Mario Cecarini
www.cactusedintorni.com

They are called FAT, or more properly succulent plants that are developed tissues containing liquids, which store: in the leaves, the stem, roots, in order to survive long periods of drought. For which "succulent" (not in the sense of tasty), the name is more correct since the bulge is composed of juice without any presence of acids. However some time in some countries, including Italy, the term is common to succulents that will not be easy to change.
Often used to make the distinction between cacti and succulents not cacti, to indicate the one hand those plants belonging to the cactus family, Cactaceae and other all other families.

They have succulent leaves, with some exceptions, not the succulent Cactaceae as Lithops, Conophytum, Aloe, Agave, Echeveria, Crassula, Kalanchoe, etc.. They, though in many forms, are typical of areas with not too prolonged drought, can survive in dry periods up to wither or even dropping their leaves as a final defense.
Species with succulent stem are those which belong to the majority of cacti having mostly leaves transformed into plugs in order to reduce perspiration. The stems are globular, columnar and green because of chlorophyll.
The succulence radical is characteristic of some cacti to tap-root, but especially of Bowiea, Ceropegia, Pachypodium, Adenium, Fockea, Ibervillea, Cucurbitaceae, etc.., And in general of that vast group defined caudiciforme having a bulge baseline (caudex) where often the succulence of the rhizome that connects the base of the stem. The caudex is almost never green, for which no photosynthesis takes place, can be located both below and above the ground. Some species, typical of desert regions, have developed tuberous roots, fibrous, can grow very wide just below the surface, to enjoy the night dew. Often the aerial part dies while the roots are able to survive and rebuild the plant when conditions are more favorable.

The CACTUS belong to a family of xerophytic plants, comprising about 100 genera and two thousand species, mostly succulent stem (cauline), globular in shape, columnar, cespitose, paddle, hanging, prostrate, leaf-, articulated in coast, to tubercles, surface spinosa or glabra, stellate cross-section, circular, oval. Regarding the dimensions ranging from those having a height and a diameter of some centimeters up to those with a diameter of one meter and a height of a few tens of meters.

Often also called cactus cactus plants that are not, as happens with some branching and columnar Euphorbia. In these cases it would be enough puncturing the plant with a pin to see out of a white latex detector of a plant belonging, for the most part, to the family Euphorbiaceae and not of Cactaceae.
These plants, typical for the most part of the arid regions and low atmospheric humidity, live in an environment that is not equal for all. In fact we can find them in areas subdesertiche pseudodesertiche and, in temperate regions but also in the snow, as at sea level to over 3000 meters of altitude, and even in humid tropical areas. All this has led them to implement a series of morphological adaptations with reference to the form, and with regard to the physiological functioning of tissues. We observe that plants that have reduced the size of the leaves (which often falls during sleep), or been transformed into thorns; have assumed an oval or cylindrical, often with ribs to reduce the incidence of solar rays, whereby the outer surface covered of an impermeable layer, or have the body covered with whitish bristles; develop extensive roots, or produces a long taproot central reduce the number of stomata, implement breathing at night and make minimal metabolism during rest. The purpose of all this is to reduce perspiration, which involves loss of fluids, and try to take water from the air that is above the ground.

To defend against the animals are camouflaged in the succulent, growing in inaccessible places or developing tissues poisonous. The flowers are of great importance for the conservation of species: some are open at night to call the night birds, pollinators, other insects attracted by the smell, color, nectar. Other species open at different times to avoid hybridization.
Seeds also play an important role: some are provided with wings or are very minute in order to be easily dispersed by the wind, other implement a dormancy so as not to germinate until it occur favorable climatic conditions, like some of the fruit not allow the escape of the seed if they are not wet, or throw away the seeds by means of an elastic mechanism. Some plants are in such a way that the articles or parts of the stem from sticking to the fleece of some animals, that in this way will provide for the transport and spread to other areas.

The element that links the family of Cactaceae consists dall'areola, a kind of bearing feltroso from which emerge pins, quills, bristles, hairs, capable of replacing the nodes that have the other plants. The cacti have ribs in areolae along the edges of the same coasts, those provided by the show leaves the armpit of them, than with the areolas have tubercles on top of them. Originate from small regions of branches and flowers, which can be located towards the apex, which is far from it. Some genres, reaching maturity, they emit a cefalio (cluster of bristles and fluff) who is and who the apex along the stem. This may, for some genres, the end of the growth of the plant or branch bearing the cefalio.
The plugs, arising from modified leaves, are intended to reduce perspiration (equal to the waxy layer that covers the epidermis of the stem), and reflect the light sull'areola convey the condensation water. They take on a huge variety of shapes, thickness, length, texture, texture, color, number, section, provision. The plugs also feature a surface structure anchored to the areola and not intimately connected to the underlying tissue, so if removed the plant does not suffer any damage.

The leaves are persistent only in the Cactaceae subfamily Pereskioideae, a form of transition is not yet a real juicy. In Opuntioideae the leaves can be very small and very early fall, or in the large and persistent. Typical are also glochids of Opuntia: tiny thorns that can detach easily from the plant to join, so it's very boring, the party has had the misfortune to touch them. The roots can be long and shallow, which is shorter but taproot.

The flowers, mostly in radial symmetry (division into equal parts on different floors) and in some cases to bilateral symmetry, can be solitary or crown, large (also 10 cm) or small (only a few mm.), But without a clear differentiation between the cup and the corolla. Last for the most part only a few hours even though there are exceptions. Some species open their flowers at night and close them at dawn, or vice versa, others were temporarily closed during the hottest hours or lack of sunshine, others still have a rash that lasts several days, or are able to flourish in later times . Flowering occurs for many species of cacti in the spring, but notable are the cases of summer-flowering, autumn and even winter. The flowers originate from a vegetative bud changed and although hermaphrodites (presence of stamens and pistil), are rarely self-fertile (self-incompatibility). There are also cases of dioecious plants, ie the presence of the two sexes in different plants (male plants and female plants).

The fruit, resulting from the transformation of the receptacle and pericarpello, is almost always made from a berry, fleshy or dry, often indehiscent (not opening at maturity), laying seeds in moderate quantities and various sizes.
The Cactaceae are typical of the American continent, extending from Canada to Patagonia, but are especially common in the steppe grasslands and semi-deserted although extending to the Andes mountains well above 4000 meters, and a limited number of species in nature epiphyte, even in hot and humid environments typical of tropical and subtropical forest.

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3. Carnivorous plants (part three)
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Tags: botany , cultivation techniques , crop varieties

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