Effect of exclusion net timing of deployment and color on Halyomorpha halys (Hemiptera: Pentatomidae) infestation in pear and apple orchards

The brown marmorated stink bug, Halyomorpha halys (Stål, 1855) (Hemiptera: Pentatomidae), is an invasive pest species native to East Asia that has become the major pest for many crops, causing serious economic damage. The occurrence of this invasive pest leads to an increase in broad-spectrum insecticides applications, often with limited results in H. halys management. Exclusion netting based on insect-proof nets is considered an environmentally friendly tactic that may potentially reduce H. halys infestation and damage. In a first experiment, during two growing seasons we investigated whether the timing of exclusion netting deployment affected season-long H. halys infestation and impact on apple and pear production. A second experiment considered the effect of netting color. Our results confirm that insect-proof nettings are effective in controlling H. halys infestations in fruit orchards, also observing an effect of timing of netting deployment on H. halys adult infestation, especially in apple orchards. Netting deployment could be delayed until the growing fruit phase on pear orchards, while on apple orchards it should be performed at flower fading phase. Brown marmorated stink bug infestation and damage were also influenced by the netting color, with black nets having higher infestation levels and fruit damage than white ones. Within an integrated pest management framework, early net deployment and the use of clear color nettings should be considered to reduce H. halys infestation and its damage in pome fruit crops.