Comparative biology of Euschistus heros (F.) (Hemiptera: Pentatomidae) feeding on cotton and soybean reproductive structures.

The neotropical brown stink bug, Euschistus heros (F.), is a phytophagous pentatomid that causes considerable economic losses in soybean crop, but it has been recently reported using cotton as a new host plant. Nymphs and adults of E. heros were raised on six different food sources composed of the reproductive structures of cotton and soybean plants: a standard diet (green-bean pods + raw peanuts + privet fruits), soybean seeds, soybean pods, cotton seeds, cotton bolls, and cotton floral buds. The following biological parameters were evaluated: nymph developmental time, instar duration, and survivorship; adult weight at emergence; male and female longevity; duration of pre-oviposition and oviposition periods; and female fecundity and fertility. Nymphal development time and survival, as well as the adult weight and fecundity of E. heros fed on cotton bolls and seeds were reduced if compared to those fed on soybean pods. The cotton floral buds did not support the immature development nor the reproduction of adults of E. heros. Most of the cotton plant structures fed to E. heros caused high nymph mortality and low adult fertility. Cotton, therefore, appeared to be an unsuitable host for the development and reproduction of E. heros. Therefore, our data may allow us to suggest that the occurrence of E. heros on cotton may be due to occasional dispersion in search for shelter.