VARIABILITY IN THE PHLOEM RESTRICTED PLANT TRYPANOSOMES (PHYTOMONAS SPP) ASSOCIATED WITH WILTS OF CULTIVATED CROPS - ISOENZYME COMPARISON WITH THE TOWER TRYPANOSOMATIDS

Plant trypanosomatids (Phytomonas spp)have been isolated from the crud e sap of coconut trees and oil palm trees affected with Hartrot or Mar chitez diseases in South America and Alpinia purpurata affected with w ilt in the Caribbean. They are also commonly isolated from the fruits and latex of Euphorbiaceae or Asclepiadaceae. Thirty-four Phytomonas s tocks were studied by isoenzyme electrophoresis (11 loci) in order to investigate genetic variability in the intraphloemic group. Our result s showed that variability in phloem restricted Phytomonas is very high , and that Marchitez or Hartrot associated trypanosomatids are not rea dily separated into two distinct groups. Moreover, the two isolates fr om Alpinia are very close to the other intraphloemic isolates. The res ults confirm the existence of several distinct groups, comprising of a t least 2 groups of phloem restricted trypanosomatids, not related to the host species, 3 groups of latex trypanosomatids, and one group of fruit trypanosomatids.