The relationship between Cerambyx spp. damage and subsequent Biscogniauxia mediterranum infection on Quercus suber forests

In this paper we shall show the first data on the level of Cerambyx spp. beetle damage and the subsequent Biscogniauxia mediterranum (De Not) Kunze fungus infection in the Extremadura region (southwestern Spain). Our results indicate a strong correlation between damage, caused by bad cork removal and pruning practices (injuries that cannot heal and permit the attack of insects), and holes made by beetles (r = 0.86). The relationship between holes and subsequent Biscogniauxia infection was r = 0.91. Different regression models have been proposed in order to find mathematical equations applied to forest health monitoring of wide areas. Additionally, we show the evolution in infection after 14 years in the four different areas. The results indicate an increase in damage by Cerambyx and Biscogniauxia infection after this period. Significant differences were found when comparing the four areas suggesting that local factors can be affecting these pests. Finally, we discuss the possible influence of different sociological, economic and agricultural factors on the management and conservation of Quercus suber forests in southwestern Spain and we propose possible solutions to integrate biological conservation and economic benefits of a sustainable cork industry associated with these Mediterranean forests.