Occurrence of insect pests on maize silk and ears and damage evaluation

Abstract

The work was conducted in commercial field corn at the National Corn and Sorghum Research Center, CNPMS-Embrapa in Sete Lagoas, MG, Brazil. Samples were taken from silk and from ears at the milk stage to evaluate the occurrence of insect feeding on ovipositing or making damage to those maize structures. The fall armyworm, Spodoptera frugiperda (J. E. Smith) and the corn earworm, Helicoverpa zea (Boddie) were the predominant species. The larva predominance of one or another species on silk varied according to the sampled field. It was also affected by the intra and interespecific competition, by the plant phenological stage and probably by factors related to the local. The damage observed in mature ears was associated with the infestation in the milk stage. Pseudaletia sequax Franclemont was the third species found on the silk. Species of Coleoptera and Diptera, considered as secondary pests were common on the tip of the ears. Species of Heteroptera were found either on the silk and on the ears.