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In Botany is called cataphyll or catáfila to each of the leaves usually modified and reduced to protect the buds of the plant that are at rest, particularly in underground organs as spare bulbs and rhizomes . They often flakes and do not have chlorophyll and do not have the function to perform photosynthesis . In certain cases, besides the protective function, also have the role of reservoir of nutrients, such as in the case of the bulbs of onion ( Allium cepa ) or garlic ( Allium sativum ).

The caudex (plural: caudices), also known as lignotuber is a term botanical describing a shaped morphology of stem which appears as a persistent spheroid elongation often woody and non- photosynthetic crown root or stem axis of a herbaceous .
The caudices may extend below ground. This structure appears commonly (but not limited to) means plants adapted to xeric , and functions as a water-storage.
Plants caudiciformes has caudex. Some notable genera and Pachyrhizus (family Fabaceae ). Some eucalyptus trees and other plants adapted to periodic fires have also caudex.

In horticulture , gardening and viticulture is called nipple to stem that sprouts from the main branches, the trunk or the roots of trees.
The energy consumption of pacifiers is very high and is popular name comes from that feature.
The nipple can be damaging both the production and health of trees. In agriculture are held pruning selective ring pacifiers.
Olive unproductive stems are called "Ramon" and through these regulates selective pruning the vegetative growth of olive trees.

The ciato (from Greek : ??a??? 1 , 'drink') is a type of special inflorescence consisting of a pseudanto , ie a structure having the appearance of a single flower , but actually consists of several flowers. This type of inflorescence is only in the genus Euphorbia and Chamaesyce , which is one of the most diverse within the kingdom Plantae .

The similar characteristics to those of a solitary flower ciato are highlighted by the brightly colored nectaries often petaloid appendages crowned together with the aforementioned nectaries, or colored bracts are located under the ciato. These bracts are called ciatofilas Goniostema section of the genus Euphorbia .
The ciatos are rarely solitary, but are mostly found as peaks bíparas or compound inflorescences as pseudoumbela (top of umbel arrangement, but with centrifugal flowering [the center to the periphery]).
In a group of species Malagasy Goniostema section of the genus Euphorbia ( E. aueoviridiflora , E. capmanambatoensis , E. iharanae , E. leuconeura , E. neohumbertii , E. viguieri ) there is a tendency to form an additional pseudanto grows from the top. Possibly as an adaptation to pollination ornithophilous , the ciatos have specialized so that the ciatofilas are vertically around the axis in a protective manner, but back to the nectaries inaccessible. By way of compensation between these ciatos are other naked and barren whose sole function is to produce nectar [ citation needed ] .

In Botany , the vascular cylinder is the innermost portion of the root , which includes everything that is inside the endodermis , ie, the vascular system ( xylem and phloem ) and the parenchyma associated. Is bounded by a tissue called pericycle , a multilevel unit (in gymnosperms and some angiosperms , including some grasses ), which may be lacking in aquatic plants and parasitic plants . Their cells are parenchyma, thin walled, elongated, rectangular in longitudinal section. May contain laticifers and secretory ducts. Sometimes it is interrupted by the differentiation of xylem and phloem elements. In the spermatophytes the pericycle has meristematic activity as causes of the cambium , the phellogen and lateral roots. Esclerifica often in old roots of monocotyledons without secondary growth.

With regard to the vascular system, the phloem strands form below pericycle differentiation and is centripetal, the protophloem is on the periphery. In angiosperms comprises sieve tubes and companion cells, whereas in gymnosperms sieve consists of cells, there is seldom fibers. The xylem is arranged in cords alternating with phloem. The protoxylem is exarco, or that development is centripetal. The metaxylem vessels and tracheids may have, sometimes not at the center of the cylinder, when it does, the elements of larger diameter at the center. In that case, the cylinder is described as vascular aktinostele as for example in Clintonia or protostele. Depending on the number of "poles" (cords) of protoxylem recognize different types of root. With a pole is called Monarch ( Trapa natans , an aquatic plant), with two diarca (in the pteridophytes and dicots such as Daucus , Solanum , Linum ), with three, patriarch ( Pisum ), with four Tetrarch ( Vicia , Ranunculus ), with five pentarca and poliarca with several poles. The roots of gymnosperms are diarchic or poliarcas. 2 xylem cords are interconnected by side anastomosis in most plants. The parenchyma is associated with the conducting cells. May have resin ducts in primary phloem, protoxylem poles and in the center of the root may have a central channel. In old roots without secondary growth can lignify.




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