and Paecilomyces variotii had affected the newly hatched larvae of (SBW). Acremonium sp. was the most potent one as it had the highest newly hatched larval mortality percentage (65 and 58.33%) for its spore suspension and metabolites, respectively, while the lowest one (41%) was for P. variotii metabolites. Also, spore suspensions of the all fungal isolates had the highest larval mortality than fungal metabolites. Studying the enzymatic activity showed that Acremonium sp. produced protease enzyme on media containing gelatin, which caused the highest larval mortality (72.22%).These isolates showed different effects on all stages of the pest and decreased pupal weight, adult emergence percentages, deposited eggs, and hatchability percentages than the control. Identification of Acremonium sp. EZ1 was confirmed using 18 s rRNA and its accession number MN25101.


2012 ◽  
Vol 56 (12) ◽  
pp. 6328-6333 ◽  
Author(s):  
Donald F. Smee ◽  
Mark von Itzstein ◽  
Beenu Bhatt ◽  
E. Bart Tarbet

ABSTRACTCompounds lacking oral activity may be delivered intranasally to treat influenza virus infections in mice. However, intranasal treatments greatly enhance the virulence of such virus infections. This can be partially compensated for by giving reduced virus challenge doses. These can be 100- to 1,000-fold lower than infections without such treatment and still cause equivalent mortality. We found that intranasal liquid treatments facilitate virus production (probably through enhanced virus spread) and that lung pneumonia was delayed by only 2 days relative to a 1,000-fold higher virus challenge dose not accompanied by intranasal treatments. In one study, zanamivir was 90 to 100% effective at 10 mg/kg/day by oral, intraperitoneal, and intramuscular routes against influenza A/California/04/2009 (H1N1) virus in mice. However, the same compound administered intranasally at 20 mg/kg/day for 5 days gave no protection from death although the time to death was significantly delayed. A related compound, Neu5Ac2en (N-acetyl-2,3-dehydro-2-deoxyneuraminic acid), was ineffective at 100 mg/kg/day. Intranasal zanamivir and Neu5Ac2en were 70 to 100% protective against influenza A/NWS/33 (H1N1) virus infections at 0.1 to 10 and 30 to 100 mg/kg/day, respectively. Somewhat more difficult to treat was A/Victoria/3/75 virus that required 10 mg/kg/day of zanamivir to achieve full protection. These results illustrate that treatment of influenza virus infections by the intranasal route requires consideration of both virus challenge dose and virus strain in order to avoid compromising the effectiveness of a potentially useful antiviral agent. In addition, the intranasal treatments were shown to facilitate virus replication and promote lung pathology.


Sign in / Sign up

Export Citation Format

Share Document