Efficacy of Fortenza Duo® against fall armyworm Spodoptera frugiperda over time

Fall armyworm (FAW), is one of the most detrimental pests in agriculture, due to its ability to feed on a several important crops, causing substantially decreased yields and significant economic losses.

For many years, FAW management had heavily relied on transgenic plants expressing Bacillus thuringiensis(Bt) traits. However, there are now existing FAW populations exhibiting resistance to Bt, which threatens food security worldwide. In order to mitigate or slow down Bt resistance, insecticidal seed treatment strategies have been implemented with current Bt technology to suppress early season populations.

However, the residuality of FAW control when insecticidal seed treatment is combined with Bt plants and conventional plants is still unclear, as the insecticide residue in plant decreases overtime. To elucidate the control window of FAW by seed treatment and Bt, we performed greenhouse and field trials where Bt corn seeds (Agrisure Viptera) were treated with Fortenza^® (a.i. Cyantraniliprole) an anthranilic diamide. For these trials, Fortenza^® treated and untreated transgenic (Bt) and non-transgenic corn plants were infested with FAW larvae at 7,14, 21 and 28 days after planting. FAW survival and corn foliage damage was recorded 24 and 48 hr after every infestation. By determining the efficacy period of Fortenza^®, FAW management practices can be improved and may also provide insights to manage FAW Bt resistance by adding a secondary mode of action different from Bt, to therefore extend Bt crop durability.