Ecological and cenotic characteristics of Colchicum laetum (Colchicaceae) habitats in the Volgograd region

During the flowering period of Colchicum laetum Stephen (September 16–19, 2020), seven habitats were studied in the Volgograd region. C. laetum occurs on small (0.006–4 ha) unploughed areas of the steppes adjacent to gullies. In the community, 28 species of vascular plants were recorded, including C. laetum, only 10 species vegetated (from 2 to 7 in the community): Artemisia austriaca Jacq., A. santonicum L., Bassia prostrata (L.) Beck, Cynanchum acutum L., Dianthus polymorphus M. Bieb., Euphorbia seguieriana Neck., E. virgata Waldst., Grubovia sedoides (Pall.) GL Chu, Limonium bungei (Claus) Gamajun., Medicago falcata L. The participation of C. laetum is from single individuals to quite abundant, with a projective cover not exceeding 5%. A preliminary assessment of habitat by vegetation according to the Ramenskoye scales showed that one community is quite rich, one is rich and one is not rich. The humidification is from dry steppe to desert. Only one community does not experience anthropogenic impact. In the second the arrival of vehicles was marked. In the third grazing is carried out, accompanied by a failure.

ECOLOGICAL FEATURES OF MEADOW PHYTOCENOSIS AT THE DRAINING FACILITY

Проблема и цель. Осушительный объект Тинки-II является уникальным комплексом вследствие отличительных природных условий и длительного срока мелиоративного воздействия, начатого в середине 1950-х годов с целью осушения болотной торфяной почвы и вовлечения ее в сельскохозяйственный оборот. Позднее, в 1980-х годах, на осушаемой территории было введено двойное регулирование водного режима посредством дождевания. С конца 1990-х годов осушаемые земли не использовались. Сейчас агроландшафты преобразовались в природные сообщества. Финансирование мониторинговых и уходных работ за элементами осушительной системы со стороны государства не оказывается. Это, в свою очередь, привело к нарушению мелиоративных и агрохимических свойств торфяной почвы и проявлению деградации. Почва как биокосная система неразрывно связана с растительными сообществами. Методология. Проведенный автором совместно с сотрудниками ВНИИГиМ в 2010-2020 годах мелиоративный, почвенно-экологический и фитосоциологический мониторинг определил свойства почвы, видовой состав луговых трав, тип ассоциации обследуемого участка луга. Более ценной информацией, которая будет использована при разработке рекомендаций по использованию территории в качестве кормовых угодий, является познание взаимосвязей экологических факторов с растениями. С этой целью проведены исследования по общеизвестным классическим методикам. Результаты. Большее видовое разнообразие, различие по высоте и фитомассе установлено у злаков с преобладанием таких, к примеру, как Elytrigia repens, Alopecúrus praténsis и Bromopsis inermis, чуть меньше определено разнотравья из разных семейств Urtica dioica, Conium maculatum и Chaerophyllum temulum, еще меньше бобовых Lathyrus pratensis, Medicago falcata, Trifolium pratense. Заключение. В результате выявлены качественные и количественные отличия растительных сообществ вблизи магистрального канала с высоким увлажнением почвы, вблизи п. Полково с хорошей освещенностью и вблизи леса в большей степени с рассеянным светом. Фитомасса растений выше на участке вблизи п.Полково. Problem and purpose. Tinki-II drainage facility is a unique complex due to the distinctive natural conditions and the long-term reclamation impact, which began in the mid-1950s with the aim of draining the peat bog soil and bringing it into agricultural circulation. Later, in the 1980s, a double regulation of the water regime by means of sprinkling was introduced in the drained area. Since the late 1990s, the drained land has not been used. Nowadays, agricultural landscapes have been transformed into natural communities. The government does not provide funding for monitoring and maintenance of the drainage system elements. This, in turn, has led to the disturbance of the ameliorative and agrochemical properties of the peat soil and the manifestation of degradation. Soil as a bio-inert system is inextricably linked with plant communities. Methodology. The land reclamation, soil-ecological and phytosociological monitoring carried out by the author together with the VNIIGiM employees in 2010-2020 has determined the soil properties, speciescomposition of meadow grasses, and the type of association of the surveyed meadow area. The knowledge of the relationship of environmental factors with plants is more valuable information that will be used when developing recommendations for the use of the territory as forage lands. For this purpose, research has been carried out using well-known classical methods. Results. Greater species diversity, diferences in height and phytomass were found in cereals with a predominance of Elytrigia repens, Alopecúrus praténsis, and Bromopsis inermis. There were slightly less forbs from diferent families of Urtica dioica, Conium maculatum and Chaerophyllum temulum, and even less legumes of Lathyrus pratensis, Medicago falcata and Trifolium pratense were identifed. Conclusion. As a result, the qualitative and quantitative diferences of plant communities near the main canal with high soil moisture were revealed near the settlement of Polkovo with good illumination and near the forest, to a greater extent with difused light. The phytomass of plants was higher in the area near Polkovo.

An analysis of the Medicago falcata s.l. alfalfas collected in the ex-USSR territories for the fullness of their coverage

Background. The collection of wild yellow alfalfas from the Medicago falcata s.l. complex maintained at the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) is a unique genetic stock collected while exploring the ex-USSR territories from 1924 to 2018. It includes Medicago falcata L. proper, M. borealis Grossh., M. romanica Prod., M. quasifalcata Sinsk., M. difalcata Sinsk., and M. glandulosa David. Gap analysis makes it possible to assess the sufficiency of VIR’s collecting efforts in a certain locality or administrative unit and plan further collecting activities to ensure comprehensive conservation of sickle alfalfa genetic diversity.Material and methods. Databases of the Perennial Forage Crop Genetic Resources Department at VIR, and digital maps of administrative subdivisions of Russia and neighboring countries served as the research material. The ex-USSR administrative subdivisions were accepted as operational units. For each of them, the number of ser. Falcatae Vass. species and the number of accessions per administrative subdivision were taken into account. Statistical data processing included construction of frequency tables and differentiated mapping.Results. The coordinates of collection sites were identified for 446 accessions. Collections of six wild species within the studied complex were analyzed across the ex-USSR space, and in more detail in Krasnodar Territory.Conclusion. The target areas were identified for further collecting activities. For Russia, the prioritized regions where the collection could be replenished are the northern frontier of the area of sickle alfalfa distribution in the European part and its eastern borderline in Siberia, both characterized by extreme environmental conditions. To increase the geographic diversity of the collection, additional collecting efforts are required, along with mobilization of accessions from the neighboring countries.

Molecular characterisation and expression analysis of NAC transcription factor genes in wild Medicago falcata under abiotic stresses

The No apical meristem–Arabidopsis transcription activation factor–Cup-shaped cotyledon (NAC) proteins play vital roles in plant development processes and responses to abiotic stress. In this study, 146 unigenes were identified as NAC genes from wild Medicago falcata L. by RNA sequencing. Among these were 30 full-length NACs, which, except for MfNAC63, MfNAC64 and MfNAC91, contained a complete DNA-binding domain and a variable transcriptional activation region. Sequence analyses of MfNACs along with their Arabidopsis thaliana (L.) Heynh. counterparts allowed these proteins to be phylogenetically classified into nine groups. MfNAC35, MfNAC88, MfNAC79, MfNAC26 and MfNAC95 were found to be stress-responsive genes. The eight MfNAC genes that were chosen for further analysis had different expression abilities in the leaves, stems and roots of M. falcata. Additionally, their expression levels were regulated by salinity, drought and cold stress, and ABA. This study will be useful for understanding the roles of MfNACs in wild M. falcata and could provide important information for the selection of candidate genes associated with stress tolerance.