Complete Chloroplast Genome Sequence of Chinese Lacquer Tree (Toxicodendron vernicifluum, Anacardiaceae) and Its Phylogenetic Significance.

Chinese lacquer tree (Toxicodendron vernicifluum) is an important commercial arbor species widely cultivated in East Asia for producing highly durable lacquer. Here, we sequenced and analyzed the complete chloroplast (cp) genome of T. vernicifluum and reconstructed the phylogeny of Sapindales based on 52 cp genomes of six families. The plastome of T. vernicifluum is 159,571 bp in length, including a pair of inverted repeats (IRs) of 26,511 bp, separated by a large single-copy (LSC) region of 87,475 bp and a small single-copy (SSC) region of 19,074 bp. A total of 126 genes were identified, of which 81 are protein-coding genes, 37 are transfer RNA genes, and eight are ribosomal RNA genes. Forty-nine mononucleotide microsatellites, one dinucleotide microsatellite, two complex microsatellites, and 49 long repeats were determined. Structural differences such as inversion variation in LSC and gene loss in IR were detected across cp genomes of the six genera in Anacardiaceae. Phylogenetic analyses revealed that the genus Toxicodendron is closely related to Pistacia and Rhus. The phylogenetic relationships of the six families in Sapindales were well resolved. Overall, this study providing complete cp genome resources will be beneficial for determining potential molecular markers and evolutionary patterns of T. vernicifluum and its closely related species.

The importance of the North Atlantic land bridges and eastern Asia in the post-Boreotropical biogeography of the Northern Hemisphere as revealed from the poison ivy genus (Toxicodendron, Anacardiaceae).

The Northern Hemisphere was widely covered by a tropical flora (i.e., the Boretropical flora) in the Eocene and the evaluation of plant diversifications in the post-Boreotropical era has become an important challenge to understanding the modern biogeographic complexity in this vast region. Toxicodendron or the poison ivy genus of the sumac family has a temperate to tropical distribution in Asia and North America and can serve as an excellent model for investigating the evolution of the post-Boreotropical biogeographic complexity. Molecular age estimates were calculated using a Bayesian approach with sampling covering the taxonomic diversity and biogeographic distributions within the genus, and sequence data from three nuclear DNA (ITS, ETS, NIA-i3) and two chloroplast (ndhF, trnL-F) regions, combined with calibrations from three fossil records. Ancestral areas were reconstructed using RASP and BioGeoBears. Toxicodendron is estimated to have a Boreotropical origin in the New World in the late Eocene at 37.68 Ma. It then diversified into a subtropical-temperate and a tropical lineage, followed by migrating into eastern Asia via the North Atlantic land bridges in the Oligocene to early Miocene. Two tropical migration events during the Miocene are identified between continental Asia and SE Asia or New Guinea around 20.91 Ma and 14.33 Ma, respectively. Results from this study highlight the importance of the North Atlantic land bridges and eastern Asia in the post-Boreotopical plant divergences in the Northern Hemisphere, especially when biogeographic exchanges between North and South America were limited.

Emergency: Treating poison ivy, oak, and sumac.

Still no magic bullet-but a range of options, old and new.

[Genetic evaluation of Toxicodendron vernicifluum cultivars using amplified fragment length polymorphism markers].

Accurate identification of Toxicodendron vernicifluum varieties and understanding their genetic relationships are essential for the improved varieties selection. In this study, Amplified fragment length polymorphism (AFLP) markers was used to evaluate the genetic resources of nine Toxicodendron vernicifluum cultivars from Shaanxi. Eight pairs of AFLP primers with Mse I fluorescent labeled were screened from EcoR I /Mse I primer combinations. Different pair of primers differs widely to detect genetic polymorphism of Toxicodendron vernicifluum. The polymorphic bands detected by each pair of primers ranged from 242 to 622 with average value of 350.88. Eight pairs of AFLP primers produced 4463 bands in total. Among them, 2807 bands (62.64%) were polymorphic. genetic similarity coefficient (SC) among all cultivars varied from 0.673 to 0.833, which further verified that only a little genetic diversity existed among the cultivars. It was the first time that AFLP technique was applied to identify Toxicodendron vernicifluum cultivars. The study suggested that AFLP technique is a useful tool for individual identification of Toxicodendron vernicifluum cultivars and could be applied to the Toxicodendron vernicifluum' fingerprinting work in China.

Toxicodendron dermatitis: poison ivy, oak, and sumac.

Allergic contact dermatitis caused by the Toxicodendron (formerly Rhus) species-poison ivy, poison oak, and poison sumac-affects millions of North Americans every year. In certain outdoor occupations, for example, agriculture and forestry, as well as among many outdoor enthusiasts, Toxicodendron dermatitis presents a significant hazard. This review considers the epidemiology, identification, immunochemistry, pathophysiology, clinical features, treatment, and prevention of this common dermatologic problem. Recent research in prevention is emphasized, and resources to help in the identification of plants are provided in the bibliography. The literature was searched using a MEDLINE query for "Toxicodendron dermatitis", and the identified article bibliographies were searched as well.

Is it, or isn't it? Poison ivy look-a-likes.

Poison ivy causes more allergic contact dermatitis (ACD) than any other cause. Although physicians rightfully focus on the treatment of the dermatitis, prevention will be aided by recognition of the foreboding plant. Likewise, many other plants can masquerade as poison ivy and cause one to needlessly curtail his or her activities because of fear of a bad reaction. The most common poison ivy pretenders in the United States are discussed, and distinguishing plant characteristics are highlighted.

Recognizing the Toxicodendrons (poison ivy, poison oak, and poison sumac).

Poison ivy, poison oak, and poison sumac are now classified in the genus Toxicodendron which is readily distinguished from Rhus. In the United States, there are two species of poison oak, Toxicodendron diversilobum (western poison oak) and Toxicodendron toxicarium (eastern poison oak). There are also two species of poison ivy, Toxicodendron rydbergii, a nonclimbing subshrub, and Toxicodendron radicans, which may be either a shrub or a climbing vine. There are nine subspecies of T. radicans, six of which are found in the United States. One species of poison sumac, Toxicodendron vernix, occurs in the United States. Distinguishing features of these plants and characteristics that separate Toxicodendron from Rhus are outlined in the text and illustrated in color plates.