Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae)

The amaranth leaf-webber, Spoladea recurvalis (Fabricius; Lepidoptera: Crambidae), is a serious pest of Amaranthus sp. in Africa and Asia. Apanteles hemara (Nixon; Hymenoptera: Braconidae) is by far the most important larval endoparasitoid of the amaranth leaf-webber. We examined the effects of host...

Full description

Bibliographic Details
Main Authors: Othim, S.T.O., Ramasamy, S., Kahuthia-Gathu, R., Dubois, T., Ekesi, S., Fiaboe, K.K.M.
Format: Journal Article
Language:Inglés
Published: Oxford University Press 2019
Subjects:
Online Access:https://hdl.handle.net/10568/102159
_version_ 1855519732227112960
author Othim, S.T.O.
Ramasamy, S.
Kahuthia-Gathu, R.
Dubois, T.
Ekesi, S.
Fiaboe, K.K.M.
author_browse Dubois, T.
Ekesi, S.
Fiaboe, K.K.M.
Kahuthia-Gathu, R.
Othim, S.T.O.
Ramasamy, S.
author_facet Othim, S.T.O.
Ramasamy, S.
Kahuthia-Gathu, R.
Dubois, T.
Ekesi, S.
Fiaboe, K.K.M.
author_sort Othim, S.T.O.
collection Repository of Agricultural Research Outputs (CGSpace)
description The amaranth leaf-webber, Spoladea recurvalis (Fabricius; Lepidoptera: Crambidae), is a serious pest of Amaranthus sp. in Africa and Asia. Apanteles hemara (Nixon; Hymenoptera: Braconidae) is by far the most important larval endoparasitoid of the amaranth leaf-webber. We examined the effects of host density and age on the biological characteristics of A. hemara. The regression model of the number of hosts supplied to A. hemara against the number of larvae parasitized resulted in a curve corresponding to type II functional response, with a significant increase in the number of hosts parasitized up to the density of 30 hosts before being constant up to 40 hosts. In contrast, the parasitism rate decreased linearly with increasing host densities. Development time, sex ratio, and adult longevity were not significantly affected by host density. The immature parasitoid mortality was significantly higher at higher host densities. Apanteles hemara did not parasitize 7-d-old larvae and beyond, while parasitism was significantly higher among 1- to 2-d-old compared with 3- to 4-d-old larvae. Immature parasitoid mortality was 2.6 times higher in 1- to 2-d-old larvae compared with 5- to 6-d-old larvae. The developmental period of the parasitoid from egg to adult was longest among 1- to 2-d-old larvae and least among 5- to 6-d-old larvae. Nonreproductive mortality was markedly higher among 1- to 2-d-old larvae compared with the older larvae. Adult female A. hemara were significantly larger on 3- to 4-d-old larvae compared with either 1- to 2-d-old or 5- to 6-d-old larvae. We discuss the implications of our results for the interpretation of functional response in parasitoids, mass rearing, conservation, and augmentative biological control of S. recurvalis.
format Journal Article
id CGSpace102159
institution CGIAR Consortium
language Inglés
publishDate 2019
publishDateRange 2019
publishDateSort 2019
publisher Oxford University Press
publisherStr Oxford University Press
record_format dspace
spelling CGSpace1021592024-05-01T08:16:07Z Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae) Othim, S.T.O. Ramasamy, S. Kahuthia-Gathu, R. Dubois, T. Ekesi, S. Fiaboe, K.K.M. biological control parasitism mortality seed figure apanteles larvae ecology The amaranth leaf-webber, Spoladea recurvalis (Fabricius; Lepidoptera: Crambidae), is a serious pest of Amaranthus sp. in Africa and Asia. Apanteles hemara (Nixon; Hymenoptera: Braconidae) is by far the most important larval endoparasitoid of the amaranth leaf-webber. We examined the effects of host density and age on the biological characteristics of A. hemara. The regression model of the number of hosts supplied to A. hemara against the number of larvae parasitized resulted in a curve corresponding to type II functional response, with a significant increase in the number of hosts parasitized up to the density of 30 hosts before being constant up to 40 hosts. In contrast, the parasitism rate decreased linearly with increasing host densities. Development time, sex ratio, and adult longevity were not significantly affected by host density. The immature parasitoid mortality was significantly higher at higher host densities. Apanteles hemara did not parasitize 7-d-old larvae and beyond, while parasitism was significantly higher among 1- to 2-d-old compared with 3- to 4-d-old larvae. Immature parasitoid mortality was 2.6 times higher in 1- to 2-d-old larvae compared with 5- to 6-d-old larvae. The developmental period of the parasitoid from egg to adult was longest among 1- to 2-d-old larvae and least among 5- to 6-d-old larvae. Nonreproductive mortality was markedly higher among 1- to 2-d-old larvae compared with the older larvae. Adult female A. hemara were significantly larger on 3- to 4-d-old larvae compared with either 1- to 2-d-old or 5- to 6-d-old larvae. We discuss the implications of our results for the interpretation of functional response in parasitoids, mass rearing, conservation, and augmentative biological control of S. recurvalis. 2019-09-23 2019-07-11T11:54:10Z 2019-07-11T11:54:10Z Journal Article https://hdl.handle.net/10568/102159 en Limited Access Oxford University Press Othim, S.T.O., Ramasamy, S., Kahuthia-Gathu, R., Dubois, T., Ekesi, S. & Fiaboe, K. (2019). Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae). Journal of Economic Entomology, 1-11.
spellingShingle biological control
parasitism
mortality
seed figure
apanteles
larvae
ecology
Othim, S.T.O.
Ramasamy, S.
Kahuthia-Gathu, R.
Dubois, T.
Ekesi, S.
Fiaboe, K.K.M.
Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae)
title Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae)
title_full Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae)
title_fullStr Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae)
title_full_unstemmed Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae)
title_short Effects of host age and density on the performance of Apanteles hemara (Hymenoptera: Braconidae), a larval endoparasitoid of Spoladea recurvalis (Lepidoptera: Crambidae)
title_sort effects of host age and density on the performance of apanteles hemara hymenoptera braconidae a larval endoparasitoid of spoladea recurvalis lepidoptera crambidae
topic biological control
parasitism
mortality
seed figure
apanteles
larvae
ecology
url https://hdl.handle.net/10568/102159
work_keys_str_mv AT othimsto effectsofhostageanddensityontheperformanceofapanteleshemarahymenopterabraconidaealarvalendoparasitoidofspoladearecurvalislepidopteracrambidae
AT ramasamys effectsofhostageanddensityontheperformanceofapanteleshemarahymenopterabraconidaealarvalendoparasitoidofspoladearecurvalislepidopteracrambidae
AT kahuthiagathur effectsofhostageanddensityontheperformanceofapanteleshemarahymenopterabraconidaealarvalendoparasitoidofspoladearecurvalislepidopteracrambidae
AT duboist effectsofhostageanddensityontheperformanceofapanteleshemarahymenopterabraconidaealarvalendoparasitoidofspoladearecurvalislepidopteracrambidae
AT ekesis effectsofhostageanddensityontheperformanceofapanteleshemarahymenopterabraconidaealarvalendoparasitoidofspoladearecurvalislepidopteracrambidae
AT fiaboekkm effectsofhostageanddensityontheperformanceofapanteleshemarahymenopterabraconidaealarvalendoparasitoidofspoladearecurvalislepidopteracrambidae