New host plants of Spiroplasma citri in Turkey
The host range (non citrus-hosts) of Spiroplasma citri (EU quarantine pest, Annex II/A2) has been studied in the €ukurova region which is the main citrus-growing region of Turkey. Up till now, in the Mediterranean region, only Catharanthus roseus, Hirschfeldia incana and Sisymbrium irio were known as natural non-citrus hosts of S. citri. During this study, approximately 250 samples of plants representing 27 species in 15 families have been tested by ELISA from 1988 to 1990, and attempts to culture the causal agent of stubborn were then carried out for plants found to be infected by ELISA. The results obtained showed that, in addition to Catharanthus roseus, S. citri was isolated from Crepis echioides, Echium sp. and Sesamum indicum (sesame), which are reported for the first time as natural host plants of S. citri. S. citri was also detected by ELISA in Digitaria sanguinalis, Salsola kali and Sorghum halepense, but could not be isolated from these plants. It was also found that a vector of S. citri, Circulifer opacipennis is abundant and commonly found on sesame. The authors concluded that among these new host plants, Sesamum indicum is the most important, and stressed that it can play a significant role in the epidemiology of the disease, as it is widely grown in the €ukurova region and highly infected.
Sources
Kersting, U.; Sengonca, €.; €inar, A. (1992) Detection of Spiroplasma citri in non-citrus host plants and their associated leafhopper vectors in southern Turkey.
FAO Plant Protection Bulletin, 40 (3), 89-94