Predicting the impact of climate change on the future distribution of the invasive tomato pinworm Tuta absoluta (Meyrick) using life cycle simulation modelling

Authors: AZRAG, ABDELMUTALAB - International Centre Of Insect Physiology And Ecology; OBALA, FRANCIS - International Centre Of Insect Physiology And Ecology; TONNANG, HENRI - International Centre Of Insect Physiology And Ecology; NDLELA, SHEPARD - International Centre Of Insect Physiology And Ecology; Hogg, Brian; MOHAMED, SAMIRA - International Centre Of Insect Physiology And Ecology

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/26/2023
Publication Date: 9/30/2023
Citation: Azrag, A.G., Obala, F., Tonnang, H.E., Ndlela, S., Hogg, B.N., Mohamed, S.A. 2023. Predicting the impact of climate change on the future distribution of the invasive tomato pinworm Tuta absoluta (Meyrick) using life cycle simulation modelling. Scientific Reports. https://doi.org/10.1038/s41598-023-43564-2.
DOI: https://doi.org/10.1038/s41598-023-43564-2

Interpretive Summary: The South American tomato leafminer, an invasive moth originally from Peru, is the most damaging insect pest of tomatoes in many countries. Using computer modeling software, we predicted the risk of establishment and spread of tomato leafminer under current climatic conditions and those projected for the years 2050 and 2070. The models projected that large areas of the Southern Hemisphere are more suitable than the Northern Hemisphere for establishment of tomato leafminer under current and future climatic scenarios. However, risk to Europe, the USA, Southern Africa, and some parts of Asia is projected to increase under future climatic scenarios. Under current conditions, tomato leafminer could complete between 6-16 generations per year in suitable areas, although 1-3 additional generations are likely in most parts of the world in the future, indicating that populations of tomato leafminer could increase by 10 to 40-fold per year. The information from our models could guide stakeholders and decision-makers in developing strategies to minimize the spread and impacts of this pest in specific agro-ecological zones.

Technical Abstract: The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is the most damaging insect pest threatening the production of tomato, Solanum lycopersicum L. (Solanaceae), and other solanaceous vegetables in many countries. In this study, we predicted the risk of establishment and number of generations for T. absoluta in the current climatic conditions under two Shared Socioeconomic Pathways (SSPs) (SSP2-4.5 and SSP5-8.5) of the years 2050 and 2070 using Insect Life Cycle Modelling (ILCYM) software. We used a temperature-dependent phenology model of T. absoluta to project three risk indices viz., establishment risk index (ERI), generation index (GI), and activity index (AI) based on temperature data obtained from WorldClim database. The model projected large suitable areas for T. absoluta establishment in the Southern hemisphere under current and future climatic scenarios, compared to the Northern part. However, the risk of T. absoluta is expected to increase in Europe, USA, Southern Africa, and some parts of Asia under future climatic scenarios. Under current conditions, T. absoluta could complete between 6-16 generations per year in suitable areas. However, an increase in GI between 1-3 generations per year is projected for most parts of the world in the future, with an increase in AI between 1-4, indicating that the population of T. absoluta might increase by 10-40-fold per year in the future. Our results provide information on the risk of T. absoluta which could guide the stakeholders and decision-makers to develop control strategies adapted for specific agro-ecological zones to minimize the risk of this pest in the horticultural industry.