Effect of humic acid and algereen on growth of lettuce (Lactuca sativa L)‎ by using N. F. T. culture

الملخص EN

The experiment was carried out in March 2012 in theFaculty of Agriculture, University of Duhok inside greenhouse to test the effect of humic acid on growth of lettuce (Lactuca sativa varcapitata).

Seeds were planted in podsfrom March to April.The experiment consisted of three concentration of humic acid , the solution was algereen (sea weeds) about (1ml.l-1) .,Complete Randomized Design (C.R.D.) was used in this studyconsisted one factor that is three concentrations of humic acid (0 and 0.8 and 1.6 gm.l-1) .Theresults appeared that humic acid showed significant increases in all of vegetative growth characteristics (length of stem, length of head, head diameter, number of leaves, chlorophyll content (SPAD.) ,fresh weight of vegetative growth ,dry weight of vegetative growth, fresh weight of roots and dry weight of roots), as compared with untreated plant (control) which gave lower values.

Also significant increaseswere found in the nutrient elementsmacro and micro (N.P.K %) and Fe and Mg ppm when the plants were sprayed with 1.6 gm.l-1 humic acid as compared with control.