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Background Ferula L. is one of the largest and most taxonomically complicated genera as well as being an important medicinal plant resource in the family Apiaceae. To investigate the plastome features and phylogenetic relationships of Ferula and its neighboring genera Soranthus Ledeb., Schumannia Kuntze., and Talassia Korovin, we sequenced 14 complete plastomes of 12 species.  Results The size of the 14 complete chloroplast genomes ranged from 165,607 to 167,013 base pairs (bp) encoding 132 distinct genes (87 protein-coding, 37 tRNA, and 8 rRNA genes), and showed a typical quadripartite structure with a pair of inverted repeats (IR) regions. Based on comparative analysis, we found that the 14 plastomes were similar in codon usage, repeat sequence, simple sequence repeats (SSRs), and IR borders, and had significant collinearity. Based on our phylogenetic analyses, Soranthus, Schumannia, and Talassia should be considered synonymous with Ferula. Six highly divergent regions (rps16/trnQ-UUG, trnS-UGA/psbZ, psbH/petB, ycf1/ndhF, rpl32, and ycf1) were also detected, which may represent potential molecular markers, and combined with selective pressure analysis, the weak positive selection gene ccsA may be a discriminating DNA barcode for Ferula species. Conclusion Plastids contain abundant informative sites for resolving phylogenetic relationships. Combined with previous studies, we suggest that there is still much room for improvement in the classification of Ferula. Overall, our study provides new insights into the plastome evolution, phylogeny, and taxonomy of this genus.

A total of 110 strains of nodule bacteria was isolated from plants Onobrychis transcaucasica and Onobrychis chorassanica. Nodulation study of bacteria in both Onobrychis plant species in microvegetation experiment gave a very low nodulation on plant roots. The intensive nodulation of Onobrychis plants was recorded in vegetation experiment and for Onobrychis transcaucasica the efficiently-nodulating strains were found OT102, OT103, OT117, OT121, OT130, OT136, ОT139, ОT140, while for Onobrychis chorassanica plants—ОC106, ОC107, ОC109, ОC112, ОT103, ОT117 and ОT123 strains. Nucleotide sequencing of the 16S rRNA gene and BLAST analysis showed that nodule bacteria of Onobrychis plants were related to Rhizobium, Burkholderia, Enterobacter and Pantoea genera. It has been shown a possibility of growing up of Onobrychis plants at minimal additional moisture of sabulous soils in the Kyzyl Kum Desert, creating artificial pastures and thereby immobilizing the desert blown sands

Thesium brevibracteatum P.C.Tam was described, based on the specimen L.C.Chiu 5128 collected from Inner Mongolia, China. The name Thesium brevibracteatum Sumnev. is validly published and described for the type (Korotkova E. E. et Titov V. S. 1502) collected from Uzbekistan. T. brevibracteatum P.C.Tam is a later homonym of T. brevibracteatum Sumnev. We propose T. longiperianthium as the replacemen name for T. brevibracteatum P.C. Tam.

To search for an alternative to alfalfa under conditions of salinity and drought, a comparative study was carried out to explore the effect of salinity on the symbiosis of alfalfa and local esparcet species (<i>Onobrychis transcaucasica</i> and <i>Onobrychis chorassanica</i>) inoculated with their nodule bacteria. The salinity of up to 30 mM NaCl insignificantly affected the biomass growth of shoots and roots of alfalfa plants, but the increase in the salinity from 30 to as high as 140 mM NaCl led to the biomass decrease. The salinity produced a double effect on the nodulation process in inoculated alfalfa plants as follows: 1) at 30 - 100 mM NaCl the stimulation of nodulation and increased leghemoglobin activity were observed; 2) at salinity concentrations higher than 100 mM NaCl the suppression of both nodule formation and leghemoglobin activity was observed. Alfalfa plants under inoculation with the <i>Sinorhizobium meliloti</i> 10 strain obtained a considerable resistance to salinity (50 - 80 mM NaCl). The efficient symbiosis of <i>O. transcaucasica</i> plants with <i>Rhizobium</i> sp. OT111 and <i>O. chorassanica</i> plants with <i>Rhizobium</i> sp. OC109 enhanced the adaptation of plants to salinity up to 150 mM NaCl. The gradual growth suppression of both Onobrychis plants species started from 200 mM NaCl, and salinity concentration 300 mM NaCl was critical (sublethal) for plants independently of inoculation by nodule bacteria. In field conditions, <i>O. chorassanica</i> was more resistant to salinity than <i>O. transcaucasica</i>, but minimal irrigation for both species of <i>Onobrychis</i> showed a higher effect on their growth and development than the moderate salinity at the concentration 75 mM NaCl. The lower limit (drought threshold) of drought-resistance of <i>Onobrychis</i> plants was 6% - 8% of soil humidity. In shoot and roots of alfalfa, both <i>Onobrychis</i> plant species subject to salt stress, aldehyde oxidase and xanthine dehydrogenase enzymes and different number of their isoforms as well as their electrophoretic mobilities/activities were found