Contrasting Role of Temperature in Structuring Regional Patterns of Invasive and Native Pestilential Stink Bugs

Abundance of Halyomorpha halys (Hemiptera: Pentatomidae) and Megacopta cribraria (Hemiptera: Plataspidae) in Soybean in Areas with Few Previous Sightings in Tennessee

Halyomorpha halys (Stål) and Megacopta cribraria (Fabricius) are two exotic invasive pests that have invaded the United States in recent years. Halyomorpha halys can damage various fruits, vegetables, and field crops, such as soybean and corn, while Megacopta cribraria only attacks soybean and kudzu, a weed species. They are currently found in southeastern states and threaten soybean and other crops grown in the region. This study evaluated the seasonal abundance of H. halys and M. cribraria in soybeans in 2016 and 2017 in two counties in the central region of Tennessee, where both species had either a few sightings or none that were recorded when this research was being planned. Lures and sweep sampling were used to monitor H. halys, and sweep sampling was used to monitor M. cribraria. Halyomorpha halys was first detected in samples in late July. Their numbers increased in early to mid-September, reached the economic threshold in late Sept, and then started to decline. Megacopta cribraria was first detected in mid to late July, increased their populations in September, but did not reach the economic threshold and declined mid-October. Our results showed the seasonal abundances of H. halys and M. cribraria and their establishment in the central region of Tennessee.

Improving invasive species management using predictive phenology models: an example from brown marmorated stink bug (Halyomorpha halys) in Japan

BACKGROUND

In order to better understand the population dynamics of invasive species in their native range, we developed two predictive phenological models using the ubiquitous invasive insect pest, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), as the model organism. Our work establishes a zero-inflated negative binomial regression (ZINB) model, and a general additive mixed model (GAMM) based on 11 years of black light trap monitoring of H. halys at three locations in Japan.

RESULTS

The ZINB model indicated that degree days (DD) have a significant effect on the trap catch of adult H. halys, and that precipitation has no effect. A dataset generated by 1000 simulations from the ZINB suggested that higher predicted trap catches equated to a lower probability of encountering a zero-count. The GAMM produced a cubic regression smooth curve which forecasts the seasonal phenology of H. halys as following a bell-shaped trend in Japan. Critical DD points during the field season in Japan included 261 DD for first H. halys adult detection and 1091 DD for peak activity.

CONCLUSIONS

This study establishes the first models capable of forecasting native H. halys population dynamics based on DD. These robust models practically improve population forecasting of H. halys in the future and help fill gaps in knowledge pertaining to its native phenology, thus ultimately contributing to the progression of efficient management of this globally invasive species. © 2021 Society of Chemical Industry.

Temperature and Humidity Interact to Influence Brown Marmorated Stink Bug (Hemiptera: Pentatomidae), Survival

High-temperature events can influence insect population dynamics and could be especially important for predicting the potential spread and establishment of invasive insects. The interaction between temperature and environmental humidity on insect populations is not well understood but can be a key factor that determines habitat range and population size. The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive agricultural pest in the United States and Europe, which causes serious economic damage to a wide range of crops. This insect's range continues to expand. It has recently invaded the Central Valley of California, which has a hotter and drier climate compared with the Eastern United States where this insect is established. We investigated how high-temperature events and relative humidity would impact the survival and reproduction of H. halys. Using incubators and humidity chambers, we evaluated the impact of humidity and short-term (2 d) high-temperature exposure on the survival and development of H. halys eggs, nymphs, and adults. We found that high temperatures significantly reduced H. halys survival. The impact of humidity on H. halys survival was dependent on temperature and life stage. Low humidity decreased first-instar survival but not third- to fourth-instar survival. High humidity increased first instar survival but decreased third- to fourth-instar survival. Humidity did not influence adult or egg survival. We also found that high temperatures decreased H. halys reproduction. Our findings have important implications for understanding the invasive ecology of H. halys and may be used to improve models predicting H. halys range expansion.

Influence of Temperature on Age-Stage, Two-Sex Life Tables for a Minnesota-Acclimated Population of the Brown Marmorated Stink Bug (Halyomorpha halys)

Temperature is a critical single factor influencing insect population dynamics, and is foundational for improving our understanding of the phenology of invasive species adapting to new agroecosystems or in the process of range expansion. An age-stage, two-sex life table was therefore developed to analyze fundamental demographic features such as development, survival, and reproduction of a Minnesota-acclimated population of the invasive brown marmorated stink bug (Halyomorpha halys), in the north central USA. All salient life history parameters were estimated to better understand the population growth potential of H. halys at the current limit of its northern range in North America. We examined the effect of selected constant temperatures on immature development and survival (15-39 °C), and adult reproduction longevity (17-36 °C) of H. halys in the laboratory. The Minnesota population developed faster and survived at higher rates relative to a population that had previously established in Pennsylvania, USA. Mean generation time for the Minnesota population was minimized at 30 °C, while survival and fecundity were maximized at 27 and 23 °C, respectively. Given these findings, we assessed the effect of temperature on the intrinsic rate of increase (rm), the life table parameter that integrates the effects of temperature on development, survival, and reproduction. A Ratkowsky model predicted rmwas maximized (0.0899) at 27.5 °C. We discuss the implications of our findings for understanding population growth rates for H. halys in the context of a warming climate, and potential to emerge as a serious crop pest in the Midwest U.S. region.

Climate Change Impacts on the Potential Distribution and Abundance of the Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) With Special Reference to North America and Europe

The invasive brown marmorated stink bug, Halyomorpha halys (Stål; Hemiptera: Pentatomidae), has recently emerged as a harmful pest of horticultural crops in North America and Europe. Native to East Asia, this highly polyphagous insect is spreading rapidly worldwide. Climate change will add further complications to managing this species in terms of both geographic distribution and population growth. This study used CLIMEX to compare potential H. halys distribution under recent and future climate models using one emission scenario (A2) with two different global circulation models, CSIRO Mk3.0 and MIROC-H. Simulated changes in seasonal phenology and voltinism were examined. Under the possible future climate scenarios, suitable range in Europe expands northward. In North America, the suitable H. halys range shifts northward into Canada and contracts from its southern temperature range limits in the United States due to increased heat stress. Prolonged periods of warm temperatures resulted in longer H. halys growing seasons. However, future climate scenarios indicated that rising summer temperatures decrease H. halys growth potential compared to recent climatic conditions, which in turn, may reduce mid-summer crop damage. Climate change may increase the number of H. halys generations produced annually, thereby enabling the invasive insect to become multivoltine in the northern latitudes of North America and Europe where it is currently reported to be univoltine. These results indicate prime horticultural production areas in Europe, the northeastern United States, and southeastern Canada are at greatest risk from H. halys under both current and possible future climates.