Naslov
Population trend and natural enemies of Dialeurodes citri (Homoptera: Aleyrodidae) in Split Region, Croatia

Autori
Žanić, Katja ; Kačić, Sonja ; Katalinić, Miro

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
European Whitefly Symposium, Ragusa 27th -3rd March 2001, Program and Abstract / Bedford, Ian - Ragusa : University of Catania - Faculty of Agriculture, 2001, 38, br.211-P

Skup
1st European Whitefly Symposium

Mjesto i datum
Ragusa, Italija, 27.02.2001. - 03.03.2001

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
citrus whitefly; population dynamic; parasitoid; predators

Sažetak
The flight dynamics of Dialeurodes citri and the population dynamic of preimaginal stages were investigated in Split region from May 1996 to May 1998. Samples of 30 leaves (10 leaves of either lemon, mandarine or persimmon) were collected weekly during the warm periods of the year and once per month during the winter. The number of eggs, larvae (L1, L2, L3, L4) and pupae on all leaves were counted under the stereomicroscope and converted into the number of these per 200 cm2. Our aim was to establish when young larval stages would be present to target appropriate control. Numbers of adult whiteflies were also recorded in orchards on a sample of 100 leaves. Furthermore field and laboratory investigations were conducted on potential natural enemies of Dialeurodes citri in the Split region. The citrus whitefly had three generations per year on citrus and two on the deciduous persimmon. The appearance of adults followed the appearance of young vegetation growth. All development stages had three population peaks on citrus and two on persimmon during vegetation period. The presence of young larval stages (L1, L2) was pronounced during the middle of June, August and October. On persimmon, the population density of the first generation was higher than the second generation. The presence of the endoparasitic wasp Encarsia lahorensis was recorded in orchards, but no predatory activity of lady bugs (Coccinellidae) was observed.. Laboratory studies confirmed the predatory nature of the chrysopid species Chrysoperla carnea, Chrysopa pallens, Dychochrysa flavifrons and Cuntochrysa baetica on D. citri larvae. Furthermore, we observed that spider webs on citrus trees were excellent traps for whitefly adults and preimaginal development was retarded on leaves infested by the citrus leafminer Phyllocnistis citrella.

Izvorni jezik
Engleski

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