scholarly journals The suitability of biotypes Q and B ofBemisia tabaci(Gennadius) (Hemiptera: Aleyrodidae) at different nymphal instars as hosts forEncarsia formosaGahan (Hymenoptera: Aphelinidae)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1863 ◽  
Author(s):  
Xin Liu ◽  
Youjun Zhang ◽  
Wen Xie ◽  
Qingjun Wu ◽  
Shaoli Wang
Keyword(s):  
Biological Control ◽  
Feeding Rate ◽  
Trialeurodes Vaporariorum ◽  
Host Feeding ◽  
Encarsia Formosa ◽  
Greenhouse Crops ◽  
Commercial Strain ◽  
Promising Tool ◽  
Adult Parasitoid ◽  
Biotype B

Encarsia formosaGahan (Hymenoptera: Aphelinidae) is a solitary endoparasitoid that is commercially reared and released for augmentative biological control of whiteflies infesting greenhouse crops. In most areas in China, the invasive and destructive whiteflyBemisia tabaci(Gennadius) (Hemiptera: Aleyrodidae) biotype Q has replacedB. tabacibiotype B and has become dominant between the two. A better understanding of the suitability of different nymphal instars ofB. tabacibiotypes Q and B as hosts forE. formosais needed to improve the use of this parasitoid for biological control. Parasitism of the four nymphal instars ofB. tabacibiotypes Q and B by the commercial strain ofE. formosamass reared onTrialeurodes vaporariorum(Westwood) (Hemiptera: Aleyrodidae) was assessed in the laboratory. The results indicated thatE. formosaparasitized and successfully developed on all instars of both biotypes but performed best on the 3rd instar ofB. tabacibiotype B and on the 2nd, 3rd, and 4th instars ofB. tabacibiotype Q. The host-feeding rate of the adult parasitoid was generally higher on nymphal instars ofB. tabacibiotype Q than on the corresponding nymphal instars of biotype B and was significantly higher on the 2nd and 3rd instars. For both whitefly biotypes, the parasitoid’s immature developmental period was the longest on the 1st instar, intermediate on the 2nd and 3rd instars, and the shortest on the 4th instar. The parasitoid emergence rate was significantly lower on the 1st instar than on the other three instars and did not significantly differ betweenB. tabacibiotype B and biotype Q. Offspring longevity was greater on the 3rd and 4th instars than on the 1st instar and did not significantly differ between the twoB. tabacibiotypes. The results indicate that commercially-producedE. formosacan parasitize all instars ofB. tabacibiotypes B and Q, making this parasitoid a promising tool for the management of the two biotypes ofB. tabacipresent in China.

An Effect of Parasite Attack on Host Mortality, as Exemplified by Encarsia formosa and Trialeurodes vaporariorum

1962 ◽  
Vol 94 (7) ◽  
pp. 673-679 ◽  
Author(s):  
T. Burnett
Keyword(s):  
Field Tests ◽  
Trialeurodes Vaporariorum ◽  
Host Feeding ◽  
Encarsia Formosa ◽  
Mature Adult ◽  
Bracon Hebetor ◽  
Black Scale ◽  
Host Mortality ◽  
Host Parasite ◽  
Juvenilizing Effect

It is not unusual for parasite attack on insect hosts to have different consequences for individuals of the same species. An indication of the variation in types of alternative effects is given by a consideration of three host-parasite relationships. First, although most hosts in a population are susceptible to parasitization, some are immune to attack: about one in 3,000 larvae of the Mediterranean flour moth, Anagasta kühniella (Zeller), was found by Payne (1934) to be immune to attack by Bracon hebetor Say. Second, tile morphology of hosts may be modified differentially by parasitism: unhatched eggs of Aphdius platensis Brethes exert a juvenilizing effect on nymphs of Aphis craccivora Koch whereas parasite larvae sometimes cause the appearance of adult characters (Johnson, 1959). Third, some hosts are successfully parasitized whereas others are killed long before parasite progeny can mature: adult females of Metaphycus helvolus (Com.) kill the black scale, Saissetin oleae (Bern.), by parasitization, by mutilation with the ovipositor, and by host-feeding at wounds made by the ovipositor. Field tests showed that up to 97 per cent of a black-scale infestation may be killed by the parasite over a period of several months.

Encarsia species (Hymenoptera: Aphelinidae) of Australia and the Pacific Islands attacking Bemisia tabaci and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) – a pictorial key and descriptions of four new species

2001 ◽  
Vol 91 (5) ◽  
pp. 369-387 ◽  
Author(s):  
S. Schmidt ◽  
I.D. Naumann ◽  
P.J. De Barro
Keyword(s):  
Biological Control ◽  
Bemisia Tabaci ◽  
Pacific Islands ◽  
New Records ◽  
Trialeurodes Vaporariorum ◽  
Pacific Region ◽  
Biological Control Agents ◽  
The Pacific ◽  
Identification Of Species ◽  
Biotype B

AbstractAfter the recent introduction of the pest whitefly Bemisia tabaci (Gennadius) biotype B into Australia, research was undertaken to study the parasitoids of the long established native B. tabaci and Trialeurodes vaporariorum (Westwood). The genus Encarsia species which are important biological control agents of whiteflies and hard scales. The taxonomy of the Encarsia species attacking B. tabaci and T. vaporariorum in Australia and the Pacific Islands is revised. DNA sequencing of the 28S D2 ribosomal DNA was used characterize species. Sixteen species are recognized, with 12 occurring in Australia, eight in the Pacific region, and four in both regions. All except one species (E. formosa Gahan) are new records for Australia. Four species are described as new from Australia: E. accenta & Naumann sp. n., E. adusta Schmidt & Naumann sp. n., E. oakeyensis Schmidt & Naumann sp. n., and E. ustulata Schmidt & Naumann sp. n. Diagnostic descriptions are given for all species and each species is illustrated. pictorial key is provided to allow the identification of species by non-specialists.

scholarly journals Comparison of Biological and Chemical Control of Greenhouse Whitefly on Poinsettia Stock Plants

1992 ◽  
Vol 2 (4) ◽  
pp. 457-460 ◽  
Author(s):  
R.W. McMahon ◽  
R.K. Lindquist ◽  
M.L. Casey ◽  
A.C. Witt ◽  
S.H. Kinnamon
Keyword(s):  
Biological Control ◽  
Chemical Control ◽  
Trialeurodes Vaporariorum ◽  
Euphorbia Pulcherrima ◽  
Encarsia Formosa ◽  
Greenhouse Whitefly ◽  
Wild Stock ◽  
Control Compartment

A demonstration study was conducted to compare the effectiveness of biological and chemical control treatments on the greenhouse whitefly (GHWF) (Trialeurodes vaporariorum, Westwood) using poinsettia (Euphorbia pulcherrima Wild.) stock plants. Two identical greenhouse compartments, each containing 84 stock plants, were used. In the biological control compartment, three biweekly releases of Encarsia formosa (EF) were made, while in the chemical control compartment eight weekly applications of resmethrin or acephate aerosol treatments were made. Results showed that overall greenhouse whitefly populations in the chemical control compartment were slightly lower than in the biological control compartment. Cuttings taken from stock plants in the biological control compartment at the end of the experiment were commercially acceptable with regard to the presence of GHWF adults. Chemical names used: O,S-dimethyl acetylphosphoramidothioate (acephate), [5-(phenylmethyl)-3-furanyl] methyl 2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropane-carboxylate (resmethrin).

Variation in the Bemisia tabaci s. 1. species complex (Hemiptera: Aleyrodidae) and its natural enemies leading to successful biological control of Bemisia biotype B in the USA

2000 ◽  
Vol 90 (4) ◽  
pp. 317-327 ◽  
Author(s):  
A.A. Kirk ◽  
L.A. Lacey ◽  
J.K. Brown ◽  
M.A. Ciomperlik ◽  
J.A. Goolsby ◽  
...  
Keyword(s):  
Biological Control ◽  
Bemisia Tabaci ◽  
Species Complex ◽  
Release Site ◽  
Molecular Classification ◽  
Type B ◽  
Encarsia Formosa ◽  
Eretmocerus Mundus ◽  
The Usa ◽  
Biotype B

AbstractParasitoids of the Bemisia tabaci (Gennadius) species complex collected in Spain and Thailand were evaluated as biological control agents of B. tabacibiotype B in cole crops in Texas, USA. Parasitoids were identified by morphological and RAPD–PCR analyses. The most abundant parasitoid from Spain was Eretmocerus mundus Mercet with apparent field parasitism of 39–44%. In Thailand, Encarsia formosa Gahan, E. transvena Timberlake, E. adrianaeLopez-Avila, Eretmocerus sp. 1 and sp. 2 emerged, with apparent field parasitism of 1–65%. Identification and molecular classification of B. tabaciassociated with parasitoid collections and in the release site in Texas were accomplished using morphological traits and nucleotide sequence comparison of the mitochondrial cytochrome oxidase I gene (COI) (700–720 bp). Collections of B. tabacifrom Thailand grouped separately from B types from Arizona and Florida and the target B type from Texas, USA, a cluster from India, and other New World B. tabaci. The Spanish B. tabaci host of E. mundus which was laboratory and field-tested to achieve biological control of the B type was most closely related to non-B type B. tabaci populations from Spain and Sudan, the latter which formed a second group within the larger clade that also contained the B type cluster. Laboratory tests indicated that E. mundus from Spain parasitized more B. tabaci type B than did Eretmocerus spp. native to Texas and other exotic parasitoids evaluated. Eretmocerus mundus from Spain also successfully parasitized B. tabaci type B when field-released in a 0.94 million ha test area in Texas, and has significantly enhanced control of B. tabaci type B in California, USA. In contrast, parasitoids from Thailand failed to establish in the field in Texas, collectively suggesting a positive correlation between the centres of diversity of compatible parasitoid–host complexes.

Sign in / Sign up

Export Citation Format

Share Document