What Happened to Nezara viridula (L.) in the Americas? Possible Reasons to Explain Populations Decline

Abstract

Once abundant in the Americas, the southern green stink bug Nezara viridula (L.) has gradually declined in numbers. Until the 1990s, it was considered the main pest of major crops such as soybean, Glycine max (L.) Merrill, particularly in southern Brazil and southern USA, as well as Argentina, Uruguay, and other countries. In the past 15+ years, a dramatic population decrease was observed to the point of now being considered a secondary pest in these referred countries. In this article, we list and discuss possible reasons which explain the decline in N. viridula population in the Americas. These factors include the following: (1) the steady increase of herbicides used in no-tillage/multiple cropping systems affecting potential hosts such as weeds in crop fields and nearby natural vegetation; (2) the change in cultivation systems, mostly in the Neotropics, favoring other species more adapted to exploit crops in modern day agriculture; (3) competition among several species of stink bugs that colonize major crops; (4) the growing impact of several species of egg parasitoids, some of them laboratory reared and released in crop fields, and other natural enemies (parasitoids and predators); and (5) the impact of global climate change affecting its distribution and biology.

Prevalence, damage, management and insecticide resistance of stink bug populations (Hemiptera: Pentatomidae) in commodity crops

“…Among them, adaptability of these insect pests to soybean as a result of the availability of large areas with this host plant (Panizzi & Corrêa‐Ferreira, ; Husch et al ., ), global climate changes that favour species adapted to warmer conditions (Robinet & Roques, ; Saluso et al ., ), multiple cropping systems that affect host weeds (Smaniotto & Panizzi, ), inter‐specific competition among pentatomids, competitive release of nontarget pest outbreaks (stink bug populations) associated with Bt‐crops (Zeilinger et al ., ) and indeterminate soybean genotypes with longer pod filling stages. In addition, not adopting tillage practices may have mainly favoured Dichelops species that require sheltered conditions under crop stubble (Panizzi, ; Panizzi & Lucini, ).…”

Non‐targeted insecticidal stress in a pest species: insecticides, sexual fitness and hormesis in the Neotropical brown stink bug Euschistus heros

“…Examination of insecticidal stress on non‐targeted pest species is lacking, despite its potential practical management consequences (Ripper, ; Hardin et al ., ; Guedes & Cutler, ). We therefore explored effects of insecticides used in soybean for controlling caterpillars and whiteflies on the mating behaviour and sexual fitness of the Neotropical brown stink bug, a pest of increasing status in Argentina and Brazil (Panizzi, ; Bueno et al ., ; Panizzi & Lucini, ; Tuelher et al ., ).…”

Review: classical biological control of invasive stink bugs with egg parasitoids – what does success look like?

“…soybean), tree nuts and a number of other crops throughout the world . Thought to have originated in Ethiopia, N. viridula rapidly expanded its geographical range throughout the world and became a cosmopolitan pest over the course of the 20th Century . The most common and closely associated parasitoid of N. viridula throughout most of its range is Trissolcus basalis (Hymenoptera: Scelionidae) .…”

“…In Australia, New Zealand and Hawaii, T. basalis spread rapidly, high parasitism rates were recorded, and the biological control program was declared by some to be a complete success and a landmark case of classical biological control . Trissolcus basalis also spread rapidly in South America, became an important part of pest management programs against N. viridula and other pest pentatomids in soybean, and reportedly was used with some success in inoculative biological control programs . Trissolcus basalis currently parasitizes N. viridula in Europe and Japan, although it was not intentionally introduced to these regions …”