.................................................................................................................................................................................................... 4 Introduction ............................................................................................................................................................................................

This study concerns the cytotaxonomic investigations on twelve species belonging to three sections from the genus Vicia in Iran. A taxonomic background of the genus is given in brief. The previous counts reported for the genus in Index to plant chromosome number are summarized. In addition to one new count, the chromosome numbers of four species are reported for the first time. Briefly, the ...

the genus astragalus l. (fabaceae) is reviewed from both phyloenetic and taxonomic points of view. as the largest genus of flowering plants it has attracted many researchers, but much work remains to be done. a short taxonomic history with special focus on infrageneric classification of the genus, a list of phylogenetic studies including the applied markers and sampling strategies as well a...

this study concerns the cytotaxonomic investigations on twelve species belonging to three sections from the genus vicia in iran. a taxonomic background of the genus is given in brief. the previous counts reported for the genus in index to plant chromosome number are summarized. in addition to one new count, the chromosome numbers of four species are reported for the first time. briefly, the res...

new evidence gained by the study of foraminifera from khuzestan province in southwest iran reveals that the basal limit of the genus heterostegina is not restricted to the eocene epoch. by introducing a new species of this genus (h. rezvaninejadi), this study shows that the early appearance of this genus should be lowered down further still, at least, into the middle paleocene.

Bacterial symbionts have long been suspected to be the true producers of many drug candidates isolated from marine invertebrates. Sponges, the most important marine source of biologically active natural products, have been frequently hypothesized to contain compounds of bacterial origin. This symbiont hypothesis, however, remained unproven because of a general inability to cultivate the suspect...

Many drug candidates from marine and terrestrial invertebrates are suspected metabolites of uncultured bacterial symbionts. The antitumor polyketides of the pederin family, isolated from beetles and sponges, are an example. Drug development from such sources is commonly hampered by low yields and the difficulty of sustaining invertebrate cultures. To obtain insight into the true producer and fi...