ABSTRACT
Historical trends and models suggest that sustained wheat production will be more difficult under projected climate change (Asseng et al., 2014; Challinor et al., 2014; Wilcox and Makowski, 2014). Unfortunately, these projections are limited in that they do not incorporate constraints on production from diseases, weeds and insect pests. Incorporating these factors is a significant challenge because information is limited. For insect pests, although trends noted for insects in general (e.g. Parmesan and al, 1999; Parmesan and Yohe, 2003; Parmesan, 2006; Bebber, 2015) might apply, specifics will vary widely because the potentially contributing mechanisms are diverse. These include changes to survival rates in winter and summer, population growth rates, shifts in phenology and changes in interspecific interactions (Kiritani, 2013). Effects that can
come into play include direct effects of warming and increasing atmospheric CO2 on pest fecundity and population dynamics (Dyer et al., 2013), shifts in geographic or elevational ranges of pests (Bebber et al., 2013; Bebber, 2015), expression of plant resistance factors affecting pests (Tyler and Hatchett, 1983; Currie et al., 2014), changes to feeding behaviour, phenology and voltinism (Ziter et al., 2012), and alterations to trophic interactions and biological control mechanisms (Gutierrez et al., 2008; Romo and Tylianakis, 2013; Thomson et al., 2010; Gillespie, et al. 2013; Eigenbrode et al., 2015).
