Recently discovered As-hyperaccumulator ferns hold promise for phytoremediation of As-polluted soils. We investigated changes in the rhizosphere characteristics of Pteris vittata (Chinese Brake fern) relevant for its use in phytoextraction. Plants were grown in rhizoboxes filled with soil containing 2270 mg kg(-1) As. Dissolved organic carbon (DOC) concentrations in rhizosphere soil solution we...

A field study was conducted to determine the efficiency of Chinese brake fern (Pteris vittata L.), an arsenic hyperaccumulator, on removal of arsenic from soil at an arsenic-contaminated site. Chinese brake ferns were planted on a site previously used to treat wood with chromated copper arsenate (CCA). Arsenic concentrations in surface and profile soil samples were determined for 2000, 2001, an...

Fern-feeder aphids (Hemiptera: Aphididae) in China are represented by 13 species in 10 genera, including a new genus, Vietaphis gen nov., a new species, Vietaphis aliquantus sp nov., from Guizhou and Tibet on Plagiogyria japonicum, and a new subspecies, Amphorophora scabripes galba ssp nov., from Guizhou on Pentarhizidium intermedium. Two genera, Amphorophora Buckton and Idiopterus Davis, and f...

PREMISE OF THE STUDY California experienced severe drought between 2012 and 2016. During this period, we compared seasonal changes in tissue-water relations among eight fern species in the Santa Monica Mountains of southern California to elucidate differential mechanisms of drought survival and physiological performance during extreme water deficits. METHODS We monitored seasonal changes in w...

Chinese brake fern Pteris vittata hyperaccumulates arsenic in its fronds. In a study to identify brake fern cDNAs in arsenic resistance, we implicated a glutaredoxin, PvGRX5, because when expressed in Escherichia coli, it improved arsenic tolerance in recombinant bacteria. Here, we asked whether PvGRX5 transgenic expression would alter plant arsenic tolerance and metabolism. Two lines of Arabid...

Previous studies have shown that core leptosporangiates, the most species-rich group of extant ferns (monilophytes), have a distinct plastid genome (plastome) organization pattern from basal fern lineages. However, the details of genome structure transformation from ancestral ferns to core leptosporangiates remain unclear because of limited plastome data available. Here, we have determined the ...

To better understand the mechanisms of plant tolerance to high concentration of arsenic, we characterized two antioxidant enzymes, glutathione reductase (GR) and catalase (CAT), in the fronds of Pteris vittata, an arsenic-hyperaccumulating fern, and Pteris ensiformis, an arsenic-sensitive fern. The induction, activation and apparent kinetics of GR and CAT in the plants upon arsenic exposure wer...

Homosporous ferns have extremely high chromosome numbers relative to flowering plants, but the species with the lowest chromosome numbers show gene expression patterns typical of diploid organisms, suggesting that they may be diploidized ancient polyploids. To investigate the role of polyploidy in fern genome evolution, and to provide permanent genetic resources for this neglected group, we con...

Readers of Kalmiopsis were recently treated to a synopsis of taxonomic changes affecting flowering plants in Oregon (Chambers, 1992). The present article has been written to update readers on nomenclatural changes recently proposed for the seedless vascular plants, which include not only ferns, but also horsetails, club-mosses, and their relatives. Together these groups are often referred to as...

PREMISE OF THE STUDY Relationships of leaf size and shape (physiognomy) with climate have been well characterized for woody non-monocotyledonous angiosperms (dicots), allowing the development of models for estimating paleoclimate from fossil leaves. More recently, petiole width of seed plants has been shown to scale closely with leaf mass. By measuring petiole width and leaf area in fossils, le...