Seed Dormancy Class and Ecophysiological Features of Veronicastrum sibiricum (L.) Pennell (Scrophulariaceae) Native to the Korea Peninsula

Veronicastrum sibiricum is a perennial species distributed in Korea, Japan, Manchuria, China, and Siberia. This study aimed to determine the requirements for germination and dormancy break of V. sibiricum seeds and to classify the kind of seed dormancy. Additionally, its class of dormancy was compared with other Veronicastrum and Veronica species. V. sibiricum seeds were permeable to water and had a mature embryo during seed dispersal. In field conditions, germination was prevented by physiological dormancy, which was, however, relieved by March of the next year, allowing the start of germination when suitable environmental conditions occurred. In laboratory experiments, the seeds treated with 0, 2, 4, 8, and 12 weeks of cold stratification (4 °C) germinated to 0, 79, 75, 72, and 66%, respectively. After the GA3 treatment (2.887 mM), ≥90% of the seeds germinated during the four incubation weeks at 20/10 °C. Thus, 2.887 mM GA3 and at least two weeks at 4 °C were effective in breaking physiological dormancy and initiating germination. Therefore, the V. sibiricum seeds showed non-deep physiological dormancy (PD). Previous research, which determined seed dormancy classes, revealed that Veronica taxa have PD, morphological (MD), or morphophysiological seed dormancy (MPD). The differences in the seed dormancy classes in the Veronicastrum-Veronica clade suggested that seed dormancy traits had diverged. The results provide important data for the evolutionary ecological studies of seed dormancy and seed-based mass propagation of V. sibiricum.

Problems and prospects of introduction and distribution of Allium obliquum L. in Ukraine

Aim. To investigate the distribution of a rare perennial species in Ukraine — Allium obliquum L. and prospects for the development of the plant as a vegetable and ornamental crop. Methods. Materials for the analysis of the state of distribution in the area of origin, problems and prospects of development of the species Allium obliquum L. in Ukraine have been studied and generalized based on the results of processing scientific sources of literature. On the basis of own researches of a species, the forecast concerning prospects of introduction of a species in domestic vegetable growing, and also as an ornamental plant, is made; the necessary scientific, practical and organizational measures are identified. Results. Non-traditional species of perennial bulbous plants have significant potential for development in the vegetable growing. These include Allium obliquum L. — a rare relict species of onion in Ukraine with a disjunctive range, now its status — endangered, listed in the Red Book of Ukraine, which has decorative and nutritional value. When used as a vegetable, Allium obliquum L. can grow in one place for 10–15 years. Development of this species in vegetable growing in Ukraine is possible through the introduction into horticulture and ornamental floriculture based on the results of a comprehensive and large-scale study of the species in nature and culture, a long process of acclimatization, reacclimatization and reintroduction. Conclusions. An important stage of the breeding process is the introduction and mobilization of genetic resources to form a collection of source material Allium obliquum L. of various ecological and geographical origins, selection of sources and donors of economically valuable traits and properties, their involvement in the breeding process. An urgent task in Ukraine is the development of methodological and regulatory documentation, which is necessary both at the stage of scientific and technical examination of potentially created varieties, and in the production of seeds and marketable products.

The Bacterial Wilt Reservoir Host Solanum dulcamara Shows Resistance to Ralstonia solanacearum Infection

Ralstonia solanacearum causes bacterial wilt, a devastating plant disease, responsible for serious losses on many crop plants. R. solanacearum phylotype II-B1 strains have caused important outbreaks in temperate regions, where the pathogen has been identified inside asymptomatic bittersweet (Solanum dulcamara) plants near rivers and in potato fields. S. dulcamara is a perennial species described as a reservoir host where R. solanacearum can overwinter, but their interaction remains uncharacterised. In this study, we have systematically analysed R. solanacearum infection in S. dulcamara, dissecting the behaviour of this plant compared with susceptible hosts such as tomato cv. Marmande, for which the interaction is well described. Compared with susceptible tomatoes, S. dulcamara plants (i) show delayed symptomatology and bacterial progression, (ii) restrict bacterial movement inside and between xylem vessels, (iii) limit bacterial root colonisation, and (iv) show constitutively higher lignification in the stem. Taken together, these results demonstrate that S. dulcamara behaves as partially resistant to bacterial wilt, a property that is enhanced at lower temperatures. This study proves that tolerance (i.e., the capacity to reduce the negative effects of infection) is not required for a wild plant to act as a reservoir host. We propose that inherent resistance (impediment to colonisation) and a perennial habit enable bittersweet plants to behave as reservoirs for R. solanacearum.

Predicting the Potential Distribution of Perennial Plant Coptis chinensis Franch. in China under Multiple Climate Change Scenarios

Coptis chinensis Franch. (Ranales: Ranunculaceae) is a perennial species with high medicinal value. Predicting the potentially geographical distribution patterns of C. chinensis against the background of climate change can facilitate its protection and sustainable utilization. This study employed the optimized maximum entropy model to predict the distribution patterns and changes in potentially suitable C. chinensis’ regions in China under multiple climate change scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5) across different time periods (1970–2000, 2050s, 2070s, and 2090s). The results revealed that the currently potentially suitable regions of C. chinensis span an area of 120.47 × 104 km2, which accounts for 12.54% of China’s territory. Among these areas, the low, moderate, and highly suitable regions are 80.10 × 104 km2, 37.16 × 104 km2, and 3.21 × 104 km2, respectively. The highly suitable regions are primarily distributed in Chongqing, Guizhou, Zhejiang, Hubei, and Hunan Provinces. Over time, the potentially suitable regions of C. chinensis are predicted to shrink. Furthermore, our study revealed that the relatively low impact areas of C. chinensis were mainly distributed in Yunnan, Guizhou, Hubei, Chongqing, and other Provinces. Centroid transfer analysis indicated that except for SSP1-2.6, the center of the potentially suitable region of C. chinensis showed a trend of gradual transfer to the northwest and high-altitude areas.

Non-deep physiological dormancy in seeds of Euphorbia jolkinii Boiss. native to Korea

Background Euphorbia jolkinii Boiss. is a perennial species native to Jeju Island and the southern coastal area of Korea. Particularly on Jeju Island, the yellow flowers of E. jolkinii Boiss. have a high ornamental value because of their contrast with basalt. This study was conducted to investigate the effects of different temperatures (5, 15, 20, and 25 °C) and gibberellic acid (GA3) concentrations (0, 10, 100, or 1000 mg/L) on seed dormancy and germination of E. jolkinii. In addition, we classified the seed dormancy type and compared types with those of other species in the same genus. Results The number of seeds with viable embryos and endosperms was approximately 66%. The final germination percentages at 5, 15, 20, and 25 °C were 51.7%, 83.5%, 2.6%, and 0.0%, respectively. In GA3 concentration experiments, the final germination percentages of 0, 10, 100, and 1000 mg/L were 83.5%, 91.7%, 79.1%, and 83.4%, respectively, at 15 °C conditions, and 0.0%, 6.9%, 13.2%, and 27.3%, respectively, at 25 °C. Conclusions Germination improved at temperatures of 15 °C or lower. Furthermore, GA3 treatment effectively reduced germination times. Thus, the seeds of E. jolkinni were classified as having non-deep physiological dormancy.

Transposition and duplication of MADS-domain transcription factor genes in annual and perennial Arabis species modulates flowering

The timing of reproduction is an adaptive trait in many organisms. In plants, the timing, duration, and intensity of flowering differ between annual and perennial species. To identify interspecies variation in these traits, we studied introgression lines derived from hybridization of annual and perennial species, Arabis montbretiana and Arabis alpina, respectively. Recombination mapping identified two tandem A. montbretiana genes encoding MADS-domain transcription factors that confer extreme late flowering on A. alpina. These genes are related to the MADS AFFECTING FLOWERING (MAF) cluster of floral repressors of other Brassicaceae species and were named A. montbretiana (Am) MAF-RELATED (MAR) genes. AmMAR1 but not AmMAR2 prevented floral induction at the shoot apex of A. alpina, strongly enhancing the effect of the MAF cluster, and MAR1 is absent from the genomes of all A. alpina accessions analyzed. Exposure of plants to cold (vernalization) represses AmMAR1 transcription and overcomes its inhibition of flowering. Assembly of the tandem arrays of MAR and MAF genes of six A. alpina accessions and three related species using PacBio long-sequence reads demonstrated that the MARs arose within the Arabis genus by interchromosomal transposition of a MAF1-like gene followed by tandem duplication. Time-resolved comparative RNA-sequencing (RNA-seq) suggested that AmMAR1 may be retained in A. montbretiana to enhance the effect of the AmMAF cluster and extend the duration of vernalization required for flowering. Our results demonstrate that MAF genes transposed independently in different Brassicaceae lineages and suggest that they were retained to modulate adaptive flowering responses that differ even among closely related species.

The morphological and biological characteristics of the specimens from Monarda didyma

The plants of the genus Monarda of the family Lamiaceae are little known in our country. The species Monarda didyma is mainly distributed. It is used in landscaping as a perennial ornamental crop. In addition to its original blossoms, it has a pleasant aroma combining the aromas of bergamot, lemon and mint, due to the essential oils contained in the leaves, blossoms and stems of the plant. The Institute of Ornamental and Medicinal Plants - Sofia has a perennial species collection in which the genus Monarda is represendted by 32 genotypes of the Monarda didyma species. The plants are characterized by different habit, color and shape of the blossoms. During the phenological observations it was established that in the Sofia field region the Мonarda vegetation begins in the beginning of March and ends in the beginning of October. The flowering period in almost all samples covers the months of June to August, with mass flowering in the beginning of July. Biometric measurements show differences in the size of the tufts formed, the size of the leaves and the flowers. After analyzes, genotypes with emphasized decorative qualities were separated, which will be used to diversify the range of seedlings in the Monarda didyma type offered on the market.

Efficiency of graft-transmitted JcFT for floral induction in woody perennial species of the Jatropha genus depends on transport distance

Flowering Locus T (FT) promotes flowering by integrating six genetic pathways. In Arabidopsis, the FT protein is transported from leaves to shoot apices and induces flowering. However, contradictory conclusions about floral induction via graft-transmitted FT in trees were reported in previous studies. We obtained extremely early-flowering transgenic woody Jatropha curcas by overexpression of J. curcas FT using Arabidopsis thaliana SUC2 promoter (SUC2:JcFT) and non-flowering transgenic J. curcas by RNA interference (RNAi), which were used to investigate the function of graft-transmitted JcFT in floral induction in woody perennials. Scions from five wild-type species of the Jatropha genus and from JcFT-RNAi transgenic J. curcas were grafted onto SUC2:JcFT rootstocks. Most grafted plants produced flowers in 1–2 months, and the flowering percentage and frequency of various grafted plants decreased with increasing scion length. Consistently, FT protein abundance in scions also decreased with increasing distance from graft junctions to the buds. These findings suggest that FT proteins can be transmitted by grafting and can induce the floral transition in woody perennials, and the efficiency of graft-transmitted JcFT for floral induction depends on the scion length, which may help explain previous seemingly contradictory observations regarding floral induction via graft-transmitted FT in trees.

MƏRKƏZİ KİÇİK QAFQAZ (AZƏRBAYCAN HÜDUDLARINDA) FLORASININ QİDA BİTKİLƏRİNİN TAKSONOMİK TƏRKİBİ VƏ BİOEKOLOJİ XÜSUSİYYƏTLƏRİ

The article presents the species composition, bioecological features and the possibility of using of food plants in the flora of the Central Part of Lesser Caucasus (CLC) within Azerbaijan. During the taxonomic analysis of the species composition of food plants, 209 species belonging to 157 genera and 59 families were identified. According to the life forms among identified species 95 were perennials and 43 were annual herb plants. Trees are represented by 26 species, shrubs by 24 species, biannual herb plants by 21 species. In relation to moisture, six ecological types were identified. Among them mesophytes predominate with 91 species and xerophytes with 74 species. Mesoxerophytes include 23 species, xeromesophytes 20 species and mesohygrophytes one species. It was found that of the identified food plants, leaves of about 50 species are used both in fresh and cooked form, leaves, roots, rhizomes, bulbs, and fruits of 42 species in fresh, salted and cooked form and 30 species for obtaining of oil. Keywords: annual, ecological groups, life forms, mezophytes, perennial, species composition, xerophytes