Dry stress decreases areas suitable for Neoleucinodes elegantalis (Lepidoptera: Crambidae) and affects its survival under climate predictions in South America

Projections of climate change show some regions of the world getting warmer, colder, dryer or wetter. Consequently, the effects of climate change on insect pests can alter the threat to agricultural systems. As a result of changed climate, areas can become more or less suitable for insect pests. Neoleucinodes elegantalis is one of the major pests of solanaceous crops in South America. Host plants for N. elegantalis are widely present in South America, however, N. elegantalis is absent from many regions in South America. Hence, future climate effects on suitability for development and spread of N. elegantalis in South America should be investigated. Due to these reasons, we developed a model of the climate for N. elegantalis using CLIMEX software for South America using A2 Special Report on Emissions Scenarios (SRES) for 2030, 2050, 2070 and 2100 and using two models, CSIRO-Mk3.0 and MIROC-H. The results of both models indicate that areas in South America that are climatically suitable at the present time will become climatically unsuitable for N. elegantalis by 2100 as a consequence of progressive increase of dry stress. This was confirmed using developmental bioassays, where survival was lowest at low relative humidity levels. There are also altering areas that are currently unsuitable that become suitable in the future. These results are helpful in developing future strategies to take advantage of new opportunities in solanaceous crops in regions that may be unsuitable for N. elegantalis and provide important information for anticipated possible risks of infestation of N. elegantalis.