Translator Disclaimer
1 April 2009 Spatial Patterns of Parasitism of the Solitary Parasitoid Pseudapanteles dignus (Hymenoptera: Braconidae) on Tuta absoluta (Lepidoptera: Gelechiidae)
Norma E. Sánchez, Patricia C. Pereyra, María G. Luna
Author Affiliations +

We examined the interaction between the tomato leafminer, Tuta absolute (Meyrick) (Lepidoptera: Gelechiidae), a key pest of tomato crops in South America, and its main solitary larval parasitoid, Pseudapanteles dignus (Muesebeck) (Hymenoptera: Braconidae). The pattern of parasitism of T. absolute, by the parasitoid was studied at three scales on tomato crops: plant, leaf, and leaflet. Host density, spatial distributions of both host and parasitoid, percentages of parasitism, variation in the probability and risk of parasitism in relation to host density, and the spatial density dependence were assessed in a horticultural region in Argentina. The spatial distribution of T. absoluta was clumped at all sites and scales, whereas that of P. dignus was much more variable, fitting to negative, positive binomial distributions and to Poisson series. Percentages of parasitism were as follows: site 1,17.06%; site 2,27.53%; site 3,26.47%; site 4,45.95%. Parasitoid aggregation in relation to host density was found at leaf and leaflet scales. However, the proportion of parasitized hosts was independent of host density. The variability of parasitism rates exhibited at the three spatial scales seems to result in partial refuges for the host, which might contribute to the persistence of the interaction between host and parasitoid. We discuss our field observations in relation to ecological theory and its potential application to the biological control of T. absoluta on tomato.

© 2009 Entomological Society of America
Norma E. Sánchez, Patricia C. Pereyra, and María G. Luna "Spatial Patterns of Parasitism of the Solitary Parasitoid Pseudapanteles dignus (Hymenoptera: Braconidae) on Tuta absoluta (Lepidoptera: Gelechiidae)," Environmental Entomology 38(2), 365-374, (1 April 2009).
Received: 11 July 2008; Accepted: 1 December 2008; Published: 1 April 2009

This article is only available to subscribers.
It is not available for individual sale.

Get copyright permission
Back to Top