Predicting future distribution and generation number of mulberry scale, Pseudaulacapis pentagona under climate change scenarios in Turkiye

Mulberry scale, Pseudaulacaspis pentagona (Targioni-Tozzetti) (Hemiptera: Diaspididae) is a serious pest of orchards, forests, and woody ornamental vegetation in Turkiye. Climate change may significantly affect the bio-ecology and the geographical distribution of the scale insect. The development threshold (C) and the temperature constant (K) of P. pentagona were determined by the linear regression model to study of this scenario. Non-linear regression models were used to estimate the optimum temperature and the low and the high temperature thresholds. The possible new areas of spread of P. pentagona in Turkiye were forecasted until the year 2098 by using HadGEM2-ES RCP4.5 and HadGEM2-ES RCP8.5 climate scenarios together with changes in generation time and positive intrinsic rate of increase of Mulberry scale. These values were obtained at different temperatures under laboratory conditions. The terrestrial annual average temperature grid data with 20 x 20 km resolution, obtained from Turkish State Meteorological Service, were deployed to create the projection maps. According to the results obtained, it is predicted that P. pentagona will be able to complete its development and would cause an outbreak in Black Sea, Eastern Anatolia, South-East Anatolia regions, where it could not develop or complete its generation in reference periods 1971-2000, until the year 2070. If the average temperature continues increase, it will not be possible for P. pentagona to develop on the Mediterranean and Aegean coasts, because high temperatures negatively affect reproductive capacity.