Releasing number of Telenomus remus (Nixon) (Hymenoptera: Platygastridae) against Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) in corn, cotton and soybean

Abstract

Telenomus remus releasing numbers may vary depending on the crop, plant architecture and/or the plant phenological stage. Thus, we examined the number of parasitoids needed for effective pest control of Spodoptera frugiperda on corn, cotton and soybean. In all crops, the parasitism response in relation to increasing numbers of the parasitoids had a quadratic effect. In corn, the maximum parasitism observed was 99.8% and 96.8% at a parasitoid releasing number of 0.231 and 0.264 T. remus females per S. frugiperda egg at phenological stages V4 and V10, respectively. Differently, in cotton and soybean, the highest parasitim were recorded using the highest tested T. remus releasing numbers (0.297 parasitoid per S. frugiperda egg). In cotton, it was 77.8% and 73.1% at the vegetative and reproductive stages, respectively and in soybean, it was 77.3% and 54.4% also at the vegetative and reproductive stages. Thus, the appropriated T. remus releasing number might vary accordingly to the crop and plant phenological stage, being higher for soybean and cotton and lower for corn.

Timing of releases of the parasitoid Habrobracon hebetor and numbers needed in augmentative biological control against the millet head miner Heliocheilus albipunctella

“…Therefore, it will obviously be much easier to use the millet phenology stage as reference for releases of parasitoids. Using plant phenology stages has also been suggested for releases of the parasitoid Telenomus remus (Nixon) (Hymenoptera: Platygastridae) against fall armyworm in maize, cotton and soybean in Brazil (Pomari et al 2013). Given that farmers usually have different planting dates and use different varieties of different flowering time, the releases of parasitoids will require some coordination among farmers.…”

“…(Hymenoptera: Trichogrammatidae)-several hundred thousand per hectare-against corn borer in maize (Bigler 1986;Wang et al 2014), or augmentative releases of Diachasmimorpha longicaudata Ashmead (Hymenoptera: Braconidae)-20 to 60 thousand per hectare-against Tephritidae fruit flies in orchards (Sivinski et al 1996;Montoya et al 2000). However, differences could be due to the nature of the parasitoid species; the pest cycle; the architecture of the crop plant, and the environment (Thorpe 1985; Cloyd and Sadof 2000;Pomari et al 2013).…”

Relevance of a new scientific publication (Bortolotto et al., 2014) on previous EFSA GMO Panel conclusions on the environmental risk assessment of GM soybean events

“…The egg parasitoid T. remus is considered a potential candidate species for biological control of Spodoptera spp. in the frame of integrated pest management (IPM) programs (e.g., Bueno et al, 2010;Pomari et al, 2013).…”

Telenomus remus (Hymenoptera: Platygastridae) Parasitism on Eggs of Anticarsia gemmatalis (Lepidoptera: Eribidae) Compared With Its Natural Host Spodoptera frugiperda (Lepidoptera: Noctuidae)

“…in superposed layers, even parasitizing eggs lo cated in the inner layers of the egg mass , Bueno et al 2008), a property rarely ob served with other egg parasitoids. In addition, T. remus has high dispersal and host search capacities (Pomari et al 2013), underlining its potential for augmentative biological control programs.…”

“…This parasitoid species has also been thoroughly studied in Brazil (Bueno et al 2008Pomari et al 2012Pomari et al ,2013 for use in soybean IPM. Relatively common soybean pests are Spodoptera cosmioicles (Walker, 1858) and Spodoptera eridania (Cramer, 1782;Lepidoptera: Noctuidae), occurring usually at the beginning of the crop reproductive stage when in addition to feeding on leaves, they also attack the pods (Santos et al 2005;Bueno et al 2008Bueno et al , 2010.…”