CHARACTERIZATION OF PHYTOMONAS ISOLATED FROM FRUITS BY ELECTROPHORETIC ISOENZYMES AND KINETOPLAST-DNA ANALYSIS

Two flagellates of the family trypanosomatidae were isolated from the fruits of Lycopersicon esculentum (tomato) and Annona cherimolia (cher imoya) in the southeastern region of Spain. The isolates were characte rized by isoenzyme analysis using nine different isoenzymes and by ana lysis of kinetoplast DNA (kDNA) restriction fragment length polymorphi sm using four different restriction endonucleases. Most of the isoenzy mes were unable to distinguish between the two fruit isolates, while t hey were all able to distinguish these two from four other Phytomonas isolates, three of which were from laticiferous plants, i.e. Euphorbia characias, E. hirta and E. hyssopifolia, and one was a phloem-restric ted isolate associated with Hartrot disease. Only the enzyme superoxid e dismutase was able to differentiate between the two fruit isolates. Electrophoretic and restriction endonuclease analysis of kDNA minicirc les, using four restriction enzymes, showed similar if not identical r estriction cleavage patterns of the minicircles of the two isolates fr om fruits, while the patterns were different for the other isolates. T hese results confirm the hypothesis that the two isolates from fruits constitute a group of trypanosomatids that are the same or closely rel ated and that this group can parasitize more than one host plant.