Assessment of grain yield losses in pearl millet due to the millet stemborer, Coniesta ignefusalis (Hampson)

Abstract

Studies were conducted at the ICRISAT Sahelian Centre, Niger, to assess damage and yield loss by the millet stemborer, Coniesta ignefusalis (Lepidoptera: Pyralidae) on Pennisetum glaucum (L.) R. Brown. Although 78% of stems were infested, late attack by the millet stemborer on millet plants resulted in bored stems yielding more than unbored ones. Artificial infestations with 5 and 10 larvae per plant at 2 weeks after plant emergence (WAE) resulted in 50 to 70% plants with deadhearts and 24 to 100% avoidable yield loss. At 4 weeks after plant emergence, infestations with 5 larvae and 10 larvae per plant resulted in 7% increase in yield and 16% yield loss, respectively. Therefore, both the age of plant and density of borer population at the time of infestation can influence resulting stemborer damage and yield loss on pearl millet. © 2003 ICIPE.