Encyclopedia

Pellea

Pellea (Pellaea) - a genus of ferns of the Pteris family (Pteridaceae). Includes 50 types.

The name of the genus comes from the Greek word πελλος (pellos), which means "dark," and refers to the coloration of plant stems.

Pelleys are widespread in the southwestern United States and Mexico, South America, Central and East Africa, a small number in Asia, Australia, and the Pacific Islands. In the north they reach Canada, and in the south to Chile and New Zealand. Pellea belongs to the subfamily of Heilantoid ferns - xerophilous plants, inhabitants of dry places that can withstand prolonged drought. They grow mainly in arid areas, with alternating dry and wet seasons throughout the year, but practically do not occur in places where it is constantly dry. They can be found on rocks, in canyons, on rocky slopes, on the walls of houses and trees, in holes and cracks where some soil accumulates.

The genus Pellea is a diverse, poorly defined collection of ferns adapted to arid conditions and is polyphyletic. The similarity of the external appearance is determined not so much by the common ancestor as by the growing conditions.

The stems, modified into creeping rhizomes, are compact or rather long, usually branched, covered with scales, brown or often bi-colored (with a dark middle and lighter edges), grow deeply into cracks in rocks.

Leaves are pinnate or multiply pinnate, monomorphic or slightly dimorphic, collected in a rosette or widely spaced along the stem, 2-100 cm long, leathery above, usually smooth, with a whitish or yellowish bloom below. The leaf rachis (central part) is straight or curved in a zigzag pattern. Leaf segments often have short petioles.

Like all ferns, pellets go through two stages in their development - sporophyte and gametophyte. Sporophyte is a common fern. In the sporangia, located on the underside of its leaves, spores are formed, from which a small plant, gametophyte, grows later. Sex cells are already formed on it, in the aquatic environment they merge, and fertilization occurs, a sporophyte grows.

The sporangia in pellets are arranged in a line along the edges of the leaves and are protected from above by their curved edges.

As another adaptation to arid conditions, apomictic reproduction is widespread in pellets - their sporophytes often grow from the somatic cells of the gametophyte, bypassing the fertilization process. This makes them independent of the availability of free water, which is necessary for gametes to meet. In pelles, interspecific hybrids and populations within a species are widely found, differing in the number of chromosomes - in addition to the usual diploids (2n), there are triploids (3n), tetraploids (4n), and even pentaploids (5n), which also reproduce using apomixy. It should be noted that gametophytes and spores retain their viability even after prolonged drying.

Beautiful and unpretentious, pellets are very popular and have been grown in greenhouses in England and America since the time of Queen Victoria. They are excellent plants for shady garden areas in warm climates, and several species are cultivated as indoor plants.

Round-leaved pellet (Pellaea rotundifolia)

Round-leaved pellet (Pellaea rotundifolia) - a small evergreen fern with a creeping rhizome, from which feathery curving leaves extend, growing up to 45 cm long. The leaf petioles are brown, covered with dark scales. On both sides of the rachis, which acquires a dark red color with age, there are small, round (about 2 cm in diameter), slightly glossy, dark green segments on short petioles in pairs (up to 30). Native to New Zealand, Australia and Norfolk Island, where it grows on limestone cliffs, cracks in rocks and damp open forest areas, but is sometimes found in drier forest areas. This type is most common in indoor floriculture.

Sickle pellea (Pellaea falcata) widespread in Eastern Australia and New Zealand, where it is often found on rocky coasts and in low shrubs, in eucalyptus forests. Fries up to 1 m long, feathery. Segments are oblong, about 4-5 cm long and 1.5-2 cm wide, arranged on rachis in pairs, glossy and green above, paler below. Petioles and rachis are dark brown, densely covered with scales.

Sickle pellets and round-leaved pellets in natural conditions give stable, apomictically multiplying, intermediate forms. On the basis of genetic studies, this species has been abolished.

Dwarf pellet (Pellaea nana), also known as Pellaea falcata var. nana, grows in tropical and eucalyptus forests in Eastern Australia, more often on rocks or large boulders. Vayi 20-50cm long, feathery. Leaves in the amount of 25-65 are arranged in pairs on both sides of the rachis, oblong or narrow-oblong in shape, dark green above and lighter below. This species is absent in the new classification.

Pellea dark purple (Pellaea atropurpurea) originally from North and Central America. It grows in the cracks of dry limestone rocks, on rocky slopes.

This fern forms a cluster of widely curving, double-pinnate leaves. The petiole and leaf rachis are purple, and the leaf blade is bluish-gray. The upper segments are long, narrow and undivided, while the lower ones consist of 3-15 leaflets. Spore-bearing leaves are longer and more strongly divided.

Analysis of the chromosomes showed that it is an abnormal autotriploid (3n). Probably descended from a diploid taxon that has not yet been discovered. In nature, dark purple pellets are capable of hybridizing with P. glabella, P. wrightiana, P. truncata, and often such plants have their own specific names, they reproduce apomictically.

Pellaea atropurpurea differs from all these hybrids in the presence of dense pubescence on the rachis, and in larger terminal segments.

Pellea nude (Pellaea glabella) - native to North America, grows on well weathered limestone. Leaves are linear, up to 35 cm, pinnate or double pinnate, petioles are brown, glabrous. For a long time, this species was considered a reduced form or variety of dark purple pellets. In nature, there are both diploid plants that reproduce sexually, and tetraploid plants that reproduce apogamously.

It is possible to distinguish naked pelea from dark purple pellea by the absence of hairs on the end segments of the leaves.

Pelleus ovoid(Pellaea ovata) widespread in the southern United States, Mexico, Central and South America. Lives on rocky slopes.

Stems are creeping, horizontal, thin, covered with two-colored scales. Leaves are monomorphic, 15-100 cm long and 5-25 cm wide, thrice-pinnate, with large heart-shaped light green leaves. Rachises of leaves are strongly curved.

Pellea spear-shaped (Pellaea hastate) originally from Africa, the Mascarene Islands and Madagascar. The stem is creeping, the leaves are collected in a basal rosette, with long red-brown petioles. The leaf blades are triangular, about 60 cm long and 30 cm wide, double- or triple-pinnate. Segments are broadly lanceolate or triangular, asymmetric.

Pellea green (Pellaea viridis) grows in Africa, India, on some islands of the Pacific Ocean. The rhizome is short, creeping, 5 mm in diameter, covered with brown scales. The leaves are arched, dark green. Petioles are dark brown, about 40 cm long. The leaf blade is lanceolate or ovate, about 50 cm long and 24 cm wide, mainly double- and triple-pinnate. The lower segments are the largest. Leaflets are oblong-lanceolate, rounded or sharp at the apices, cordate at the base.

About cultivation - in the article Pellea: an unpretentious indoor fern.

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