scholarly journals Additive interactions of some reduced-risk biocides and two entomopathogenic nematodes suggest implications for integrated control of Spodoptera litura (Lepidoptera: Noctuidae)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rashad Rasool Khan ◽  
Muhammad Arshad ◽  
Asad Aslam ◽  
Muhammad Arshad
Keyword(s):  
Entomopathogenic Nematodes ◽  
Integrated Control ◽  
Positive Control ◽  
Emamectin Benzoate ◽  
Chi Square ◽  
Insecticide Mixtures ◽  
Resistant Strains ◽  
Additive Interactions ◽  
Lepidoptera Noctuidae ◽  
Reduced Risk

AbstractHigher volumes of conventional and novel chemical insecticides are applied by farmers to control resistant strains of armyworm (Spodoperta litura) in Pakistan without knowing their risks to the environment and to public health. Ten reduced-risk insecticides were tested for their compatibility with two entomopathogenic nematodes (EPNs); Heterorhabditis indica and Steinernema carpocapsae against S. litura. The insecticide emamectin benzoate was highly toxic (LC50 = 2.97 mg/l) against 3rd instar S. litura larvae when applied alone whereas, novaluron and methoxyfenozide were the least toxic (LC50 = 29.56 mg/l and 21.06 mg/l), respectively. All the insecticides proved harmless against the two EPNs even 96 h after treatment. Indoxacarb, flubendiamide and spinetoram produced the greatest mortalities (72–76%) of S. litura larvae after 72 h when applied in mixtures with H. indica. Lowest mortalities (44.00 ± 3.74% and 48.00 ± 2.89) were observed for mixtures of H. indica with methoxyfenozide and chlorfenapyr, respectively. The positive control treatments with both EPNs (S. carpocapsae and H. indica) produced > 50% mortality 96 h after treatment. For insecticide mixtures with S. carpocapsae, only indoxacarb produced 90% mortality of larvae, whereas, indoxacarb, flubendiamide, emamectin benzoate, and spinetoram produced 90–92% mortality of larvae when applied in mixtures with H. indica. Additive interactions (Chi-square < 3.84) of EPN mixtures with reduced volumes of reduced-risk insecticides suggest opportunities to develop more environmentally favorable pest management programs for S. litura.

scholarly journals Integrated Control of Fall Armyworm (Lepidoptera: Noctuidae) Using Resistant Plants and Entomopathogenic Nematodes (Rhabditida: Steinernematidae)

1999 ◽  
Vol 82 (2) ◽  
pp. 263 ◽  
Author(s):  
J. Molina-Ochoa ◽  
R. Lezama-Gutierrez ◽  
J. J. Hamm ◽  
B. R. Wiseman ◽  
M. Lopez-Edwards
Keyword(s):  
Entomopathogenic Nematodes ◽  
Integrated Control ◽  
Fall Armyworm ◽  
Lepidoptera Noctuidae

Efficacy of entomopathogenic nematodes (Nematoda: Rhabditida) and insecticide mixtures to control Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) in corn crops

2010 ◽  
Vol 29 (7) ◽  
pp. 677-683 ◽  
Author(s):  
Aldomario S. Negrisoli ◽  
Mauro S. Garcia ◽  
Carla R.C. Barbosa Negrisoli ◽  
Daniel Bernardi ◽  
Alexandre da Silva
Keyword(s):  
Spodoptera Frugiperda ◽  
Entomopathogenic Nematodes ◽  
Insecticide Mixtures ◽  
Lepidoptera Noctuidae

scholarly journals Isolation of entomopathogenic nematodes in an apple orchard in Southern Brazil and its virulence to Anastrepha fraterculus (Diptera: Tephritidae) larvae, under laboratory conditions

2017 ◽  
Vol 77 (1) ◽  
pp. 22-28 ◽  
Author(s):  
E. Foelkel ◽  
M. Voss ◽  
L. B. Monteiro ◽  
G. Nishimura
Keyword(s):  
Entomopathogenic Nematodes ◽  
Abiotic Factors ◽  
Integrated Control ◽  
Weather Conditions ◽  
Apple Orchard ◽  
Soil Samples ◽  
Similar Frequency ◽  
Promising Alternative ◽  
Climate Conditions ◽  
Anastrepha Fraterculus

Abstract Entomopathogenic nematodes (EPNs) are a promising alternative to integrated control in many fruit pests. Few studies were made on the relationship of Anastrepha fraterculus natural population with native EPNs population and other biotic and abiotic factors. The aim of this work was to verify the occurrence of endemic nematodes in an apple orchard, concerning environmental conditions and technical procedure, and access isolates virulence to A. fraterculus larvae. The experiment was conducted during a year taking monthly soil samples from an apple orchard, with and without fallen fruits just above the soil. Samples were baited with Tenebrium molitor and A. fraterculus larvae in laboratory. Canopy and fallen fruits were sampled to access the pest infestation. Seventy three EPN isolates were captured, in 23.2% soil samples, more with T. molitor than with A. fraterculus baits. From the 20 isolates tested against A. fraterculus, only five were pathogenic, and they were identified as Oscheius sp. The nematodes were captured during all seasons in a similar frequency. Soil and weather conditions, presence of fruit over the orchard soil, and A. fraterculus pupae in the fruits had no significant influence on the capture. As a conclusion, nematodes of the genera Oscheius are found in an apple orchard of Porto Amazonas constantly along the year, independently of fluctuations in A. fraterculus population, climate conditions and presence of fruit over the soil. Some of the isolates are pathogenic to A. fraterculus.

322 EFFECT OF PLASMIN ON ACROSOME REACTION OF BUFFALO (BUBALUS BUBALIS) SPERMATOZOA IN VITRO

2010 ◽  
Vol 22 (1) ◽  
pp. 317
Author(s):  
I. Venditto ◽  
E. Mariotti ◽  
L. Boccia ◽  
M. Rubessa ◽  
M. De Blasi ◽  
...  
Keyword(s):  
Acrosome Reaction ◽  
Proteolytic Enzymes ◽  
Critical Role ◽  
Bubalus Bubalis ◽  
Positive Control ◽  
Negative Control ◽  
Chi Square ◽  
Chi Square Test ◽  
Response Trial

Fertilization is a critical step of the in vitro embryo production (IVEP) technology in buffalo. It is known that proteolytic enzymes are involved in different steps of the fertilization process; among these, a critical role may be played by the plasminogen activator-plasmin system. It has been demonstrated that plasmin, the active enzyme of this system, induces acrosome reaction (AR) in bull spermatozoa (Taitzoglou IA et al. 2003 Andrologia 35, 112-116). The aim of this study was to investigate the effect of plasmin on the ability of buffalo sperm to undergo the AR. Frozen- thawed sperm from 4 buffalo bulls were treated by swim-up and incubated with 0.01 mM heparin for 4 h. At 0, 2, and 4 h, aliquots of spermatozoa were exposed for 10 min to 60 μg mL-1 of lysophosphatidylcholine (LPC), as positive control, and to 0.01 μg mL-1 of plasmin. This concentration was chosen after a preliminary dose-response trial. Another sample from each treatment was incubated with IVF medium (negative control). After 10 min, sperm motility was evaluated and sperm were fixed in 37% formaldehyde and stained with trypan blue-Giemsa for subsequent microscopic examination. The total number of sperm counted, over 3 replicates, was 1269 for the negative control, 1293 for LPC, and 1238 for plasmin, equally distributed among incubation times. Differences among groups were analyzed by chi-square test. After swim-up, acrosomal loss was observed only in 4% of the sperm. The addition of 0.01 μg mL-1 of plasmin for 10 min to buffalo spermatozoa at time 0 significantly (P < 0.01) enhanced (23%) AR compared with the control (7.8%), with the same efficiency of LPC (17.1%). After 2 h of incubation with heparin, both plasmin and LPC increased the AR compared to the control (24.4, 20.1, and 14.0%, respectively; P < 0.01). After 4 h, plasmin gave higher percentages of AR (27.2%) compared to both the control (21.0%; P < 0.05) and LPC (19.2%; P < 0.01). Another interesting result is the improved motility recorded with plasmin compared to both the control and LPC groups at 2 h of incubation (90, 75, and 75%, respectively; P < 0.05) and at 4 h of incubation (75, 60, and 60%, respectively; P < 0.05). Finally, no differences in sperm viability were observed between plasmin and the control, whereas a decreased viability was found when LPC was used at 0 h (96.2, 95.0, and 89.0%, respectively, for plasmin, control, and LPC; P < 0.05), at 2 h (85.0, 87.5, and 77.0%, respectively, for plasmin, control, and LPC; P < 0.01), and at 4 h (85.0, 93.3, and 81.1%, respectively, for plasmin, control, and LPC; P < 0.01). In conclusion, we found that addition of plasmin to capacitated sperm increases the percentage of acrosome-reacted spermatozoa and improves motility. Our results suggest that plasmin may play a role in events surrounding fertilization and suggest to evaluate in further studies whether the addition of plasmin during IVF improves the IVEP efficiency in buffalo.

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