Comparative study of insecticides for the management of fall armyworm (Spodoptera frugiperda) in maize crop

Maize, also known as Zea mays L., is a crucial staple crop grown globally, used for human consumption, livestock forage, and poultry feed. In Pakistan, it is the third most important cereal crop after wheat and rice. Its demand is increasing due to its diverse usage, but pests and diseases cause yield loss.This study aimed to evaluate the efficacy of five synthetic insecticides (chlorpyrifos, lambda cyhalothrin, carbofuran, momonehypo, and emamectin benzoate) in controlling fall armyworm infestations in maize fields. Field trials were conducted using two different formulations (granular and emulsified concentration) and a control treatment. The insecticides were applied at the recommended dose rate when the population reached the economic threshold level. Data on mortality were collected after 3, 7, and 10 days of post-application. The results showed that the highest mortality rate (74.77%) of fall armyworm was observed in the treatment treated with momonehypo after 10 days of post-application, while the lowest mortality rate (49.46%) was recorded in the treatment treated with emamectin benzoate during the same time intervals. The other insecticides exhibited mortality rates of 67.91%, 64.88%, and 57.52%, following the order of chlorpyrifos, lambda cyhalothrin, and carbofuran, respectively. Therefore, the efficacy order of the insecticides against S. frugiperda was momonehypo > chlorpyrifos > lambda cyhalothrin > carbofuran and emamectin benzoate. Overall, the study demonstrated that synthetic insecticides can significantly control fall armyworm infestations in maize fields for the long term, which is crucial for preserving the maize crop.