Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratory

We tested the functional response of the phytoseiid predator Phytoseiulus macropilis (Banks, 1904) to different population densities of Tetranychus urticae Koch, 1836 (the two-spotted spider mite - TSSM) in the laboratory. We evaluated the curve that best fits the data obtained, based on the reduced...

Full description

Bibliographic Details
Main Authors: Noeli Juarez Ferla, Marla Marchetti, Liana Johann, Claus Haetinger
Format: Article
Language:English
Published: Sociedade Brasileira de Zoologia 2011-02-01
Series:Zoologia (Curitiba)
Subjects:
Online Access:http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000100003
_version_ 1797967617135214592
author Noeli Juarez Ferla
Marla Marchetti
Liana Johann
Claus Haetinger
author_facet Noeli Juarez Ferla
Marla Marchetti
Liana Johann
Claus Haetinger
author_sort Noeli Juarez Ferla
collection DOAJ
description We tested the functional response of the phytoseiid predator Phytoseiulus macropilis (Banks, 1904) to different population densities of Tetranychus urticae Koch, 1836 (the two-spotted spider mite - TSSM) in the laboratory. We evaluated the curve that best fits the data obtained, based on the reduced X². The predators were obtained from leaves of Oso Grande strawberries at the municipality of Bom Princípio, state of Rio Grande do Sul, Brazil. Fifteen seemingly healthy females of P. macropilis were randomly chosen and individualized in each of the arenas with different TSSM densities. The following prey densities were tested: 1, 2, 3, 5, 10, 20, 30, 35, 45, 55, 70 and 125 females. The tests were performed in a germination chamber with photoperiod of 12 hours at 28 ± 1ºC per day and 22 ± 1ºC at night and 80 ± 5% relative humidity. In all tests with up to three prey items, P. macropilis showed low functional response, whereas higher rates were observed when more prey items were offered. There was a strong positive correlation between increased prey numbers and daily prey consumption (r = 0.84 and p = 0.0006). A significant correlation was found between prey consumption and total oviposition (r = 0.70, p = 0.01). The daily oviposition rate was lower when few prey items were offered, increasing significantly with increased prey availability. The results showed a positive correlation between the number of prey items offered to the predator and its oviposition rate (r = 0.66, p = 0.01). Nevertheless, a strong correlation was observed between the daily consumption of prey and eggs/female/day (r = 0.92, p < 0.0001). A shorter oviposition period was reported when up to three prey items were offered. The oviposition period and the increase in prey numbers were positively correlated (r = 0.30, p = 0.34), but the difference was not statistically significant. Nevertheless, the longer the egg-laying period, the greater the oviposition rate (r = 0.90, p < 0.0001). The curve that best fits the data obtained in each case was also calculated, based on the least square method.
first_indexed 2024-04-11T02:34:03Z
format Article
id doaj.art-f9eb8e8d6ef64d1083ee305db82c3b49
institution Directory Open Access Journal
issn 1984-4670
1984-4689
language English
last_indexed 2024-04-11T02:34:03Z
publishDate 2011-02-01
publisher Sociedade Brasileira de Zoologia
record_format Article
series Zoologia (Curitiba)
spelling doaj.art-f9eb8e8d6ef64d1083ee305db82c3b492023-01-02T20:51:32ZengSociedade Brasileira de ZoologiaZoologia (Curitiba)1984-46701984-46892011-02-01281172210.1590/S1984-46702011000100003Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratoryNoeli Juarez FerlaMarla MarchettiLiana JohannClaus HaetingerWe tested the functional response of the phytoseiid predator Phytoseiulus macropilis (Banks, 1904) to different population densities of Tetranychus urticae Koch, 1836 (the two-spotted spider mite - TSSM) in the laboratory. We evaluated the curve that best fits the data obtained, based on the reduced X². The predators were obtained from leaves of Oso Grande strawberries at the municipality of Bom Princípio, state of Rio Grande do Sul, Brazil. Fifteen seemingly healthy females of P. macropilis were randomly chosen and individualized in each of the arenas with different TSSM densities. The following prey densities were tested: 1, 2, 3, 5, 10, 20, 30, 35, 45, 55, 70 and 125 females. The tests were performed in a germination chamber with photoperiod of 12 hours at 28 ± 1ºC per day and 22 ± 1ºC at night and 80 ± 5% relative humidity. In all tests with up to three prey items, P. macropilis showed low functional response, whereas higher rates were observed when more prey items were offered. There was a strong positive correlation between increased prey numbers and daily prey consumption (r = 0.84 and p = 0.0006). A significant correlation was found between prey consumption and total oviposition (r = 0.70, p = 0.01). The daily oviposition rate was lower when few prey items were offered, increasing significantly with increased prey availability. The results showed a positive correlation between the number of prey items offered to the predator and its oviposition rate (r = 0.66, p = 0.01). Nevertheless, a strong correlation was observed between the daily consumption of prey and eggs/female/day (r = 0.92, p < 0.0001). A shorter oviposition period was reported when up to three prey items were offered. The oviposition period and the increase in prey numbers were positively correlated (r = 0.30, p = 0.34), but the difference was not statistically significant. Nevertheless, the longer the egg-laying period, the greater the oviposition rate (r = 0.90, p < 0.0001). The curve that best fits the data obtained in each case was also calculated, based on the least square method.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000100003Biological controlbioecologystrawberrytwo-spotted spider mitecurve adjust
spellingShingle Noeli Juarez Ferla
Marla Marchetti
Liana Johann
Claus Haetinger
Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratory
Zoologia (Curitiba)
Biological control
bioecology
strawberry
two-spotted spider mite
curve adjust
title Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratory
title_full Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratory
title_fullStr Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratory
title_full_unstemmed Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratory
title_short Functional response of Phytoseiulus macropilis under different Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) population density in laboratory
title_sort functional response of phytoseiulus macropilis under different tetranychus urticae acari phytoseiidae tetranychidae population density in laboratory
topic Biological control
bioecology
strawberry
two-spotted spider mite
curve adjust
url http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000100003
work_keys_str_mv AT noelijuarezferla functionalresponseofphytoseiulusmacropilisunderdifferenttetranychusurticaeacariphytoseiidaetetranychidaepopulationdensityinlaboratory
AT marlamarchetti functionalresponseofphytoseiulusmacropilisunderdifferenttetranychusurticaeacariphytoseiidaetetranychidaepopulationdensityinlaboratory
AT lianajohann functionalresponseofphytoseiulusmacropilisunderdifferenttetranychusurticaeacariphytoseiidaetetranychidaepopulationdensityinlaboratory
AT claushaetinger functionalresponseofphytoseiulusmacropilisunderdifferenttetranychusurticaeacariphytoseiidaetetranychidaepopulationdensityinlaboratory