EFFECT
OF COBALT FERTILIZATION ON THE YIELD,
QUALITY
AND THE ESSENTIAL OIL COMPOSITION
OF
PARSLEY LEAVES
[56]
Laila, M. Helmy1 and Nadia Gad2
ABSTRACT
Parsley (Petroselinum sativum Hoffm.) plants were grown in plastic pots filled with Nile-delta clay soil during 1998/1999 and 1999/2000 seasons. One-month-old plants were soil supplemented with 0, 25, 50 and 100 mg Co per kg soil using CoSO4 solution of different concentrations. Plants were harvested 2 months after seed sowing and reharvested again for 3 additional harvests at monthly intervals. Plant growth expressed as plant height, leaf fresh and dry weights, number of leaves per plant as well as root fresh and dry weights were significantly increased with low levels of Co addition particularly 25 mg Co per kg soil. Increasing Co level dramatically reduced leaf chlorophyll and Fe contents. 25 and 50 mg Co/kg soil increased N, P, K, Ca, Mg, Mn, Cu, Zn and Co levels in parsley leaves relative to that of control. LAA content were significantly reduced with increasing levels of Co fertilization, while TSS and TA levels showed no response with Co addition. Low levels of Co fertilization significantly increased essential oil yield of parsley leaves. The main aroma constituent of parsley leaves, 1, 3, 8-p-menthatriene which forms about (76%) of leaves essential oil, showed about (10%) increase over that of control with 50 mg or higher levels of Ni fertilization per kg soil.