Adult Survival ofDelphastus catalinae(Coleoptera: Coccinellidae), a Predator of Whiteflies (Hemiptera: Aleyrodidae), on Diets of Whiteflies, Honeydew, and Honey

Abstract

Delphastus catalinae (Horn) is a coccinellid predator that is commercially sold for the management of whiteflies. A study was conducted to assay the effect of selected diets on the survival of adult D. catalinae. Treatments of water (as a control), 10% honey, honeydew, and whiteflies [Bemisia tabaci (Gennadius)] were provided to the beetles in laboratory assays. Newly emerged, unfed adult insects were used at the start of a survival experiment with trials lasting 50 d. Another survival experiment used mixed-aged adults from a greenhouse colony, and the trials lasted 21 d. Survival was poor on a diet of solely water; ~1% survived beyond a week at 26°C. Survival using the newly emerged insects was similar between those fed honeydew and honey diets, but those on the whitefly diet had the greatest survival (~60% on day 50). However, in the experiment with mixed-aged beetles, adults on honey, and whitefly diets performed the same over a 21-d experiment. Excluding those on the water diet, survival of beetles on the various diets ranged from ~50-80% after 21 d. In an open choice assay across 7 h, D. catalinae adults were found on the whitefly diet in a much greater incidence than on the other diets, and the number of beetles found on the whitefly diet increased over time. The data supports that when D. catalinae are employed in greenhouses or fields for whitefly management, during low prey populations, honeydew from the whitefly can help sustain the population of this predator. Moreover, a supplemental food such as a honey solution can help sustain the population of D. catalinae when the prey is decreased to low numbers. These results may help in the development of strategies to enhance the utility of predators for the management of whiteflies.

Effects of Body Size, Diet, and Mating on the Fecundity and Longevity of the Goldspotted Oak Borer (Coleoptera: Buprestidae)

“…Longevity was significantly greater when adults were fed a 10% honeywater and Q. kello^ii leaf diet. Sugar-enriched diets are known to increase the fecundity (Benschoter and Leal 1976, Heimpel et al 1997, Baggeu and Gurr 1998, Marchioro and Foerster 2013 and longevity (Benschoter and Leal 1976, Haynes 1985, Fadamiro and Baker 1999, Lauzière et al 2000, Tisdale and Sappington 2001, Simmons et al 2012) of many insects, and are therefore a useful and cost-effective addition to massrearing programs. A. auroguttatus females had an -140-250% increase in average lifetime egg production, an approximate 44-97% increase in total oviposition period (i.e., 21-42 d longer), and lived, on average, =«23-50 d longer (i.e., 27-69% longer) when given an additional carbohydrate resource in the form of 10% honey-water than females that were fed Q. kelloggii leaves and water only.…”

Intra-plant spatial interaction between Delphastus catalinae (Coleoptera: Coccinellidae) and Bemisia tabaci biotype B (Hemiptera: Aleyrodidae) and its effect on predation rates

“…On the 4 th day after predators were released, all the leaves and leaflets of each plant were cut to re-count the number of SWF nymphs on the underside of each leaflet using a dissecting stereomicroscope. We decided on this observation time period because it was sufficient for most of the predators to have either died or reached a plant and found prey, considering that less than 10% of D. catalinae adults survive without food after 4 days (Simmons et al, 2012). Also, a longer observation time would have complicated the distinction between SWF nymphs consumed by predators and those that completed their nymphal stage.…”

Geïntegreerde bestrijding van plagen in de sierteelt onder glas : een systeembenadering met preventieve biologische bestrijding als basis

“…Bij lage dichtheden van wittevlieg kunnen populaties zich niet goed handhaven (Hoelmer et al 1993). Het aanbieden van honingwater kan de levensduur van volwassen kevers verlengen ten opzichte van alleen water, maar de aanwezigheid van wittevlieg verbeterd de overleving aanzienlijk (Simmons et al 2012). Een mogelijke manier om volwassen kevers te laten overwinteren in kassen is het aanbieden van een alternatieve onschadelijke wittevliegsoort op planten, het zogenaamde bankerplantsysteem (Huang et al 2011 De kevers van kaswittevlieg waren heel iets lichter en minder lang dan bij de andere wittevliegsoorten, maar de verschillen waren minimaal en niet significant.…”