Spatial and temporal features and social composition of vine-infesting colonies of Kalotermes flavicollis in Sherry vineyards (Spain)

In Andalusia (SW Spain), Kalotermes flavicollis (Isoptera: Kalotermitidae) is considered one of the major pests of Sherry vineyards. Colonies of this termite progressively debilitate the vines, causing the sequential loss of the arms and resulting in serious economic losses, since Sherry vineyards yield important registered designation of origin wines. A detailed investigation aimed to analyse the patterns of infestation of this termite, was performed during 15 months in nine districts of the Sherry area on differently aged vines of the “Palomino fino” variety. Samples were collected twice a month, cutting randomly selected vines into six sections, which were carefully opened to pick up all eggs and individuals. Collected termites were then recognized, separated and counted according to the developmental stage or caste (eggs, larval and nymphal stages, pseudoergates, soldiers, alates, reproductives). The results allowed to get the social composition of vine attacking colonies and to detect, for different castes and developmental stages, significant differences in the spatial distribution inside the vine and in the numerical trends over the seasons. The biological meaning of these findings will be discussed.