Nematology (2005) 7, 37-44

Sibylle Schroer, Xiaoli Yi and Ralf-Udo Ehlers (2005)
Evaluation of adjuvants for foliar application of Steinernema carpocapsae against larvae of the diamondback moth (Plutella xylostella)
Nematology 7 (1), 37-44
Abstract: Increasing resistance to chemical insecticides in field populations of the diamondback moth (Plutella xylostella) has stimulated research on alternative control measures. The entomopathogenic nematode Steinernema carpocapsae may be one such alternative, particularly against the third larval instar of P. xylostella. The LC₅₀ for the second instar is 38, the third 13 and the fourth 22 nematodes/larva. Plutella xylostella pupae were not affected by the nematodes, although mortality in leaf disk bioassays after application of nematodes in water seldom surpassed 50%. Therefore, additives were tested to improve nematode performance. Only Triton X-100 (0.3%) caused phytotoxic effects. The addition of xanthan gum or potassium alginate resulted in a two-fold increase of insect mortality at 80% relative humidity (RH) and a five-fold increase at 60% RH. Mixtures of 0.3% xanthan or alginate with 0.3% surfactants further improved efficacy. In water the LT₅₀ for S. carpocapsae against P. xylostella larvae was > 40 h. Using a mixture of 0.3% xanthan or 0.3% alginate with 0.3% surfactant, the LT₅₀ was reduced to < 25 h.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Ralf-Udo Ehlers

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
formulation/storage of bioagents
application technology

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Plutella xylostella
Steinernema carpocapsae/Xenorhabdus nematophila (entomopathogen)	Plutella xylostella