Conservation of Ephestia kuehniella eggs as hosts for Trichogramma ostriniae

Abstract

Mass rearing of numerous biological control agents depends on large amounts of factitious hosts like Ephestia kuehniella eggs. Moreover, production of some parasitoids, such as Trichogramma, requires hosts of high quality. The objective of this study was to determine the optimal conservation method that allows E. kuehniella eggs to remain suitable for parasitism and development of Trichogramma ostriniae for the longest period of time. Fifteen sterilization-conservation treatments were compared: nine consisting of submersion of the eggs in liquid nitrogen as a conservation mode, two consisting of sterilization of the eggs with UV and four consisting of sterilization with freezing at À15°C. Liquid nitrogen submersion of E. kuehniella eggs did not allow the production of T. ostriniae. The sterilization by exposition to UV light followed by conservation using vacuum packing and refrigeration at 4°C provided the longest conservation of E. kuehniella eggs for T. ostriniae rearing. It was the only treatment (75.4 AE 4.62%) for which the parasitism rate remained over 70% after 2 weeks.

Bracon wasps for ecological pest control–a laboratory experiment

“…By spinning webbings that clog the machinery in industrial flourmills, E. kuehniella causes economic damages ( Jacob & Cox, 1977 ; Ayvaz & Karabörklü, 2008 ). Eggs or larvae of E. kuehniella are commonly used to rear parasitoids such as Trichogramma or Bracon ( Faal-Mohammad-Ali & Shishehbor, 2013 ; Xu, Wang & He, 2008 ; St-Onge et al, 2015 ).…”

“…Additionally, temperature plays an important role in the developmental biology of Bracon species and also affects the efficacy of parasitization ( Rao & Kumar, 1960 ; Thanavendan & Jeyarani, 2010 ). As agents for biological control, braconid wasps are often used in addition to trichogrammatid parasitoids which parasitize eggs of insect pests ( Brower, 1988 ) which is also done to dam E. kuehniella ( Ayvaz & Karabörklü, 2008 ; St-Onge et al, 2015 ). If high pest pressure occurs and many eggs remain unparasitized and develop to larvae, B. brevicornis and B. hebetor can be used in support.…”

“…Such losses of biodiversity affect ecosystem services; e.g., the loss of pollinator species such as wild bees or bumblebees causes a reduction in pollination (Biesmeijer et al, 2006; Potts economic damages (Jacob & Cox, 1977;Ayvaz & Karabörklü, 2008). Eggs or larvae of E. kuehniella are commonly used to rear parasitoids such as Trichogramma or Bracon (Faal-Mohammad-Ali & Shishehbor, 2013;Xu, Wang & He, 2008;St-Onge et al, 2015).…”

A conserved role of the duplicatedMasculinizergene in sex determination of the Mediterranean flour moth,Ephestia kuehniella

“…It used to be a serious pest of dried food products, in particular flour, but due to improved hygiene regulations, it is no longer considered a major pest [29]. Nowadays, E. kuehniella is widely accepted as a factitious host that is easy to rear in large quantities, and thus its eggs and larvae are used as a food source for a broad range of beneficial arthropods used in biological control [30][31][32].…”

Modeling adult emergence and fecundity of factitious hosts under different food sources supports massive egg production management

“…Despite the economic importance of these insects, they are extensively used in the laboratory production of parasitoids and predators for biological control of a large number of key pests (e.g. Dias-Pini et al, 2014; St-Onge et al , 2016).…”