A Comparison of Varroa destructor (Acari: Varroidae) Collection Methods and Survivability in in Vitro Rearing Systems

Varroa destructor is the most important ectoparasitic mite of honey bees that has a negative impact on bee health and honey production. The control programs are mainly based on the use of synthetic acaricides that are often administered indiscriminately. All this has led to drug resistance that now represent a great concern for honey bee farming. The research for alternative products/methods for mites’ control is now mandatory. The aim of this study was to test whether Citrus spp. essential oils could diminish the growth of the V. destructor mite. In Calabria (southern Italy), plants of the Citrus genus are very common and grow both spontaneously and cultured. The essential oils used in this study were extracted from bergamot (Citrus bergamia), grapefruit (Citrus paradisi), lemon (Citrus limon), orange (Citrus sinensis), and mandarin (Citrus reticulata) by hydrodistillation. Every EO was in vitro tested against V. destructor. Each experimental replicate was performed using 35 viable adult female mites (5 for each EO) collected the same day from the same apiary and included negative controls (5 individuals exposed to acetone only) and positive controls (5 individuals exposed to Amitraz diluted in acetone). The essential oils (Eos) were diluted (0.5 mg/mL, 1 mg/mL, and 2 mg/mL) in HPLC grade acetone to obtain the working solution to be tested (50 µL/tube). Mite mortality was manually assessed after 1 h exposure under controlled conditions. The essential oils that showed the best effectiveness at 0.5 mg/mL were bergamot, which neutralized (dead + inactivated) 80% (p ≤ 0.001) of the parasites; grapefruit, which neutralized 70% (p ≤ 0.001); and lemon, which neutralized 69% of them. Interestingly, the positive control (Amitraz) at the same concentration neutralized 60% of the parasites. These results demonstrate that Calabrian bergamot, grapefruit, and lemon Eos consistently reduced V. destructor viability and open the possibility for their utilization to control this parasite in honey bee farming.

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In Vitro Rearing of the Larval Endoparasitoid, Venturia canescens (GRAVENHORST) (Hymenoptera: Ichneumonidae). : III Growth Promoting Ability of Extract of Galleria mellonella Pupae

Applied Entomology and Zoology ◽

10.1303/aez.32.91 ◽

1997 ◽

Vol 32 (1) ◽

pp. 91-99 ◽

Cited By ~ 12

Author(s):

Yuichi NAKAHARA ◽

Kikuo IWABUCHI ◽

Jun MITSUHASHI

Keyword(s):

Galleria Mellonella ◽

Venturia Canescens ◽

In Vitro Rearing ◽

Growth Promoting

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Using an in vitro system for maintaining Varroa destructor mites on Apis mellifera pupae as hosts: studies of mite longevity and feeding behavior

Experimental and Applied Acarology ◽

10.1007/s10493-018-0236-0 ◽

2018 ◽

Vol 74 (3) ◽

pp. 301-315 ◽

Cited By ~ 12

Author(s):

Noble I. Egekwu ◽

Francisco Posada ◽

Daniel E. Sonenshine ◽

Steven Cook

Keyword(s):

Apis Mellifera ◽

Feeding Behavior ◽

Varroa Destructor ◽

In Vitro System

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Salivary secretions from the honeybee mite, Varroa destructor: effects on insect haemocytes and preliminary biochemical characterization

Parasitology ◽

10.1017/s0031182011000072 ◽

2011 ◽

Vol 138 (5) ◽

pp. 602-608 ◽

Cited By ~ 31

Author(s):

E. H. RICHARDS ◽

BENJAMIN JONES ◽

ALAN BOWMAN

Keyword(s):

Wound Healing ◽

Honey Bee ◽

Varroa Destructor ◽

Biochemical Characterization ◽

Electrophoretic Analysis ◽

Cotton Wool ◽

Puncture Wound ◽

Molecular Weights ◽

Insect Haemocytes

SUMMARYIntroduction. The ectoparasitic honey bee mite Varroa destructor feeds on the haemolymph of the honey bee, Apis mellifera, through a single puncture wound that does not heal but remains open for several days. It was hypothesized that factors in the varroa saliva are responsible for this aberrant wound healing. Methods. An in vitro procedure was developed for collecting salivary gland secretions from V. destructor. Mites were incubated on balls of cotton wool soaked in a tissue culture medium (TC-100), and then induced to spit by topical application of an ethanolic pilocarpine solution. Results. Elution of secretions from balls of cotton wool, followed by electrophoretic analysis by SDS-PAGE and electroblotting indicated the presence of at least 15 distinct protein bands, with molecular weights ranging from 130 kDa to <17 kDa. Serial titration of V. destructor salivary secretions in TC-100 followed by an 18-h incubation with haemocytes from the caterpillar, Lacanobia oleracea, indicated that the secretions damage the haemocytes and suppresses their ability to extend pseudopods and form aggregates. Conclusion. We suggest that these secretions facilitate the ability of V. destructor to feed repeatedly off their bee hosts by suppressing haemocyte-mediated wound healing and plugging responses in the host.

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