Pinopsida

Pinopsida first appeared in the Late Carboniferous, the more monotonous, mostly Walchia (vacci FIR), the early Mesozoic evolution of world class pinopsida most strongly to the late Jurassic or early Cretaceous period, seems to have reached its peak, The Paleozoic Era Type pinopsida extinct is mainly attributable to the Voltziales (Voltaiales).
Pinopsida

Pinopsida Feature introduction

 Pinopsida Pinopsida
Evergreen or Simple leaf The tree trunk, developed with telome origin of leaf, leaf shape, linear lanceolate, Chengzhen, chaetic or flake shape,
Most of the single pulse, with a few Parallel vein . Leaves in the branches of the general arrangement is spiral or pseudo two columns, and a few decussate or whorled, also some are two columns. Leaves usually thicker Cuticle Small, epidermal cells, with thick wall and deep hole. Pinopsida generally Monoecism . Female flowers and trees with harsh as female similar characteristics, is a female compound structure by nutrition scales and stipitate ovule Composition, long in the supporting sheet of axilla. Different kinds of fruit Linyou different sources, some from the chaff, some from the nutrition scales, some from the fusion support sheet and nutrition scales. Seeds with hard seed coat. Secondary xylem from Tracheid Composition, usually with resin and resin cell.
Pinopsida plant Sperm cells No cilia, this trait in gymnosperms System development A Cycadopsida and Ginkgopsida Evolution.

Pinopsida The mode of reproduction

Pinopsida divided into the reproductive organs of plants Male flowers and Female flowers Two. Male ball flower pollen; female flowers
 Ovule and megaspore Ovule and megaspore
In the wood scales
A seed. A young male cones of long scales Pollen sac That will produce a lot of pollen sac. Pollen size is about 1/50000 to 1/5000 cm, weight is very light. When the pollination season comes, the wind blows to the pollen from the male flowers on female cones. Some plants are pinopsida cones Monoecism In order to avoid geitonogamy, female, Male flowers Will mature at different times, and Female flowers Will grow in the higher branches of the top. In the mature pollen and female cones also ready for pollen preparation. Female flower ball will flake open, exposed ovule . There is a viscous liquid ovule, when the pollen arrived, just stuck, avoid flying away. After pollination, the female cone scales to close synthesis cone Cone, gradually dilated and keep green. In the cone, pollen will slowly seep into the ovule, and the formation of a tube. Through the root tubules, sperm and Egg cell With the completion of. Fertilization . In a few months or years, ovules develop into seeds. When Mature seeds After the scale open again, seeds can be spread by wind. Once the seed landed, bud root, grow into a new strain of gymnosperms.

Pinopsida life history

In the most common and most detailed study Pinaceae (Pinaceae). Pine (Pinus) as the representative, introduced as follows.

Pinopsida Sporogonium

 Pinopsida Pinopsida
Pine The Sporogonium Tall perennial Evergreen trees , Single axis Trunk erect, side branch Whorled, with long and short shoots. Dictyostele, by 90 - 95% Tracheid The resin composition, about 1%, Wood ray About 6%. Long branch students Scale leaf Axillary, endogenous Short branch Short, short branches, the top 1 beam needle-shaped leaves Usually, 2, 3 and 5 leaves per beam, the base often have film like Leaf sheath 8 - 12 (by Bud scales A) surrounded, with 1 or 2 leaves vascular bundle And a few Resin canal . Strobile Unisexual, monoecious. Microstrobil arranged like spikes, born in long branches at the base of the new year, the scales Leaf axil Give birth to. Each microstrobil has 1 vertical axis, vertical axis helical arrangement of Microstrobilus, back microsporophylls (abaxial) 1 for long Microsporangium . Microsporangium in The microspore mother cells After two times, successive divisions (one of which is Meiosis 4), the formation of microspore (pollen grains). microspore There are 2 layers of wall, outer wall protruding sideways into a balloon, can make the microspore floating in the air, easy to spread the wind.
Megastrobilus 1 was born in the year or several new branches near the top, the red or purple, then turn green and brown when mature. Megasporophyll The ball is composed of megasporophyll, megasporophylls is spirally arranged on the vertical axis, but they are not simple Sporophyl And it consists of two parts: the small sheet called Bracts Above; larger part called top hypertrophy Cone scales Also called. Fruit scales or Seed scales That is, ovuliferous scale megasporophyll, bracts is losing the reproductive capacity of megasporophyll. stay Pinaceae The genus of bracts and cone scales are completely separate from the base, each of the 1 cone scales on the adaxial surface with 2 ovule The ovule is composed of 1 layers, The beads are and Nucellus Which beads are surrounded by the formation of Micropyle . That is the Megasporangia 1, intermediate cells developed into large Sporocyte , after two consecutive division (one of which is Meiosis ), 4 Megaspore 1, arranged in a column called "chain Four split ". Usually only Point 1 end megaspore develops into a female Gametophyte The remaining 3, degradation.

Pinopsida Male gametophyte

male Gametophyte Is the 1 major structural decline, is composed of only a few cells.
microspore (single nuclear period Pollen ) is the first cell of male gametophyte, Microspore in Microsporangium Germination, cell division 2, the smaller is the first 1 Prothallus (cell Vegetative cells ), the other 1 big called embryogenic cells, embryogenic cell division is 2, namely second prothallial cells and The sperm is The original cell ( The central cell Antheridial initial), and then split into 2 forms Tube cell and germ cell . The mature male gametophyte of 4 cells: 2 degraded prothallial cells, 1 cells and 1 germ cell.

Pinopsida The female gametophyte

from Megaspore The development of A. Therefore, the megaspore is female Gametophyte The first cell in it Megasporangia ( Nucellus In germination, for free) Nuclear fission 16 - 32, with the formation of free nuclei, not formed cell wall . Around the female gametophyte with 1 thin cytoplasm, the central 1 big vacuole How many nuclear free, uniform distribution In the cytoplasm, when the winter comes, the female gametophyte enters dormancy. In the spring, the new female gamete weight began to perk up, swim
From the nucleus continue to divide, mainly the number of free nuclei increased significantly, increased volume. In the future Female gamete Begin to form cell wall free around the nucleus in vivo, then the micropylar end of some cells become swollen, The archegonium The original cell. After a series of original cell division, the formation of several archegonia, mature female gametophyte contains 2 - 7 archegonia and a large number of endosperm .

Pinopsida Pollination and fertilization

pollination
 Pine bonsai Pine bonsai
In late spring, this time Megaspore The leaf ball shaft slightly elongated, so young Bracts and Cone scales Slightly open. At the same time, Microsporangium Split a straight back, in the male gametophyte stage of pollen grains, spread by the wind, falling in the Micropyle over-flowing Pollination drops In the dry and with the liquid is drawn into the micropyle. Then the megastrobilus ovuliferous scale continued closure. male Gametophyte In reproduction cell division 2, the formation of 1 cells and 1 handle individual cells, and Tube cell Then begin to stretch and grow quickly Pollen tube . But it has not yet formed megaspore female gametophyte, the pollen tube entered Nucellus After a considerable distance, which temporarily stopped elongation, until the second year spring or summer The archegonium After the formation of differentiation, pollen tube to continue elongation, the body cell division to form 2 sperm ( Spermatium ). Fertilization Usually in the 13 months after pollination was carried out, namely pollination in the first year of the spring, summer fertilization in second years. When the megastrobilus had grown and reached or will reach its maximum volume, the archegonium has fully developed. When the pollen tube elongation to the archegonia, destruction of cervical cell arrival Egg cell At its apex, then rupture, 2 sperm cells and tube Stem cell All together into the egg cytoplasm, 1 of which with the function of sperm immediately to the central move, and close to the egg nucleus, and finally combined with the egg nucleus to form the zygote, this process is known Be fertilized .

Pinopsida seed

 The life history of the song The life history of the song
Pine The embryonic development The process, quite complex, with obvious phase, usually can be divided into Proembryonal Stage, embryo selection stage, embryo and organ Tissue differentiation Mature stage, embryo. But these phases are continuous development in order that is interacted.
1 proembryo stage: from the fertilized egg to the cell type of proembryo formation, after the division of free nuclei, cell wall formation and embryo formation.
The fertilized eggs of 3 successive free nuclear divisions, the formation of 8 free nuclei, 8 free nuclei in the The archegonium The base arranged in the upper and lower two layers, each layer of 4, cell wall In this form, but the upper upper 4 cells do not form cell wall, the cell cytoplasm and Egg cell Quality is called open the lower layer; the 4 is called the primary cell Embryo cell Layer. Then open the primary embryo cell layer each layer and then split into 4 layers of 1 times, respectively.
The upper layer, called the rosette, Suspensor Layer (primary suspensor layer) and germ cell layer, composition Proembryonal .
The 2 stage of embryo selection: The system development and Polyembryony Which is the main feature of this stage. 4 cell proembryo from top to bottom, the first layer (upper), early Absorption And shortly; second layer rosette layer disappeared after several split; third layer layer 4 cell suspensor, its primary suspensor, do not divide, but the elongation of fourth layers; Embryo cell Germ cell layer, continue to extend at the same time the suspensor cells, followed by embryo cells following division and elongation, called secondary suspensor, the suspensor and secondary suspensor (germ tube elongation) rapidly, forming multi winding the suspensor system. While the front layer cells of the embryo cells develop into embryo itself, but they do not consist of 1 embryos, and separated from each other in a vertical plane, each individual develops into the embryo, called polyembryony. Common Polyembryony There are two types: one is Simple polyembryony That is, in the same ovule There are more than 2 The archegonium The Egg cell At the same time, can be fertilized, and so on embryonic development In the early stage, can produce more than 2 Proembryonal ; another is cleavage polyembryony, 4 germ cells from 1 zygote formation, respectively developed into 4 embryos.
In the process of embryonic development, through embryo Choose, usually only 1 (rarely 2 or more) normal embryo differentiation and development, become a mature seed embryo.
Most conifers with archegonia of more than 2, so the simple polyembryony is a common occurrence
 Speciesis Speciesis
As for. Schizogenous Polyembryony That is limited to a few conifers of the genus visible.
3 embryos and organs Tissue differentiation Stage: The embryo become 1 cylinders of elongation in further development. The area near the axis of the cylinder (base) with Suspensor The system is mainly Transverse division Cells, slightly larger than the rule of the formation of root and then develop into the ranks. Root cap Organization; while in the far axis zone, cell division seems to be no particular direction, small cells and by these cells further differentiation, finally split Hypocotyl Germ, and cotyledon .
4 mature embryo: The mature embryo including Radicle , Hypocotyl (caulicle), embryo and cotyledon (usually 7 - 10). Surrounding the female embryo Gametophyte ( endosperm Finally) continue to grow. Nucellus Only a thin layer. The beads are develop into seed coat The seed coat, divided into 3 layers: the outer fleshy (developed), middle stone, lining paper.
Embryo, endosperm, seed coat structure.
Gymnosperms seed is composed of 3 generations, the embryo is new Sporophyte generation (2n); the endosperm is the female gametophyte generation (n); seed coat is old Sporogonium (2n). After fertilization, Megaspore The ball leaves continue to grow, Cone scales Lignification and become Seed scales That kind of scales expand exposed part of the top Scale Shield The middle scale shield, uplift or depression part Umbo Part of the epidermis, ovuliferous scale separated out to form seed appendages that spread wings, to wind. seed germination When the first root Micropyle Out of the seed coat, and quickly produced lateral root At the beginning, in the cotyledon in the seed, to absorb nutrients from the endosperm, with Hypocotyl The continuous development of cotyledon and cotyledon testa rupture, exposed, with the top of the stem growth, produce new plants.

Pinopsida Subordinate classification

Pinopsida plant is the largest number of taxa, the most widely distributed modern gymnosperms. Modern pinopsida plants have 44 genera, about 400 species,
Belonging to 4 families, i.e. Pinaceae , Taxodiaceae , Cupressaceae and Araucariaceae (Araucariaceae), and they are distributed in the north and south hemisphere in two, temperate northern hemisphere, Cold temperate zone The alpine zone is most common. China is the origin of the oldest pinopsida plant, but also Pine The most abundant plants and rich countries, endemic genera and species and The third century Relict plant, there are 3 families, 23 genera, about 150 species, most domestic species of gymnosperms, 1 classes of economic value of the largest distribution throughout the country. The other introduced 1 families, 7 genera, 50 species, mostly trees greening and garden afforestation.

Pinopsida Pinaceae (Pinaceae)

Most trees, rare shrubs, evergreen. A leaf
 larix principis-rupprechtii larix principis-rupprechtii
Shaped or needle bar: Ye Bianping, a rare four prism, on long branches spiral scattered, fascicled on short branches; needle-shaped leaves 2 - 5 pin bundles, was born in the extreme degradation Short branch The top of the base package Leaf sheath . Strobile Parthenocarpic monoecious, microspore Leaves the ball, with numerous whorls of Microstrobilus, each microsporophyll 2 Microsporangium Most microspores have air bags; Megaspore Leaves spiral ball, by a majority of students Cone scales and Bracts Wherein, each bead ventral scales (above) with two anatropous ovule (below), on the back of the bracts and ovuliferous scale separation (only basal binding), after ovuliferous scale development increases Seed scales . cone Erect or drooping. Seeds usually winged; embryo with 2 - 16 cotyledon . Chromosome 13, 22, X=12.
The undergraduate is pinopsida the largest plant and in the economy is an important branch of the 1, there are 10 genera, about 230 species found in the northern hemisphere. Chinese has 10 genera, 113 (including the introduction and cultivation of 24), the distribution of all over the country, most of them are forest species and tree species, and many endemic genera and relict plant.
Bachelor degree with plant needle-shaped leaves Bar or leaves, and leaves Seed scales Spirals, scales and Bracts schizogenous Each with 2 scales, seed and other features.

Pinopsida Taxodiaceae (Taxodiaceae)

Tree。 Leaves spirally arranged, with a tree with leaf type or type two; Strobile Parthenocarpic monoecious, microspore Ye Jizhu scales spirally arranged (only Water jacket Leaves and microstrobilus, Cone scales For students), Microsporangium More than 2 (3 - 4), the non air, ovuliferous scale and Bracts For more than half connate (only top separation), ventral base of the ovuliferous scale has 2 - 9 erect or Anatropous . cone When mature, Seed scales (or bracts) flat or peltate, woody or leathery, can have a 2 - 9 scale breeding seed, seed around or on both sides of a narrow wings. Chromosome: X=11, 33. They are 10 genera, 16 species, mainly distributed in the northern hemisphere. China produced 5 genera, 7 species, 4 genera and 7 species introduced, and distributed in the Yangtze River Basin and south of Qinling Mountains provinces.
Undergraduate plants to seed scale and semi bracts connate, scales with 2 - 9 seeds, leaves lanceolate, subulate, strip or scaly, alternate, spirally arranged or 2 columns (except Metasequoia For students), microspore No airbags and other features.
According to the system principle, Taxodiaceae Jinsong (Sciadopitys) is divided into Jin Songke (Sciadopityaceae), the other part is incorporated Cupressaceae (Cupressaceae). The separate Taxodiaceae is a classification of backward, but the domestic textbooks commonly used.

Pinopsida Cupressaceae (Cupressaceae)

Evergreen trees Or shrub. Leaves decussate or whorled, thin spiral, scale shaped or chaetica, or the same tree with two leaf. Strobile Unisexual, monoecious or dioecious. Leaves decussate microspore, Microsporangium Often more than 2, the bag. Cone scales Cross of 3 - or 4 verticillate, ovuliferous scale base with 1 or more pieces of ventral upright ovule , Bracts Completely connate and ovuliferous scale. cone Usually spherical, Seed scales Peltate, wood or meat, cooked meat or a berry like with open. Two seeds with narrow winged or wingless, or the top 1 long 1 short wings. Chromosome: X=11.
In a total of 22 genera, about 150 species, distributed in the southern and Northern Hemisphere two. 8 genera, 29 species of China, other times the national distribution, introduced 1 genera, 15 species.
In plants with leaves or Verticillate And with two types of scales and leaves, bracts completely connate, Cone scales Decussate or 3 - 4 verticillate, ovule Upright and other features.

Pinopsida Araucariaceae

Evergreen trees The pith, cortex is larger, with resin. Leaves spirally arranged or decussate, squamous, subulate, triangular ovate, lanceolate to oblong, basally extended growth. Dioecious Or the same, Female flowers Single Acremonium, with numerous spiral arrangement Bracts , Cone scales Completely connate and bracts connate, or have a mutual, in bract apex was isolated only ventral tongue shaped cone scales, bead base with a ventral scales Anatropous , ovule Free or buried in the ovuliferous scale and health. 2 ~ 3 years of mature cones, bracts or thick wood Leathery A flat, triangular, apex or caudate cusp; Seed scales Flat and bracts, free or connate, wingless or two winged, or top winged; mature scales and bracts from fruit axis off. Only undergraduate Araucaria Araucaria and Agathis Agathis two genera, about 40 species, distributed in the southern hemisphere, Oceania, South America, north to Malaysia and Philippines, China is part of the introduction. Araucariaceae wood Early wood Tracheid Wall size Bordered pit Each column, for polygonal, good quality; cultivated area for landscape or garden ornamental tree .

Pinopsida On behalf of the plant

Pinopsida cathaya argyrophylla

 cathaya argyrophylla cathaya argyrophylla
Genus of gymnosperms pinaceae. National protected plants . Alias shirt childe, is a high of ten to 20 meters Evergreen trees . It is a special product of China belongs to the third century Relict Rare plants down.
Evergreen trees, with branches in, up to 24 meters, diameter is usually up to 40 cm, 85 cm to dilute; straight trunk, bark dark gray, split into irregular flakes; branchlets and upper branch growth slow, fawn, glabrous, or early pubescent, glabrescent, with slightly uplift Pulvinus No bud; resin, Bud scales Fall off. Leaves spirally arranged, radial scattered, more dense, linear in the upper and lateral branchlets slightly curved or straight, usually 4~6 cm long, 2.5~3 mm wide, apex rounded or obtuse, base tapering into petiole inconspicuous, above midrib sag, dark green, glabrous or pubescent, lower; both sides have obvious surface along midvein white stomatal bands, edge micro - volume, cross section 2 edge resin road; leaf margin with eyelashes. Monoecism , Male flowers Usually solitary in leaf axils for 2 years; Female flowers The solitary in leaf axils. cone Two years to mature, ovoid, 3~5 cm long, 1.5~3 cm in diameter, cooked brown or chestnut brown; scales of 13~16 pieces, wood, clamshell shaped, suborbicular, abaxially with short hairs, ventral base of students and two seeds, persistent; bracts small, ovate triangular, long pointed out, not exposed; seeds obovoid, 5~6 mm long, dark olive green, with irregular spots, a winged 10~15 mm.

Pinopsida Spruce

Evergreen trees . Trunk Straight end . Is China Picea The state of most of the plants, a total of 16 species and 9 varieties, located in the northeast, north, northwest, southwest and Taiwan mountain and subalpine, especially in most species in Hengduan Mountains region, Timber volume Rich. Cretaceous strata of Picea fossil plants of the earliest found in the western United States and Japan. The third century To the late Quaternary The Pleistocene because Picea koraiensis The impact of global temperature, the Spruce from High latitude And to the high altitude area Low latitude Extension and low elevation area, increasing the types of. After the retreat of the glaciers and temperatures rise, the distribution area gradually reduced, since reproduction, the formation of modern Distribution pattern . In China Qinling Mountains To the South and southeast of the plains and southwest low mountain area during the late Pleistocene was found in pollen and spruce cones.
Many features of the spruce trees with drooping branches, whole tree layers. Straight The needle like leaves in a spiral around the stem, the length of 2~3 cm. Director Ye Congchun, if you fall off, Changchun will be retained. woodiness cone Suspension, pebble is formed in a cylindrical shape with curved inward
Bracts, when cone is mature, these bracts will open to let the seed fall off. Tall trees of spruce conifer, about 45m high, diameter LM, crown for narrow conical, bark gray, scaly shedding, big flat, hairy branchlets brown, annual branches. Leaves four prismatic bar, bending, powdery green, apex, four stomatal line, leaf length 1~2cm, leaves on branches spirally arranged. Flowers unisexual, monoecious, blooming in May, October with mature cones, Periodic Strong, generally 4-5 years 1 years, above the seeds of poor quality and low germination rate. The seed weight 3.6-4.6 grams per kilogram of grain seeds 250000-350000, the germination rate of 20-45%. Seed sacks common dry Tibet, 2-3 years after the germination rate decreased 8-15%, low temperature sealing dry storage for 5 years, the germination rate decreased only 5%.

Pinopsida Metasequoia

 Metasequoia Metasequoia
A deciduous tree, up to 35 41.5 meters, diameter of 1.6 to 2.4 meters; bark gray brown or dark gray, split into a flake off; branchlets opposite or subopposite, drooping. Leaves decussate, in green deciduous lateral leaflets pinnately row two column, linear, soft, subsessile, usually 1.3 to 2 cm long, 1.5 to 2 mm wide, midvein concave above, below 4 - 8 stomatal lines along midrib on both sides. Monoecism , Male flowers Solitary Leaf axil Or bract axils, ovoid, decussate raceme or panicle like rows of stamens, decussate, about 20, Anther 3, filaments short, connectives conspicuously; Female flowers Single top branches, from 22 - 28 decussate Bracts and Cone scales Wherein, each of the 5 9 ovule . cone When ripe, the fruit pendulous, blue, edible, subglobose or oblong globose, with four micro edges, 1.8 - 2.5 cm long; Seed scales A thin, transparent wood; bracts, peltate, back cross diamond, a cross slot, when ripe dark brown; seeds obovate, flat, narrow wings around, apex concave.