Advisor(s)
Abstract(s)
A polyclonal antiserum (AS) was developed
and characterized for the detection of immature stages of
the black-scale, Saissetia oleae, in whole body homogenized
field-collected coccinellid species, using an indirect
enzyme-linked immunosorbent assay (ELISA). The indirect
ELISA showed to be sensitive to the S. oleae AS, detecting
a protein content between 0.118 and 0.0374 lg mL-1. The
specificity of the ELISA was tested by assaying a range of
sympatric predators and alternative preys with the S. oleae
AS. Coccinellid larvae obtained the highest cross-reaction
and a positive–negative threshold was established at
0.674 lg mL-1 protein. A total of 1,322 coccinellids were
field-collected in three olive groves located in Tra´s-os-
Montes (northeast of Portugal) by the beating technique and
were analyzed to detect S. oleae proteins in their guts. Fieldcollected
coccinellids which attained a S. oleae protein
concentration equivalent higher than the threshold were considered as a positive reaction. In the overall collected
coccinellids, 21.2% reacted positively with the S. oleae AS.
Chilocorus bipustulatus and coccinellid larvae obtained the
highest percentages of positives with 43.4 and 40.8%,
respectively. The greatest frequency of positive responses
occurred at the beginning of July, mid-August, and mid-
October coinciding with the occurrence of the first, second
and third instar nymphs of S. oleae, respectively. Thus, in
this study, the role of coccinellids as natural control agents
of S. oleae was highlighted by the number of individuals
and species that tested positive for S. oleae AS.
Description
Keywords
Coccinellids ELISA Gut content analysis Polyclonal antiserum Predation Saissetia oleae
Citation
Santos, S. A.; Pereira, J.A.; Rodrigues, C.; Torres, L.M.; Pereira, A.M.N.; Nogueira, A.J.A. (2009). Identification of predator-prey relationships between coccinellids and Saissetia oleae (Hemiptera: Coccidae), in olive groves, using an enzyme-linked immunosorbent assay. Journal of Pest Science. ISSN 1612-4758. 82:2, p. 101-108