Fall armyworm (S. frugiperda) an Emerging Risk for the Expansion of Maize in the Coastal Zone of Bangladesh: A Survey of Farmers’ Perception and Practices

Maize is being promoted as a new Rabi season crop for the coastal zone in Bangladesh, but the spread of fall armyworm (Spodoptera frugiperda) is an emergent threat that needs to be managed. The prevalence of fall armyworm was surveyed in Patuakhali (Kalaparaupzilla), Barguna (Amtaliupzilla) and Khulna (Dacope and Batiaghataupazilla) districts in coastal Bangladesh using a structured questionnaire and supplemented by a survey of farmer’s awareness of this pest and their current management responses. Adult populations were monitored using pheromone traps and larval populations were counted by sampling maize plants from production fields during October 2019 to April 2020. Of the 120 maize growers, 74% had >10 years farming experience but most were illiterate. They mainly cultivated hybrid maize varieties Miracle, NK40 and BARI hybrid maize-16. All the respondents opined that different stages of maize plants were infested by fall armyworm from seedling stage. The infestation level of fall armyworm increased during February to March and they sprayed chemical insecticides 2-3 times for the management of this pest.  Most of the farmers got pest management information from a pesticide retailer. The number of captured moths in pheromone traps gradually increased from December to March at each coastal district. Larvae of S. frugiperda was first observed on the 1st week of January when temperature was low and reached a peak during the 3rd week of March. Increases in maximum temperature and minimum temperature had positive associations with incidence of larvae whereas increasing relative humidity and rainfall exhibited a negative association. In conclusion, maize growers are familiar with S. frugiperda and they used chemical insecticides for the management of this pest. S. frugiperda control measures need to target the period from January and February.