Observations of parasitoid behaviour in both no‐choice and choice tests are consistent with proposed ecological host range

Abstract Background The host specificity of the dry bean weevil, Acanthoscelides obtectus Say (Coleoptera: Bruchinae), a seed predator of beans, is not properly known. Occasional use of leguminous seeds other than beans is reported, however the sphere of possible wild and cultivated hosts is uncertain. Female oviposition preference and larval performance relationship is complicated by the respective importance of seed coat and cotyledon, because paradoxically, females must exercise oviposition preference on the basis of stimuli provided by the seed coat alone, without directly being able to assess the quality of cotyledon’s suitability for larval development.Results Host specificity and host range investigations carried out on seeds of 62 grown and naturally occurring legume species and 82 cultivars of Phaseolus, Pisum, Glycine, Lens and others in Hungary, using no-choice tests for egg-laying, and intact or pierced seed coat for larval development in seeds, showed that there were 18 plant species (35% of them Lathyrus) that supported larval development to adults, however, only nine species (4 of 17 Glycine max accessions, Vigna unguiculata, V. angularis, Phaseolus vulgaris, Ph. coccineus, Cicer arietinum, Vicia faba, Lathyrus sativus and 13 of 27 Pisum sativum accessions) allowed it if the seed coat was intact. Furthermore, there was no overall positive correlation between oviposition preference and larval performance, with the exception for the so-called acceptable non-hosts (Kendall’s τ = 0.3088). Bean weevil females also demonstrated an ovipositional hierarchy of legume species even in no-choice tests.Conclusions Host range expansion is not probable with the bean weevil, primarily because it would require the recognition of basically different oviposition substrates (pods) among outdoor conditions.

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ControllingLygusplant bugs (Heteroptera: Miridae) with EuropeanPeristenus relictus(Hymenoptera: Braconidae) in Canada – risky or not?

Bulletin of Entomological Research ◽

10.1079/ber2005414 ◽

2006 ◽

Vol 96 (2) ◽

pp. 187-196 ◽

Cited By ~ 16

Author(s):

T. Haye ◽

U. Kuhlmann ◽

H. Goulet ◽

P.G. Mason

Keyword(s):

Host Range ◽

Field Studies ◽

Minor Importance ◽

Target Species ◽

Northern Germany ◽

Target Populations ◽

Choice Tests ◽

Fundamental Host Range ◽

Parasitoid Development ◽

Natural Situation

AbstractThe EuropeanPeristenus relictusLoan (syn.P. stygicus) has been considered for biological control ofLygusplant bugs native to Canada. Laboratory and field studies were conducted in the area of origin to evaluate the host specificity ofP. relictus. Laboratory choice and no-choice tests demonstrated thatP. relictusattacked all non-target species offered (fundamental host range). However, closely related non-target mirids (tribe Mirini) were generally well accepted byP. relictus, while hosts from the tribe Stenodemini were less frequently attacked and less suitable for parasitoid development. To validate the laboratory results, a thorough examination of the parasitoid complex of common mirids in Europe was conducted to determine which non-target species may serve as alternative hosts forP. relictusin a natural situation (ecological host range). When comparing both approaches, the fundamental host range ofP. relictusmatched its ecological host range. In addition to threeLygusspecies, the ecological host range ofP. relictusin the area of Schleswig-Holstein, northern Germany, contains at least 16 non-target species, including hosts belonging to the subfamilies Mirinae, Phylinae and Bryocorinae. A broad ecological and fundamental host range suggests thatP. relictusis a generalist; however,P. relictuswas not the primary contributor to parasitism of most non-target hosts studied. AlthoughP. relictusis assumed to be of minor importance for regulating non-target populations in the area of investigation, the results of the present study indicate thatP. relictushas the potential to use non-target host populations for reproduction.

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Evaluation of the Physiological Host Range for the Parasitoid Ooencyrtus mirus, a Potential Biocontrol Agent of Bagrada hilaris

Insects ◽

10.3390/insects11070432 ◽

2020 ◽

Vol 11 (7) ◽

pp. 432 ◽

Cited By ~ 2

Author(s):

Nancy Power ◽

Fatemeh Ganjisaffar ◽

Thomas M. Perring

Keyword(s):

Host Range ◽

Biological Control Agent ◽

Developmental Time ◽

Egg Parasitoid ◽

Control Agent ◽

Plant Debris ◽

Brassica Plant ◽

Potential Biocontrol Agent ◽

Choice Tests ◽

The Mean

The thelytokous egg parasitoid Ooencyrtus mirus Triapitsyn and Power (Hymenoptera: Encyrtidae) was recovered from brassica plant debris in Pakistan in an effort to find a biological control agent of the invasive bug Bagrada hilaris (Burmeister) (Heteroptera: Pentatomidae) in North America. As the first step in determining the overall host range of this parasitoid, adult females were exposed to the eggs of eight alternate pentatomid host species, two non-pentatomid heteropterans, and two lepidopterans, in choice and no-choice tests. Although O. mirus was more successful on B. hilaris than the other species in terms of the number of the eggs laid, the number of emerged progeny, and the developmental time of the progeny, it was able to reproduce on all of the alternate hosts except for one of the lepidopterans, whose eggs appeared too small for this parasitoid. The results show O. mirus to be a generalist parasitoid species with a preference for B. hilaris. The results also indicate that there is a linear relationship between the mean body length of O. mirus females and the mean host egg weight with an adjusted R 2 of 0.90. The implications of this study on the release of O. mirus for the control of B. hilaris are discussed.

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