الفهرس 
Effect of soaking in water
Root length (cm)Only 14 pages are availabe for public view
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Abstract
Many ornamental trees and shrubs are propagated mainly by seeds. Irrespective of easiness of such propagation, it is usually faced by some barriers which make it difficult to be carried out” as the seeds is considered in a dormancy state”.For example , some seeds require a long period for their slow germination , others loose viability quickly while most of them have hard or impermeable seed coat ;which prevents penetration of water and oxygen into the seeds. This later may be modified by acid treatment, such as a soak in two times their volume of concentrated sulphuric acid . A water soak may be helpful in softening the seed coat or removing inhibitors ; it also stimulates germination in some cases .
In addition , seeds of some of plants don’t germinate in spite of presence of the favorable environmental conditions for this which means that their seed tissues are in a rest.
In some cases two treatments may be necessary to overcome double dormancy of many woody shrubs and trees seeds, such as a hard coat and chemically inhibited or dormant embryo . The former can be broken by mechanical or acid scarification followed by water soaking, and the later by stratification.