Data/hora: 08/06/2024 20:49:03

Biblioteca(s): | Embrapa Florestas.
Data corrente: | 03/10/2008
Data da última atualização: | 10/08/2020
Autoria: | LÓPEZ, M. G.; SALMON, S.; NOVO, M.
Título: | Atraction of several species of Collembola to the excreta of two different earthworms: Hormogaster elisae and Aporrectodea giardi.
Ano de publicação: | 2008
Fonte/Imprenta: | In: INTERNATIONAL COLLOQUIUM ON SOIL ZOOLOGY, 15; INTERNATIONAL COLLOQUIUM ON APTERYGOTA, 12., 2008, Curitiba. Biodiversity, conservation and sustainabele management of soil animal: abstracts. Colombo: Embrapa Florestas. Editors: George Gardner Brown; Klaus Dieter Sautter; Renato Marques; Amarildo Pasini. 1 CD-ROM.
Idioma: | Inglês

Conteúdo:

Several studies reported that density and variety of microarthropods are greater in soils with
higher numbers of earthworms (Hamilton and Silman, 1989; Loranger, et al, 1998; Salmon et
al., 1999) while other observations reported a negative impact of earthworms on the density of
microarthropods (McLean and Parkinson, 2000; Migge, 2001; Gutiérrez et al, 2003;).
In order to understand the role of earthworms in the composition and density of Collembola
communities, further experimental studies dissecting the different impacts of earthworms were
performed (Salmon 2001, 2004; Salmon and Ponge, 2001). They demonstrated that earthworms
and earthworm excreta (mixture of mucus and urine) attract a collembolan species, Heteromurus
nitidus .
The objective of the present study was to test the attraction of several collembolan species
(from different families) to the earthworms Aporrectodea giardi (previously proved to positively
influence the densities of one collembolan species, Salmon et al, 2005) and Hormogaster elisae
(previously proved to decrease the microarthropod densities, Gutiérrez et al, 2003). We assessed
whether the excreta of two earthworms species are repulsive or attractant, testing whether (1) A.
giardi may impact Collembola issued from the same habitat, not only at species level but at the
scale of community, and (2) the negative impact of H. elisae on microarthropod densities may
be explained by the behaviour of Collembola subjected to its excreta.
The experiment was performed in six Petri dishes (8 cm diameter) containing two half-disks (5
cm diameter) of filter paper placed at 1.5 cm distance one from each other. One of the half disk
contained earthworm excreta (casts or mucus and urine) and the other was a control (natural
soil aggregates or water, respectively). Casts were obtained from earthworms kept in Petri
dishes on a moistened filter paper during 3 days. Mucus and urine were obtained from earthworms
(that had previously emptied their digestive tube during 3 days) in Petri dishes with half disks of
filter paper during 4 hours. Ten adult Collembola were introduced half-way between the two halfdisks
in each Petri dish. Their abundance was counted on each half-disk every 10 min for 140
min. The experiment was performed at ambient temperature (around 20ºC) and under
homogeneous light conditions. Means of 14 time-countings of Collembola number on each halfdisk
were calculated and compared by a paired t-test.
H. nitidus (Entomobryidae) seems not to be attracted nor to the cast nor to the mucus and urine
from H. elisae, despite this specie had been previously seen to be attracted to the mucus and
urine from A. giardi (Salmon and Ponge, 2001).
Onychiurus pseudogranulosus (Onychiuridae) was only attracted to casts from H. elisae. It is
known that usually species from the Onychiuridae family lives in the deep layer of the soil, so
they could feed on casts from H. elisae as it is an endogeic earthworm.
Another Onychiuridae species Onychiurus sp.2, was attracted to the mucus and urine from A.
giardi and from H. elisae, but not to casts from any of the earthworms.
Biodiversity, Conservation and
Sustainable Management of Soil Animals
August 25 - 29, 2008
Positivo University
Curitiba - Paraná - Brazil
Arrhopalites caecus (Sminthuridae) was attracted to mucus and urine from A. giardi and also to
casts from H. elisae.
F. candida (Isotomidae) was not attracted nor to the casts nor to the mucus and urine from any
earthworm species (H. elisae or A. giardi).
It seems therefore that different earthworm species may impact several collembolan species in
different ways, as different reactions to the attraction test with the excreta from this two earthworm
species were observed.

Palavras-Chave: | Earthworm.
Thesagro: | Minhoca.
Categoria do assunto: | --
Registro original: | Embrapa Florestas (CNPF)
Exemplares: | CNPF - (43798-1) - UPE - PL - -- - CD0305 -  -  - DIS