Hewitt, KGPhillips, CBHofmann, RWBall, OJLuo, DPopay, AJ2024-06-132023-11-102024-06-132024-05-282463-2872https://hdl.handle.net/10182/17288Water is essential to plant growth, driving interactions between plants, herbivorous insects and fungal Epichloë endophytes. However, water availability fluctuates, a phenomenon intensified by climate change, challenging the success of New Zealand’s pastoral industry. The impacts of climatic changes, such as intensifying drought, on pastoral insect pests have received little attention. In a no-choice bioassay, African black beetle (ABB) were fed semi-synthetic diets containing freeze-dried foliage material from drought-exposed and well-watered perennial ryegrass containing endophyte strains AR37 or NZCT, or with material free of endophyte (Nil). Diet consumption, beetle weight change, fungal alkaloid concentrations, phytohormones, and NRI (nitrogen reflectance index) concentrations were measured and compared. Except for AR37, ABB consumed more diets containing drought-exposed rather than well-watered material, with a 61% increase in Nil and a 50% increase in diets containing NZCT, though these effects were not accompanied by corresponding ABB weight changes. Here, we discuss the implications of these results on ABB damage in New Zealand pastures in the context of increasing drought and illustrate how spatial patterns of ABB damage could change over the next 75 years. Areas that do not currently have high populations of ABB such as Manawatū-Whanganui, Wairarapa and Marlborough will become increasingly vulnerable to damage.13 pagesen© 2023 Journal of New Zealand Grasslands.alkaloidsclimate changeEpichloëHeteronychus aratorinsect feedingLolium perennepasture resilienceJournal Article10.33584/jnzg.2023.85.36642463-2880ANZSRC::370704 Surface water hydrologyANZSRC::310406 Evolutionary impacts of climate changeANZSRC::300304 Animal protection (incl. pests and pathogens)ANZSRC::300404 Crop and pasture biochemistry and physiologyANZSRC::300307 Environmental studies in animal productionhttps://creativecommons.org/licenses/by-nc-nd/4.0/Attribution-NonCommercial-NoDerivatives