Molecular and micro-morphological evidences of the genus Cuscuta in Iran

Abstract

<em>Cuscuta</em> is the only parasitic genus in <em>Convolvulaceae</em> family. This genus is globally distributed, with most species in the tropics, subtropics, and some in the temperate regions. In this study, the micro-morphological features and molecular evidencesof 12 populations from three species of <em>Cuscuta </em>(<em>C. australis</em>,<em> C. campestris</em>,and <em>C. chinensis</em>) have been considered. In total, seven quantitative and two qualitative characters of pollen were selected and measured. The most important characters include: shape, ornamentation of tectum, exine thickness and colpus length of the pollen. Based on this study, the seed shape and surface support at least for separation of <em>C. australis </em>from other two species. Using nuclear (nrDNA ITS) marker, we reconstructed phylogenetic relationships within three species of <em>Cuscuta</em>. This data set was analyzed by phylogenetic methods including Bayesian, Maximum likelihood, and Maximum parsimony. In phylogenetic analyses, all members of three species formed a well-supported clade (PP=1, ML/BS=100/100) and divided into two major clades (A and B). Clade A is composed of specimens of<em> C. australis.</em> Two species of <em>C. campestris </em>and <em>C. chinensis </em>are nested in clade B. Neighbor-Net diagram demonstrated separation of the studied populations. <br /> The results showed that, micro-morphological and molecular data provide reliable evidence for separation of these species.<br /> <strong> </strong>