Leaf_vegetable fern

Description

Diplazium esculentum, the vegetable fern, is an edible fern found throughout Asia and Oceania. It is probably the most commonly consumed fern. This plant is a large perennial fern with ascending rhizome of about 50 cm high and covered with short rufous scales of about 1 mm long. The plant is bipinnate with long brownish petioles, and the petiole base is black and covered with short scales. The frond can reach 1.5 m in length, and the pinnae is about 8 cm long and 2 cm wide. It is known as pakô ("wing") in the Philippines, pucuk paku and paku tanjung in Malaysia, sayur paku in Indonesia, dhekia in Assam "Dhenki Shaak in Bengali ", paloi saag Sylheti, ningro in Nepali,dingkia in Boro and linguda in northern India, referring to the curled fronds. In Thailand it is known as phak khut. They may have mild amounts of fern toxins but no major toxic effects are recorded. Diplazium is a genus of ferns that specifically includes the approximately 400 known species of twinsorus ferns. The Greek root is diplazein meaning double: the indusia in this genus lie on both sides of the vein. These ferns were earlier considered part of either the Athyriaceae, Dryopteridaceae, Aspleniaceae, or Polypodiaceae families or recognized as belonging to their own taxonomic family. The Pteridophyte Phylogeny Group classification of 2016 (PPG I) places the genus in the Athyriaceae. The taxonomy of the genus is difficult and poorly known, and by 2009 has never been the subject of a complete monographic study. Their distribution is pantropical, with a few species extending into temperate areas. The rhizome of the genus Diplazium varies from creeping to erect, and is scaly. Its fronds are deciduous or evergreen, are trophopodic and are either monomorphic or weakly dimorphic. The stipe is green, deeply grooved from above, and is either scaly or glabrous. It always has two lunate vascular bundles. The blades are either singular or in sets of two and are entirely pinnate, range from oblong-lanceolate to deltate, and from herbaceous to papery. It has linear basal sori that are paired back-to-back on the same vein. The indusium is linear and persistent, and the sporangia are brownish. Some common species include Diplazium hymenodes, the peacock fern; Diplazium esculentum, the vegetable fern; Diplazium molokaiense, the Molokai twinsorus fern; and Diplazium lonchophyllum, the lance-leaved glade fern.