RESPONSE OF SEED YIELD, MINERAL COMPOSITION,

ESSENTIAL OIL CONSTITUENTS OF PARSLEY AND

CORIANDER TO COBALT FERTILIZATION

[66]

Khattab¹, M.E. and Laila M. Helmy²

ABSTRACT

Two experiments were conducted during 1999 / 2000 and 2000 / 2001 to investigate the effect of different concentrations of cobalt fertilization on growth, number of inflorescences per plant, inflorescence diameter (cm), seed yield (gm / plant) and seed chemical composition of parsley (Petroselinum sativum Hoffm.) and coriander (Coriandrum sativum L.) plants. The plants were grown in clay soil. One month after seed sowing, cobalt was applied using CoSO₄ solution with four treatments
(0, 25, 50 and 100 mg Co/kg soil). The measured parameters of plant growth, seed yield and seed N, P and K contents were significantly increased with low levels of cobalt fertilization, particularly 25 mg Co/kg soil relative to that of control except number of inflorescences per plant and K content in dry seeds of coriander. Increasing cobalt fertilization up to 100 mg/kg soil, decreased all measured parameters below those of untreated plants except inflorescence diameter of parsley. In terms of parsley seed oil yield (ml/plant), significant increase was obtained from 50 mg Co/kg soil, while in coriander, the maximum value was obtained from 25 mg Co/kg soil. Increasing cobalt levels, significantly increased the seed contents of Mn, Zn, Cu and Co, while an opposite trend to Fe-content was observed in both crops. A little higher effect on seed protein percentage was noticed with 25 mg Co/kg soil in both crops. Volatile oil constituents of the seeds were studied with GLC analysis. Twenty four compounds were identified in both crops. These number of identified constituents included 10 compounds in parsley and 14 in coriander. It was found that apiole and linalool were the major constituents forming about 56.0 and 76.0% of parsley and coriander seed essential oil, respectively.