This chapter will take into consideration only Seiridium canker of cypress because of its spread at a global level and the serious damage and economic losses that it causes to many Cupressaceae in forests, windbreaks and ornamental plantings. Information is given on their detection, infection biology and epidemiology, as well as on management strategies and tactics, which include avoidance, exclusion, eradication, protection (using fungicides and biological control agents), use of resistant clones, and integration of different control methods.

Common cypress (Cupressus sempervirens L.) is an integral feature of the landscape of many Mediterranean regions (particularly in Tuscany). Furthermore, common cypress has multiple uses as ornament, timber, windbreaks, recovery of deteriorated soils, protection of slopes and the production of essential oils. During the last three decades, Seiridum cardinale canker of cypress has caused severe losses in woods, windbreaks and ornamental plantings in the Mediterranean area, significantly limiting the use and cultivation of this tree. In this paper we describe `Italico' and `Mediterraneo', two C. sempervirens varieties which were patented in 2004 for their resistance to cypress canker. Both varieties are particularly suitable for ornamental purposes because of their fastigiated columnar habit and the low production of male flowers and cones. `Italico' and `Mediterraneo' represent the recent result of the breeding programme on cypress, in progress since the 1970s. This program aims at: 1) obtaining a high number of canker-resistant cypress clones and multi-clonal varieties to be used for ornamental plantings and windbreaks and 2) finding mother trees for the production of improved seed for reforestation purposes.

The biology of the patliogciiic agent ol plane tvcc cmkcr {Ceratocystis fimbriata Lplatani), the vectors of the disease and the results of soinc preventive and curative trcitmonts arc described in detail.

The life cycle oi Seiridium cardiriale, the prineipal symptoms of the cypress eanker disease, the results of ehemieal eontrol, and the research directed toward genetie improvement of Italian cypress for resistanee to the canker are deseribed.

Ramets of 200 clones of Cupressus sempervirens were inoculated with 6 isolates of Seiridium cardinale. No significant differences were found among isolates, while there were highly significant differences among clones when length and width of canker were assumed as discriminating traits.