Biocontrol Science and Technology (2022) 32, 497-510

Sahadatou Mama Sambo, Shepard Ndlela, Hannalene du Plessis, Francis Obala and Samira Abuelgasim Mohamed (2022)
Ratio dependence effects of the parasitoid Dolichogenidea gelechiidivoris on its associated host Tuta absoluta
Biocontrol Science and Technology 32 (4), 497-510
Abstract: The invasion of Africa by the South American leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) has caused a severe threat to the production of tomato, Solanum lycopersicum L. (Solanaceae) crops. The excessive use of pesticides for controlling this pest has increased, together with the associated environmental and human health risks. The parasitoid, Dolichogenedia gelechiidivoris Marsh. (Hymenoptera: Braconidae), has been imported into Africa for classical biological control of T. absoluta. To facilitate the mass production of the parasitoid and to predict the success under field conditions, its performance under laboratory conditions was investigated at five densities of T. absoluta larvae, viz. 20, 50, 100, 150, and 200 offered to either a single or group of mated parasitoid females. The findings revealed that D. gelechiidivoris exhibited a type II functional response. Host and parasitoid densities affected superparasitism, which was generally low, less than 5%. Parasitoid offspring emergence ranged from 8 to 39 wasps for a single foraging female, and 6-59 wasps, for a group of foraging females. The host larval densities did not affect the male: female ratio. This study showed that D. gelechiidivoris acts in a density-dependent manner. Therefore, for optimisation of the mass production of the parasitoid, the maximum number of hosts should be offered to a female. The results suggest that D. gelechiidivoris could be effective for classical biological control of T. absoluta, albeit field evaluation is required to validate this finding.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
rearing/culturing/mass production
classical biocontrol/new introduction

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Phthorimaea absoluta
Apanteles gelechiidivoris (parasitoid)	Phthorimaea absoluta