Global change and adaptive biosecurity: managing current and emerging Aleurocanthus woglumi threats to Europe.

Global climate changes undermine the effectiveness of 'set and forget' phytosanitary regulations. Uncertainties in future greenhouse gas emission profiles render it impossible to accurately forecast future climate, thus limiting the ability to make long-term biosecurity policy decisions. Agile adaptive biosecurity frameworks are necessary to address these climatic uncertainties and to effectively manage current and emerging threats. This paper provides opinions on these issues and presents a case study focusing on the threats posed by Aleurocanthus woglumi (citrus blackfly) to Europe. It delves into the biology of the species, its preferred hosts, and how climate change could affect its spread. Utilizing a bioclimatic niche model, the paper estimates the potential distribution of A. woglumi in Europe under recent historical and medium-term future conditions, revealing a potential expansion of its range into higher elevations and more northern regions by the year 2050. The main aim is to leverage the results to showcase the system's sensitivity to likely emission scenarios, essentially stress-testing for potential emerging threats to biosecurity policies and phytosanitary regulations. The results underscore the significance of considering global change factors in pest risk assessment and phytosanitary regulations for effective risk mitigation. Consequently, adaptive biosecurity measures are essential, encompassing horizon scanning, enhanced targeted surveillance, periodic updates of risk assessments, and adjustments to regulations. For instance, biosecurity risk management could involve establishing a set of trigger conditions to prompt updates of risk assessments, such as identifying a zone where the confirmed establishment of a pest signifies a significant change in the pest risk profile. For jurisdictions containing areas modeled as being climatically suitable under historical climates or future climate scenarios, we caution against importing untreated host materials from regions that are likely to become suitable habitats for A. woglumi in the future. Moreover, it is important to consider both present and future climate change scenarios when making decisions to effectively address the threats posed by invasive species. In the case of highly impactful invasives, investing in preemptive biological control measures may prove to be a prudent choice.

Wing Shape Variation between Terrestrial and Coastal Populations of the Invasive Box Tree Moth, Cydalima perspectalis, in Croatia.

The box tree moth (Cydalima perspectalis Walker, 1859; Lepidoptera: Crambidae) is an invasive species naturally distributed in Asia. The caterpillars in all developmental stages cause damage through defoliation of plants, and ultimately the death of the plant itself may occur. It is possible to recognize this species by its silk barriers and threads, and in the case of an intense attack, the entire plant will be covered with them. In Europe, this species' presence was first recorded in 2007 in Germany and the Netherlands, and it is now widely distributed. In Croatia, its existence was first recorded in 2012, in Istria, while substantial damages were recorded in 2013. This work aimed to determine the morphological variability of C. perspectalis from Croatia and assess its invasive character, the possibility of flight, and the risk of further spread. The methods of geometric morphometrics were used as the analysis of wing shape. A total of 269 moths from different locations in Croatia were collected, the upper wings of males and females were analyzed using 14 landmarks. Significant differences in wing shapes between terrestrial and coastal populations were found, as well as subtle wing shape sexual dimorphism. The implications of this variability in species invasiveness and capacity of spread are discussed in this paper. We also extrapolate the usefulness of our results and suggest strategies for predicting and managing invasive species.

Weather Conditions and Maturity Group Impacts on the Infestation of First Generation European Corn Borers in Maize Hybrids in Croatia.

Overwintering success and weather conditions are the key factors determining the abundance and intensity of the attack of the first generation of European corn borers (ECB). The tolerance of maize to the 1st generation of ECB infestation is often considered to be connected with the maize maturity time. The aims of this research were (I) to examine the reactions of different maize FAO maturity groups in term of the damage caused by ECB larvae, (II) to analyze the influence of four climatic regions of Croatia regarding the damage caused by ECB larvae, and (III) to correlate observed damage between FAO maturity groups and weather conditions. First ECB generation damage has been studied in the two-year field trial with 32 different hybrids divided into four FAO maturity groups (eight per group) located at four locations with different climatic conditions. The results showed a lack of correlation between the FAO maturity group and the percent of damage. The percent of damage was positively correlated with the average air temperature in June (r = 0.59 for 2017 and r = 0.74 in 2018, p = 0.0001) within the range from 20 to 24.5 °C and was negatively correlated with the relative air humidity (r = -0.58 in 2017 and r = -0.77 in 2018, p = 0.0001) within the range of 50% to 80%. Our results provide a better understanding of the different factors that influence ECB damage. The obtained data could be used to predict the damage from the first generation of ECB under the weather conditions of different regions.