MORPHOLOGICAL, GENETICAL AND ECOGEOGRAPHICAL CHARACTERIZATION OF LONG-WINGED SPECIES OF ONOBRYCHIS SECT. ONOBRYCHIS (FABACEAE) IN IRAN

In this study, 30 specimens (6 populations) from long-winged species of Onobrychis sect. Onobrychis including O. verae Širj., O. gontscharovii Vassilcz., O. ptychophylla Širj. & Rech. f., O. sosnovskyi Grossh. and O. araxina Schischkin were collected from their natural habitats in Iran. The specimens were biometrically assessed using 45 quantitative and 15 qualitative morphological characters. In order to study the genetic variations of different species, nucleotide sequence data from the internal transcribed spacer of the nuclear rRNA genes (ITS) were obtained. Data regarding longitude, latitude, altitude, slope inclination, slope direction, substrate, min/max annual temperatures, number of rainy days, annual precipitation as well as soil traits including texture, electrical conductivity, organic carbon, total nitrogen, available phosphorus and potassium, total neutralizing value, pH, and saturation percentage were recorded in each sample site. Cluster analysis of morphological characters showed two major groups separating northwest species from northeast ones. Furthermore, the ITS data analysis results showing two main groups, which are exactly in concordance with morphological groups. Also canonical correspondence analysis (CCA) of ecological data showed the precipitation, rainy days, sand% and silt% as the most effective factors for this separation. Furthermore it showed the effect of ecological factors on each species. Onobrychis araxina Schischkin is recorded for the first time from Azerbaijan Gharbi province, Iran. An identification key to the long-winged species of section Onobrychis in Iran is presented.