Incidence of Fusarium oxysporum on commercial seeds of Diplotaxis spp., Eruca sativa , Lactuca sativa and Valerianella locusta.

The economical importance of “ready to use” fruit and vegetable products (4th range), greatly increased in the last ten years; to date Lactuca sativa, Cichorium spp., Eruca sativa, Diplotaxis spp and Valerianella locusta cover a great part of the vegetable market. The final products quality can be achieved using healthy seeds and appropriate agronomic techniques. One of the most important pathogens of these species is Fusarium oxysporum: infected plants are usually stunted, leaves turn pale green to golden yellow and later wilt, wither, die and drop off progressively upward from the stem base. Browning occur in vascular tissue (xylem) of roots and lower stem, while roots may decay and seedlings sometimes wilt and die. Surviving seeds can act as source of primary inoculum. In the present work more than 100 seed lots of Diplotaxis spp., Eruca sativa, Lactuca spp. and Valerianella locusta have been analyzed, in order to assess the incidence of F. oxysporum on commercial seeds. Our data highlight the very low frequency of F. oxysporum infection and the presence of other Fusarium species belonging to Gibberella fujikuroi complex.