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Background: Delphinium L. represents a taxonomically intricate genus of significant phylogenetic and economic importance in Ranunculaceae. Despite the existence of few chloroplast genome datasets, a comprehensive understanding of genome structures and selective pressures within the genus remains unknown. Furthermore, several taxa in this genus are exclusively found in Xinjiang, China, a region renowned for its distribution and diversity of Chinese and Central Asian Delphinium species. Therefore, investigating the features of chloroplast genomes in this area will provide valuable insights into the evolutionary processes and phylogenetic relationships of the genus., Results: In this study, the eight newly completed chloroplast genomes are examined, ranging in length from 153,979 bp to 154,284 bp. Alongside these, analysing six previously reported taxa re-annotated in Delphinium, 111 unique genes are identified across all samples. Genome structure, distributions of simple sequence repeats and short dispersed repeats, as well as gene content are similar among these Delphinium taxa. Nine hypervariable intergenic spacers and protein coding regions, including ndhF-trnL (TAG) , rpl16-intron, rpl33, rps15, rps18, trnK (TTT) -trnQ (TTG) , trnP (TGG) -psaJ, trnT (GGT) -psbD and ycf1, are identified among 13 perennial Delphinium. Selective pressure and codon usage bias of all the plastid genes are performed within 14 Delphinium taxa. Phylogenetic analysis based on 14 Delphinium plastomes, alongside two Aconitum (Ranunculaceae) species serving as outgroup taxa, reveals the monophyletic nature of Delphinium. Our findings further discern Delphinium into two distinct clades: perennial species (clade I) and annual species (clade II). In addition, compared with the nrDNA ITS topology, cytological data and morphological characters, D. mollifolium and D. maackianum showed potential involvement in hybridization or polyploidization processes. Excluding these two species, the perennial Delphinium (clade I) exhibits a stronger consistency with the morphology-based system that utilized seed morphology., Conclusion: This study represents the first comprehensive analysis of plastomic variations among Delphinium taxa, based on the examination of 14 complete plastomes. The chloroplast genome structure of Delphinium is similar to other angiosperms and possesses the typical quadripartite structure with the conserved genome arrangement and gene features. In addition, the variation of non-coding regions is larger than coding regions of the chloroplast genome. Through DNA sequence divergence across Delphinium plastomes and subsequent phylogenomic analyses ndhF-trnL (TAG) and ycf1 are identified as promising molecular markers. These highly variable loci held significant potential for future phylogenetic and phylogeographic studies on Delphinium. Our phylogenomic analyses based on the whole plastomes, concatenation of 132 unique intergenic spacer regions, concatenation of 77 unique protein-coding genes and nrDNA ITS, all support the monophyly of Delphinium and perennial taxa clusters together into one clade within this genus. These findings provide crucial data for systematic, phylogenomic and evolutionary research in the genus for future studies., (© 2024. The Author(s).)

The study of intracellular gene transfer may allow for the detection of interesting evolutionary processes such as ancient polyploidization. We compared 24 plastid genomes (plastomes) from tribe Delphinieae, one from tribe Nigelleae and one from tribe Ranunculeae, including five newly sequenced genomes. The functional transfers of the plastids rpl32 and rps16 to the nucleus in tribe Delphinieae were identified. Unexpectedly, we discovered multiple divergent copies of the nuclear-encoded plastid rpl32 in the genus Aconitum. Phylogenetic and synonymous substitution rate analyses revealed that the nuclear-encoded plastid rpl32 underwent two major duplication events. These ancient gene duplication events probably occurred via multiple polyploidization events in Aconitum between 11.9 and 24.7 Mya. Furthermore, our sequence rate analysis indicated that the eight plastid-encoded rpl subunits in Aconitum had a significantly accelerated evolutionary rate compared to those in other genera, suggesting that highly divergent paralogs targeted to the plastid may contribute to an elevated rate of evolution in plastid rpl genes. In addition, heteroplasmy of the plastid matK from two Aconitum species suggested the existence of potentially functional plastid maturases in its plastome. Our results provide insight into the evolutionary history of the tribe Delphinieae.

In present research, micromorphological characters of the genus Delphinium L. (sensu lato) Ranunculaceae seeds and fruits were studied using microscopic techniques. A total of 37 species were studied using light (LM) and scanning electron microscopy (SEM) to evaluate seeds and fruits micromorphological characteristics for the taxonomic identification and species relationship in the genus. For each taxon, 33 characters were observed and studied. All characters were analyzed using MVSP software and UPGMA method by using dissimilarity index (average taxonomic distance). Considerable differences were observed in trichomes shape of fruit and seed color features. The results revealed that all studied taxa are separated into three clades. The first clade consists of D. pallidiflorum and D. semibarbatum, which have black seed and two types of glandular and crispate trichomes in fruit. The second clade consists of D. speciosum, D. szowitsianum, D. dasystachyson, D. aquilegifolium, D. ursinum, C. trigonelloides, and C. camptocarpa, which had a brown color seeds, two types of glandular and villous trichomes on fruits also have been observed. The remaining species were classified as third clade having various colors including yellow, black, and brown color seeds, the trichome shapes included one of the following forms strigose, villous, trichomes less, glandular, hooked, and crispate trichomes in fruits. The aim of the present study is to use micromorphological characters of seeds and fruits for the taxonomic identification and species delimitation in the genus Delphinium., (© 2019 Wiley Periodicals, Inc.)

The use of quality control tool for authentication of Jadwar (Delphinium denudatum Wall. ex Hook.f. & Thomson), a folk herbal drug used for the treatment of different ailments, was studied. People face problems of adulteration for this drug at global, regional, national and local levels. Two different plant species are commercially marketed in the Indo-Pak Subcontinent under the same trade name of Jadwar. One is D. denudatum Wall. ex Hook.f. & Thomson and the other is Aconitum heterophyllum Wall. ex Royle. To focus on this problem, a marketable available drug sample of Jadwar was authenticated by using basic microscopy tools (LM) and advanced chemo-taxonomic markers. Authentication, quality and standardization of this drug was achieved using morphology, organoleptography, UV and IR analyses, scanning electron microscopy of pollen and anatomical investigations. The techniques used for authentication marked the clear difference between the studied plants. Microscopic studies, chemotaxonomic investigation and other techniques used in this project provided the basis for the authentication of this species., (© 2019 Wiley Periodicals, Inc.)

Larkspurs (Delphinium spp.) are a serious toxic plant problem for cattle in western North America. There are two chemotypes of D. occidentale, a more toxic and a less toxic chemotype. The objective of this study was to evaluate the acute toxicity of the less toxic chemotype when administered in multiple doses to cattle. These results suggest that cattle could consume enough of the less toxic chemotype to be poisoned in a range setting., (Published by Elsevier Ltd.)

Objective: To compare the toxic effects of a Delphinium occidentale chemotype containing N-(methylsuccinimido) anthranoyllycoctonine (MSAL)-type alkaloids and a D occidentale chemotype lacking MSAL-type alkaloids in mice and cattle., Animals: 225 male Swiss Webster mice and 11 Black Angus steers., Procedures: 4 collections of larkspur containing MSAL-type alkaloids and 4 collections of larkspur lacking MSAL-type alkaloids were used. From each collection, total alkaloid extracts (0.05 to 0.20 mL) were administered via tail-vein injection in 27 to 29 mice. Dried, finely ground plant material from 1 collection with and 1 collection without MSAL-type alkaloids (doses equivalent to 37.6 mg of total alkaloids/kg) were each administered to 8 cattle via oral gavage in a crossover experiment; 3 cattle received a single dose equivalent to 150.4 mg of total alkaloids/kg (no MSAL-type alkaloids). In mice, clinical effects were monitored; in cattle, heart rate was monitored before (baseline) and 24 hours after treatment. At the 24-hour time point, cattle were exercised as a measure of muscle weakness., Results: In mice, mean LD(50) associated with alkaloid extracts prepared from plants that did or did not contain MSAL-type alkaloids was 2.3 and 54.2 mg/kg, respectively. In cattle at 24 hours after treatment, plant material containing MSAL-type alkaloids significantly increased heart rate from baseline and was associated with exercise-induced collapse; plant material lacking MSAL-type alkaloids had no similar effects., Conclusions and Clinical Relevance: Taxonomic classification of D occidentale alone was not a good indicator of the toxic risk to grazing cattle.

To clarify the relationships of flower senescence, especially sepal abscission, and ethylene receptor gene expression in different flower parts, we isolated two cDNAs encoding ethylene receptors Dl-ERS1-3 and Dl-ERS2 from Delphinium flowers. Deduced polypeptides possessed no response regulator domain, indicating that they belong to a family of ethylene response sensor (ERS) ethylene receptors. Dl-ERS1-3 and Dl-ERS2 exhibited constitutive levels during flower senescence. Exogenous ethylene increased transcript levels in sepals, which are influenced by ethylene but not in gynoecia and receptacles, which produce ethylene. It was suggested that expression of ethylene receptor genes under ethylene exposure was differentially regulated in each organ of the flower.