The present study was conducted in the experimental farm of Agricultural
Development System Project in Giza, during the growing seasons 200212003 and
200312004, using humic substances extraction from farmyard manure (HAs) to study
their effect on soil nutrient and growth of Ficus benjamina L. and Geranium
sanguineum L. plants. The humic acid was extracted with KOH and HN03 and
characterized by chemical methods and UV, visible absorption and infrared
spectroscopic analysis. The humification index, humification ratio, and humic acid%
values were 0.70, 0.42 and 39.3, respectively. The elemental composition of humic
acid was as following: C 44 %, N 4.73 %, H 4.21 %, S 1.52%, 045.54% and C:N
9.30. The absorbance decreased as wavelength increases and no absorption found in
range of 300-700 nm while a small absorption peak appeared at wavelength near 270
nm. The EJEe ratio of cleared humic acid was 5.11. Sandy and loamy sand soils were
treated with HAs (6 g L·¹ at pH5) at field capacity, nitrogen, phosphorus, zinc, copper,
manganese and iron concentrations increased as compared with untreated soil. The
effect was more pronounced in sandy than the loamy sand soil. The foliar application
treatments of extracted HAs at pH 5 (2, 4 and 6 ml of HAs 1 00mr1.) with 0.1 N KOH
and 0.1 N HN03 from farmyard manure has significant improved the root mass, root
length, roots number, leaf area, plant height, number of branches plant" of Ficus
benjamina L. and Geranium sanguineum L. and nutrient content of Ficus benjamina.