Assessing the Effects of Soil Humic and Fulvic Acids on Germination and Early Growth of Native and Introduced Grass Varieties

摘要

The presence of humic acid (HA) generally affects positively and at various extent the germination and early growth of all varieties examined but in some cases negative effects are measured on the early growth. However, the response of the species varieties, examined either singularly or in combination by two, does not show any specific trend as a function of either the type or concentration of HA. This result can be ascribed to the fact that the three HAs used for the germination and early growth experiments do not show any significant differences in their compositional, functional and structural parameters determined by chemical methods and spectroscopic techniques. Thus, it is impossible to find out any direct relationship between HA chemical and physicochemical parameters, or concentration, and germination and growth response of the four varieties examined either singularly or in combination by two.