Pear
Group types of trees and bushes, that behaves to family of varicoloured, sort of Pyrus. List'ya, as a rule, that fall off; pestles in gynecium from 2 to 5. 0З ovaries them accrete between itself and with a floral bed which takes shape mugs; petals in a bud are located tiled; the nests of fruit cover a shell (nutreplodkik). Besides such belong family economic important plants as apple-tree, wild ash, quince, medlar and other The cultural form of pear is known under the name of Pyrus domestica of At favourable terms a pear arrives at large sizes - more 12,5 meters in a height and 5 meters in the diameter of crown. The phyllotaxy of is spiral in 5 rows. Sheet of widely egg-shaped form, 2,5-10 see long of shortlysharp; color - rifle-green, brilliant, lower side of of sheet bluish green, in autumn goldish-orange. Form of crown of of open-growing tree - pyramidal or rounded, inclined to to densifying. An annual increment is made by 30-40 see. Buds in a pear, as well as at other trees of family of two types: vegetative and genesic. Vegetatavnie of bud more shallow and sharper genesic - anymore and more dull. External differences between two types of of buds increase from time of formation of these buds to the exit from them of escapes. Time and flowering form April is May, flowers whites, 3 see in diameter, 5-petalous, for 3-9 in the umbrella-shaped brushes. A fruit is an apple of as a rule - prolate form with expansion in an underbody, there are breeds of with spherical garden-stuffs. В wild kind in Europe a pear is widespread approximately to 60° с. ш. On the north border of natural habitat - liquid. К 2006, as a result of successful selection of frost-hardy sorts of a pear is effectively grown on garden-plots, located on Ural and in Western Siberia to 55° с. ш. Suppose, that the origin of cultural sorts of pears is related to hybridization of row of kinds, in particular Р. achras of G of rtn., Р. persica of Pers., P. cordata of Desv., P. elaeagrifolia of Pall. pears were cultivated in ancient to Persia, Greece and Roman empire. В present tense counted тычячи sorts of pears. Разные the sorts of pears are used as decorative or actually fruit trees. В 2005 the world production of pears was made by 15 million tons (estimation of Minsel'khoza of the USA). The most producer of pears is China. |