Impacts of climate change on infestations of Dubas bug (Ommatissus lybicus Bergevin) on date palms in Oman

Abstract

Climate change has determined shifts in distributions of species and is likely to affect species in the future. Our study aimed to (i) demonstrate the linkage between spatial climatic variability and the current and historical Dubas bug (Ommatissus lybicus Bergevin) distribution in Oman and (ii) model areas becoming highly suitable for the pest in the future. The Dubas bug is a pest of date palm trees that can reduce the crop yield by 50% under future climate scenarios in Oman. Projections were made in three species distribution models; generalized linear model, maximum entropy, boosted regression tree using of four global circulation models (GCMs) (a) HadGEM2, (b) CCSM4, (c) MIROC5 and (d) HadGEM2-AO, under four representative concentration pathways (2.6, 4.5, 6.0 and 8.5) for the years 2050 and 2070. We utilized the most commonly used threshold of maximum sensitivity + specificity for classifying outputs. Results indicated that northern Oman is currently at great risk of Dubas bug infestations (highly suitable climatically) and the infestations level will remain high in 2050 and 2070. Other non-climatic integrated pest management methods may be greater value than climatic parameters for monitoring infestation levels, and may provide more effective strategies to manage Dubas bug infestations in Oman. This would ensure the continuing competitiveness of Oman in the global date fruit market and preserve national yields.

Assessing the impact of climate change on the worldwide distribution of Dalbulus maidis (DeLong) using MaxEnt

“…For the future projections for 2050 and 2070, the global climate models (GCMs) MIROC5, HadGEM2‐AO and HadGEM2‐ES under the representative concentration pathways (RCP) RCP4.5 and RCP8.5 were used for both species. Theses GCMs have been used widely to assess the spatial distributions of many species based on climate change, ecosystems and other long timescale components of the earth, including the simulations of the currently available RCPs . These models were three of the models that were used in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) and the associated cycle of the fifth phase of the CMIP5 (http://www.ipcc.ch/report/ar5/wg1/).…”

“…Theses GCMs have been used widely to assess the spatial distributions of many species based on climate change, ecosystems and other long timescale components of the earth, including the simulations of the currently available RCPs. [39][40][41] These models were three of the models that were used in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) and the associated cycle of the fifth phase of the CMIP5 (http://www.ipcc.ch/ report/ar5/wg1/). 42 These models take into account various factors, which includes greenhouse gas emissions, aerosols, solar irradiance, ozone, and others.…”

Modelling the potential effects of climate factors on Dubas bug (Ommatissus lybicus) presence/absence and its infestation rate: A case study from Oman

“…Despite the fact that physiological knowledge becomes better integrated into species distribution models to make robust predictions of range shifts in novel or non‐equilibrium contexts such as invasion and climate factors, the impact of climate variables on the increase in the infestation stress and occurrence of DB outbreaks warrants detailed exploration in relation to different climate zones. Although numerous studies have determined the ecology of DBs under field and under semi‐field conditions, there is limited focused research on the spatial distribution and modelling of DB presence/absence and density in relation to climate factors including weather stations and microclimate data on a large scale . There is a gap in research for predicting and forecasting the occurrences of DB infestations in Oman, which has wider benefits to countries that are similarly affected by these infestations.…”

Resistance to deltamethrin and fenitrothion in dubas bug, Ommatissus lybicus de Bergevin (Homoptera: Tropiduchidae) and possible biochemical mechanisms

“…Dubas bug, Ommatissus lybicus de Bergevin 1930 (Homoptera: Tropiduchidae), is demonstrated as the serious pest of date palm in Oman and causes economic losses by reducing the production of quality date fruits [7][8][9][10] . The pest records are also reported from Saudi Arabia, Egypt, Iraq, Israel, Yemen, Pakistan, Qatar, United Arab Emirates (UAE) other than Oman [11][12][13][14] .…”

“…The higher O. lybicus populations can damage the date palms to greater extent and can make 25-50% crop losses 15 . Scientists describing the impacts of climate change on infestation of O. lybicus has declared northern Oman at the edge of risk and stated that it will bear sever pest influxes in future owing to ecological aptness 7 .…”