Virulence of two entomopathogenic nematode species, Steinernema sp. (strain PQ16) and Heterorhabditis indica (strain KT3987), to nymphs of the coffee cicada Dundubia nagarasingna

Nematology ◽  
2019 ◽  
Vol 21 (1) ◽  
pp. 35-44 ◽  
Author(s):  
Chau N. Nguyen ◽  
Anh T. Do ◽  
Phap Q. Trinh ◽  
Phuc K. Hoang

Summary The virulence and efficacy of two species of entomopathogenic nematodes, Steinernema sp. (strain PQ16) and Heterorhabditis indica (strain KT3987), against nymphs of the coffee cicada, Dundubia nagarasingna, was evaluated under laboratory and glasshouse conditions. The highest mortality rates of coffee cicada nymphs caused by these two nematode strains were 93.5 and 100%, respectively, at an inoculation dose of 600 infective juveniles (IJ) nymph−1. The virulence (LC50) was established as 137.5 IJ and 149.1 IJ for strains S-PQ16 and H-KT3987, respectively. The highest IJ yields of these nematode strains were 66 × 103 IJ (for S-PQ16) and 134.4 × 103 IJ (for H-KT3987) at a dose of 500 IJ nymph−1. The efficacies of the two nematode strains to coffee cicadas at treated dose of 60 × 103 IJ pot−1 were 84.4 and 88.9% after 30 days, higher than the efficacies at treated dose of 40 × 103 IJ pot−1. The number of IJ in 250 ml of soil at 10, 20 and 30 days after treatment, increased from 0.38 × 103 to 4.80 × 103 IJ in soil treated with a dose of 40 × 103 IJ and from 0.66 × 103 to 5.02 × 103 IJ in soil treated with a dose of 60 × 103 IJ (for S-PQ16). Similarly, for H-KT3987 the number of IJ increased from 0.43 × 103 to 8.99 × 103 IJ and from 0.62 × 103 to 9.64 × 103 IJ, at the respective doses. Based on results of a pot trial from glasshouse modelling, an IJ application dosage for biological control of coffee cicada nymphs in coffee plantations was proposed.

2017 ◽  
Vol 38 (02) ◽  
Author(s):  
Gitanjali Devi ◽  
Dhrubajyoti Nath

Biological control agents have become increasingly important component in integrated pest management programme. Entomopathogenic nematodes are effective biological control agents for many important insect pests of vegetable crops. Therefore entomopathogenic nematodes are gaining attention in the field of biocontrol research worldwide. With the development and improvement of isolation and identification technique many novel species and strains have been utilized for management of several insect pests. This review aims to explore the potentiality of entomopathogenic nematode species against economically important insect pest of vegetables in India as well as in other countries.


2008 ◽  
Vol 18 (1) ◽  
pp. 84-89 ◽  
Author(s):  
Erick X. Caamano ◽  
Raymond A. Cloyd ◽  
Leellen F. Solter ◽  
Declan J. Fallon

The quality of entomopathogenic nematodes (EPN) is critical to their success as biological control agents, but it is difficult to evaluate quality because standard procedures are not available. Generally, the quality of biological control agents is determined by field performance because end users may have minimal knowledge pertaining to the condition of biological control agents before application. This study assessed the variability in quality of commercially available EPN products. The authors evaluated preapplication survival of five EPN formulations, Steinernema feltiae (NemaShield, Nemasys, Gnat Not, Horticultural Scanmask), and Heterorhabditis indica (GrubStake-Hi), based on eight shipments/samples of each EPN product received during a 5-month period (July to November). The estimated total number of EPN delivered per shipment (i.e., sample) was compared with the expected quantity listed on the label, and percent live EPN was determined for each shipment. One-half of the shipments of Gnat Not (four of eight) contained 40% to 70% of the number of EPN expected based on the label (25 million). The remaining shipments contained consistently higher numbers, with 99% of the expected quantity of EPN received. Entomopathogenic nematode mean percent survival was highest for Nemasys (98%) and lowest for Horticultural Scanmask (56%). The overall mean percent survival for Gnat Not and GrubStake-Hi, both from the same supplier, was more than 85%. Survival of EPN in the NemaShield product was as low as 50%, but was typically between 65% and 75%. NemaShield and Nemasys were the only two EPN products that provided return policy information if the product was damaged in any way. It is important for distributors and suppliers to ensure that EPN products are in quality condition before shipping to avoid performance failures and loss of customers. In addition, end users need to evaluate shipments upon receipt to determine the viability of EPN products.


2010 ◽  
Vol 54 (3) ◽  
pp. 166-171 ◽  
Author(s):  
Z. Ipek Ekmen ◽  
Selcuk Hazir ◽  
Ibrahim Cakmak ◽  
Nurdan Ozer ◽  
Mehmet Karagoz ◽  
...  

2011 ◽  
Vol 35 (6) ◽  
pp. 1149-1156 ◽  
Author(s):  
Viviane Santos ◽  
Alcides Moino Junior ◽  
Vanessa Andaló ◽  
Camila Costa Moreira ◽  
Ricardo Alves de Olinda

Entomopathogenic nematodes (EPNs) are used in biological control of soil insects and show promise in the control of D. speciosa. The objective of this work was to evaluate the potential of native and exotic entomopathogenic nematode isolates in the control of D. speciosa under laboratory and greenhouse conditions. Results showed that all of EPNs caused larval mortality. The most virulent were Heterorhabditis sp. RSC01 (94%), Steinernema glaseri (84%), Heterorhabditis sp. JPM04 (82%) and Heterorhabditis amazonensis RSC05 (78%). There was no effect of the Heterorhabditis sp. RSC01 and S. glaseri isolates on eggs. The maximum mortality of D. speciosa larvae by Heterorhabditis sp. RSC01 was observed at a concentration of 300 IJ/ insect, while by S. glaseri observed the highest mortality at the concentration of 200 IJ/ insect. The Heterorhabditis sp. RSC01 isolate caused over 80% pupal mortality at a concentration of 250 IJ/insect. The virulence of Heterorhabditis sp. RSC01 and S. glaseri was affected by temperature. The Heterorhabditis sp. RSC01 isolate caused reduction in larva survival under greenhouse conditions at all of the tested concentrations and there was no difference in mortality among different concentrations of infectid juveniles.


Parasitology ◽  
1996 ◽  
Vol 113 (5) ◽  
pp. 473-482 ◽  
Author(s):  
J. F. Campbell ◽  
E. Lewis ◽  
F. Yoder ◽  
R. Gaugler

SUMMARYUnderstanding the temporal and spatial distribution of entomopathogenic nematodes is essential for determining the role of these insect parasites in soil communities and ultimately for their use in suppression of pest insect populations. We measured the vertical and horizontal distribution of endemic populations of entomopathogenic nematodes (Steinernema carpocapsae and Heterorhabditis bacteriophord) in turfgrass. Vertical distribution was determined by taking soil cores every 3 h from 05.00 to 23.00 h, over 4 days, and dividing the cores into 8, 1 cm deep sections. Steinernema carpocapsae was recovered primarily near the soil surface: 50% of positive sections were recovered in the thatch or first 1 cm of soil. S. carpocapsae recovery was lower during the middle of the day and none were recovered in the upper section. H. bacteriophora was recovered uniformly throughout the top 8 cm of soil and its vertical distribution did not change over the course of the day. Horizontal distribution was measured as the number of nematodes recovered from cores taken from 12 randomly selected 0·3 × 0·8 m sections from within four 15·3 × 15·3 m plots. Samples were collected biweekly over a 9-month period. H. bacteriophora had a patchier distribution than S. carpocapsae and both nematode species had more patchy distributions then their potential hosts. Our results support the hypothesis that these two species of nematode utilize different foraging strategies; S. carpocapsae primarily a surface adapted ambusher and H. bacteriophora as a cruise forager.


Nematology ◽  
2016 ◽  
Vol 18 (9) ◽  
pp. 1045-1052 ◽  
Author(s):  
Jagadeesh Patil ◽  
Vijayakumar Rangasamy ◽  
Abraham Verghese

Holotrichia consanguinea is a serious pest of peanut and sugarcane that attacks other commercial crops in India. The efficacy of two species of entomopathogenic nematodes (EPN), Steinernema abbasi and Heterorhabditis indica, against H. consanguinea was tested under laboratory and field conditions. In a laboratory assay, H. indica caused significantly greater mortality (25-100%) than S. abbasi (20-80%) against second instars and H. indica caused 17.5-82.5% mortality in third-instar grub larvae, while S. abbasi caused (10-60%) mortality. These results revealed that second-instar grubs were more susceptible than third-instar grubs and efficacy of EPN against H. consanguinea varies with nematode species. The penetration and multiplication rate for H. indica was significantly higher than those of S. abbasi. Infective juveniles (IJ) of both nematode species and a commonly used insecticide (phorate) were tested against this insect in a field experiment. Field trail data showed that the percentage reduction in H. consanguinea grub population was significantly higher using H. indica at a dose of 2.5 × 109 IJ ha−1 than S. abbasi and phorate application. Phorate application was more efficient in reducing the grub population than both nematode species at the lower application rate (1.25 × 109 IJ ha−1). Overall, these experiments suggest that H. indica may be a promising biocontrol agent against H. consanguinea.


Author(s):  
Américo de Castro Monteiro Sobrinho ◽  
Isadora Luiza Alves Costa ◽  
Graziele Calixto Souza ◽  
Luís Carlos de Souza Rodrigues Leal ◽  
João Luiz Lopes Monteiro Neto ◽  
...  

Abstract Stomoxys calcitrans is a hematophagous dipteran. Several agents are used in biological control, including entomopathogenic nematodes (EPNs). Bioassay I involved an evaluation of the effect of Heterorhabditis bacteriophora HP88 and Heterorhabditis baujardi LPP7 on S. calcitrans larvae in different periods of exposure. Groups of 10 larvae were placed in Petri dishes and 200 EPNs/larva were added, which were divided into groups according to the exposure times of 2, 4, 6, 12, 24 and 48 hours. The purpose of Bioassay II was to evaluate the efficacy of the EPNs in infecting S. calcitrans larvae when they were isolated from stable fly larvae in Bioassay I. Groups of 10 larvae were placed in Petri dishes and 200 EPNs/larva were added. In bioassay I, H. bacteriophora caused mortality rates of 51.7, 83.3 and 91.7% in 12, 24 and 48 hours, respectively, while H. baujardi caused mortality rates of 9.3 (12h), 35 (24h) and 35% (48h). In Bioassay II, H. bacteriophora and H. baujardi resulted in mortality rates of 35% and 25%, respectively. It was concluded that the longest exposure times presented the highest larval mortality and that EPNs isolated from S. calcitrans are not efficient in controlling the larvae fly.


2021 ◽  
Vol 18 (1) ◽  
pp. 205-215
Author(s):  
Dirceu Pratissoli ◽  
ALIXELHE PACHECO DAMASCENA ◽  
Débora Melo Ferreira Fragoso ◽  
José Romário De Carvalho ◽  
Amanda Carlos Túler ◽  
...  

The use of entomopathogenic nematodes in pest management is an alternative to reduce the yield and/or damage losses caused by pests in several crops. The present study aimed to evaluate the performance of Heterorhabditis indica (Nemata: Rhabditida) and Steinernema carpocapsae (Nemata: Rhabditida), in pre-pupae of Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) and determine the temporal viability of the pathogenicity of S. carpocapsae applied to soil. The nematode species were diluted in distilled water to 50, 65, 83, 107, 138, 178, 229, 295, 380 and 500 infective juveniles per pre-pupae (IJs insect-1) of N. elegantalis.  The mortality of pre-pupa of N. elegantalis was higher as the concentrations of both studied species increased. The nematode S. carpocapsae was the most effective, causing mortality of 82.93% in the concentration of 65 IJs insect-1 and an LC50 of 24.32 IJs insect-1. In the pathogenicity test, S. carpocapsae was applied in the concentration of 100 JI/cm² in pots previously planted with tomato seedlings. As positive control was used tomato seedlings treated with distilled water. S. carpocapse presented soil viability of 24 days. Thus, S. carpocapsae can be an important tool in the integrated pest management (IPM) of N. elegantalis.


2005 ◽  
Vol 95 (5) ◽  
pp. 473-482 ◽  
Author(s):  
S. Toepfer ◽  
C. Gueldenzoph ◽  
R.-U. Ehlers ◽  
U. Kuhlmann

AbstractEntomopathogenic nematode species available in Europe were screened for their efficacy against both the root-feeding larvae and silk-feeding adults of the western corn rootworm, Diabrotica virgifera virgifera LeConte. Laboratory screening tests were aimed at the selection of candidate biological control agents for the management of this invasive alien pest in Europe. Steinernema glaseri, S. arenarium, S. abassi, S. bicornutum, S. feltiae, S. kraussei, S. carpocapsae and Heterorhabditis bacteriophora were studied to determine their virulence against third instar larvae and adults of D. v. virgifera in small-volume arenas (using nematode concentrations of 0.5, 0.8, 7.9 and 15.9 infective juveniles cm–2). All nematode species were able to invade and propagate in D. v. virgifera larvae, but adults were rarely infected. At concentrations of 7.9 and 15.9 cm–2, S. glaseri, S. arenarium, S. abassi and H. bacteriophora caused the highest larval mortality of up to 77%. Steinernema bicornutum, S. abassi, S. carpocapsae and H. bacteriophora appeared to have a high propagation level, producing 5970±779, 5595±811, 5341±1177 and 4039±1025 infective juveniles per larva, respectively. Steinernema glaseri, S. arenarium, S. feltiae, S. kraussei and H. bacteriophora were further screened at a concentration of 16.7 nematodes cm–2 against third instar larvae in medium-volume arenas (sand-filled trays with maize plants). Heterorhabditis bacteriophora, S. arenarium and S. feltiae caused the highest larval mortality with 77±16.6%, 67±3.5%, and 57±17.1%, respectively. In a next step, criteria for rating the entomopathogenic nematode species were applied based on results obtained for virulence and propagation, and for current production costs and availability in Europe. These criteria were then rated to determine the potential of the nematodes for further field testing. Results showed the highest potential in H. bacteriophora, followed by S. arenarium and S. feltiae, for further testing as candidate biological control agents.


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