A review on temperature and humidity effects onDrosophila suzukiipopulation dynamics

Abstract

Drosophila suzukii is an invasive polyphagous pest of wild and cultivated soft‐skinned fruits, which can cause widespread economic damage in orchards and vineyards. The simulation and prediction of D. suzukii's population dynamics would be helpful for guiding pest management. Therefore, we reviewed and summarized the current knowledge on effects of air temperature and relative humidity on different life cycle parameters of D. suzukii. The literature summary presented shows that high oviposition rates can occur between 18 and 30 °C. Temperatures between 16 and 25 °C resulted in fast and high egg‐to‐adult development success of more than 80%. Oviposition and adult life span were positively affected by high relative humidity; however, the factor humidity is so far rarely investigated. We assume that this is one reason why relative humidity usually is not considered in modelling approaches, which are summarized herein. The high number of recently published research articles on D. suzukii's life cycle suggests that there is already a lot of knowledge available on its biology. However, there are still considerable research gaps mentioned in the literature, which are also summarized herein. Nevertheless, we conclude that sufficient temperature data in the literature are suitable to understand and predict population dynamics of D. suzukii, in order to assist pest management in the field.

Estimating temperature effects on Drosophila suzukii life cycle parameters

“…Since then, numerous studies developed population models for different horticultural, agricultural, and forest insect pests (see for example Gutierrez et al, 1980;Croft & Knight, 1983;Friesland, 1986;Entwistle & Dixon, 1987;Hudes & Shoemaker, 1988;Plantegenest, 1995;Brière et al, 1996;Gosselke et al, 2001;Klüken, 2008;Klüken et al, 2009;Racca et al, 2014; see also Poole, 1978 andde Wit &Rabbinge, 1979). Also for D. suzukii a few modelling studies which predict its population dynamics and/or geographic distribution have already been published since this pest started its invasion in 2008 (see Winkler et al, 2020).…”

“…Especially, temperature can have a strong influence on the life cycle of insect pests such as D. suzukii. For review see, for example, Asplen et al (2015), Hamby et al (2016) and Winkler et al (2020). Consequently, population dynamics modelling of D. suzukii is subjected to a detailed understanding of the development depending on temperature (Racca et al, 2011) in addition to other potential driving factors such as humidity.…”

“…A large number of studies focused on the influence of temperature on D. suzukii's life cycle have already been published (see Winkler et al, 2020). Population increase of D. suzukii was found to be highest at 21 ∘ C (Tochen et al, 2014;Ryan et al, 2016), whereas hot summers with temperatures higher than 30 ∘ C (Harris et al, 2014;Kinjo et al, 2014;Tochen et al, 2014;Ryan et al, 2016;Evans et al, 2018) can reduce population size (Gutierrez et al, 2016;Tochen et al, 2016;Eben et al, 2018) and consequently infestation risk for ripening fruits.…”

“…For a very short period of time, winter morph flies are also able to survive low temperatures up to −7.5 ∘ C (Stockton et al, 2019). There are also substantial data on temperature-dependent life cycle parameters available to understand and predict D. suzukii population dynamics (Winkler et al, 2020). Indeed, some modelling studies, which considered these data, have already been published (see Winkler et al, 2020).…”

“…The high number of published articles, during roughly the past 10 years, on D. suzukii's life cycle suggests that there is already a lot of knowledge available on its biology. Nevertheless, there are still considerable future research perspectives mentioned in the literature: for example, (i) cold hardening related to temperature effects, (ii) almost all life cycle parameters related to humidity effects, (iii) considering host phenology related to modelling, and (iv) the impact of natural enemies on D. suzukii population dynamics (see Winkler et al, 2020). Already existing population dynamics models still need to be linked to crop phenology and weather forecasts to assist advisors and growers to control D. suzukii in the field (Wiman et al, 2014).…”