complex hierarchy taxonomy of species includes many categories.Plant families are below the order (order) and higher kind.Their names are formed in accordance with the rules, which are governed by International Code of Botanical Nomenclature.The name of the family of plants is formed by adding to the base name of the type genus of the standard end -aceae.Thus, for example, formed the name of the Rosaceae family (Rosaceae), which consists of the genus name «Rosa», on the basis of which take Ros- and add the ending -aceae.The scientific classification of derivatives are sometimes used grades: superfamily and subfamily.
plant families in the modern sense emerged in the early XX century.For the first time this category has introduced a botanist Pierre Magnol from France back in 1689 For decades, it represents a group of completely different character.This practice of using this name ended only in 1906 with the adoption of international rules of botanical nomenclature.According to the rules, this name came to mean everything that previously called orders in Latin or families - in French.
Despite the diversity of plants, it should be noted that some are more similar to each other, and some - less.This similarity is determined by the relationship of these plants.It is related species underlie the formation of families.It is assumed that on this planet there are over 350,000 species of plants:
- spread Moss family: has 1.3 thousand. Genera and 25 thousand. Species;
- ferns of 300 genera and 11 thous. Species;
- Horsetail: 1 genus and about 25 species;
- lycopsids: 4 genus and 1 thousand. Species;
- gymnosperms: 60 genera and 700 species;
- angiosperms (flowering): more than 500 families, about 13 thousand. Genera and more than 250 thousand. Species.
there is a family of plants that are most interesting to people in terms of their use in everyday life.Without these plants would have been impossible human life at all, because many of them make up a significant part of his diet.One of the most common is the family of dicotyledonous plants.The characteristic features of such plants are: the presence of two cotyledons;the number of different elements of the flower in the overwhelming number of them is equal to or a multiple of 4 and 5;located annularly conductive fabric.The root system of these plants are mostly rod.This family is represented by all life forms.Among dicots have grass, shrubs and trees.This family is about 4/5 of flowering plants on the planet.
legumes belong to the class of bipartite.This is a very abundant species.Flowers have its representatives consist of five unequal petals, are irregular in shape, 10 stamens.Legumes characteristically arranged.Their device is called a botanical term "bean".A common feature of the family is a one-term ovary that is not divided into shares, and the fruit of all plants polyspermic, butterfly.Ripe fruit bursting at the seams leaflets, which are attached to the seed.
Bean has about 6.6 thousand. 200 species and genera.They are spread all over the planet.This family is divided into subfamilies: caesalpinioideae, mimosa, legumes.The share of the latter account for the largest number of plants in the family.Some of them are the most important human food: beans, lentils, peas, chickpeas, peanuts, soybeans.The fruits of these crops are high in vegetable protein, many minerals and vitamins.Many of them are used as a valuable animal feed: clover, vetch, sainfoin, clover, alfalfa.Herbaceous legumes representatives capable of extracting nitrogen from the atmosphere, are the main plants used in land reclamation.
