Lateral Movement of the Entomopathogenic Nematodes Steinernema glaseri and Heterorhabditis bacteriophora in Sand at Different Temperatures in Response to Host Seeking

2002 ◽  
Vol 12 (1) ◽  
pp. 137-139 ◽  
Author(s):  
Attila S. Csontos
1998 ◽  
Vol 33 (1) ◽  
pp. 40-48 ◽  
Author(s):  
Monica L. Townsend ◽  
Donn T. Johnson ◽  
Don C. Steinkraus

In the laboratory, four nematode species differed significantly in the percentage mortality that each caused in second-instar green June beetles (grubs), Cotinis nitida (L.). Water suspensions of 1,000 infective juveniles (IJ)/one grub/Petri dish each of Heterorhabditis bacteriophora, Steinernema glaseri, and S. feltiae caused 34, 22 and 18% grub mortality, respectively. These values were significantly (P = 0.05) greater than the grub mortality caused by either S. carpocapsae (12%) or the water check (0%) that were similar. Several factors affected third- and fourth-instar susceptibility in the laboratory when exposed to 10,000 S. carpocapsae or H. bacteriophora IJ in 75 g of soil (133 IJ/cm3 soil)/plastic cup. Soil at 30% moisture by weight resulted in significantly more (P= 0.006) dead grubs (6.6%) than at 10% soil moisture (2.8%). Significantly more (P = 0.03) grubs died when at a grub density of 2 grubs/plastic cup (5.6%) than at 1 grub/plastic cup (3.8%). Significantly more (P = 0.01) grubs were killed by either S. carpocapsae and H. bacteriophora at a soil temperature of 25°C (6.5%) than at 12°C (2.8%). There was also a significant interaction of temperature and nematode species. Heterorhabditis bacteriophora killed significantly more (P= 0.02) grubs at 25°C (9.5%) than at 12°C (1.9%) and more than S. carpocapsae killed at either 12°C or 25°C (<3.9%). More virulent nematode strains or species than these four nematode species must be identified if green June beetles are to be controlled by nematodes.


Nematology ◽  
2014 ◽  
Vol 16 (9) ◽  
pp. 1047-1058 ◽  
Author(s):  
Jamileh Alvandi ◽  
Javad Karimi ◽  
Gary B. Dunphy

The haemocyte reactions of the white grub larvae Polyphylla adspersa to entomopathogenic nematodes (EPN), together with the host haemocyte types, have been studied. Six types of identified haemocytes included the prohaemocytes, granulocytes, plasmatocytes, oenocytoids, coagulocytes and spherulocytes. The granulocytes were the dominant (65.2%) haemocyte type followed by the plasmatocytes (22.1%). Both haemocyte types encapsulate EPN. White grub larvae and last larval stage of Galleria mellonella were individually infected with monoxenic Heterorhabditis bacteriophora or Steinernema glaseri. The maximum total haemocyte counts (THC) level of the white grub larvae against the nematode S. glaseri occurred at 12 h post-injection. In addition, by 8 h post-injection, the granulocyte and plasmatocyte levels decreased. The cell reactions of the grubs against H. bacteriophora in terms of THC and differential haemocyte counts and the encapsulation rate started earlier and were more pronounced than those against S. glaseri. The maximum percentage of the encapsulation observed in the white grub larvae against S. glaseri (27.3 ± 0.7%) and H. bacteriophora (36.5 ± 3.5%) occurred at 12 and 8 h post-injection, respectively. EPN-triggered encapsulation in P. adspersa larvae was more extensive than in G. mellonella larvae.


Nematology ◽  
2008 ◽  
Vol 10 (1) ◽  
pp. 137-141 ◽  
Author(s):  
I. Alper Susurluk

Abstract The vertical movement of Turkish isolates of Steinernema feltiae (TUR-S3) and Heterorhabditis bacteriophora (TURH2) was compared at different temperatures in the presence and absence of larvae of the host insect, Galleria mellonella. Nematodes of both species moved faster towards the bottom of the column when an insect was placed there. Steinernema feltiae showed greater vertical dispersal ability than H. bacteriophora. The vertical movement of both species increased as the temperature increased and lower temperatures depressed the movement of H. bacteriophora more than S. feltiae. The nematodes that had migrated different distances were compared for their infectivity to G. mellonella and the positive correlations between distance travelled and infectivity indicate that there is a link between host searching behaviour and infection behaviour in S. feltiae and, to a lesser extent, also in H. bacteriophora.


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.


Sign in / Sign up

Export Citation Format

Share Document