EFFECT OF SOME GROWTH REGULATORS AND ELEMENTS ON GROWTH AND REPRODUCTIVELY OF BLACK CUMIN ( Nigella sativa L.) PLANTS.
1- Vegetative growth, endogens phytohormones and histological studies
El- Desouky, S. A.*; Kheder, Z. M.*; Faten , H. M. Ismaeil*; Moftah, A. E.** and Hayam, A. Abd El- Gawad*
* Agric. Botany Dep.,`Fac. of Agric., Benha University
** Botany Dep.,` Fac. of Agric., Shebin El-Kom, Minufiya University
In the present study the growth of black cumin Nigella sativa L plant were studied using certain elements (i.e., boron, sulphur and potassium) and some the growth regulators (i.e., Naphthalene acetic acid, Benzyl adenine and Paclobutrazol) as separated treatments as well as some of their combination.
The most of applied treatments hastened seedlings emergence of Nigella sativa expect paclobutrazol at 1 ppm. Meanwhile, the combination of PP333 with (B +S each at 50 ppm) minimized that retardation to reach nearly one third of paclobutrazol when applied separately.
All the applied treatments showed an inhibition of vegetative growth at 66 days of plant age (i.e., first sample) that reached to the level of significance in most cases two seasons.
All the second sample (176 days after sowing), treatments of BA at the two concentrations, NAA at 50 ppm; (B+S at 50 ppm for each); BA at 5 ppm + (B+S each at 50 ppm) and NAA at 10 ppm + (B+S each at 50 ppm) increased the vegetative growth of treated plants during the two seasons.
The treatments of BA at 25 ppm, pp333 at 1ppm and NAA at 50 ppm increased the endogenous content of auxin in roots with more than two, three and nine times comparing with control roots. But, this content was decreased with BA at 5 ppm + (B +S each at 50 ppm).
Endogenous auxin was increased with pp333 at 1 ppm and NAA at 50 ppm, yet it was decreased with BA either separately or in combination concerning.
The endogenous gibberellic acid (GA3), the only BA at 25 ppm gave a detectable amounts in roots, yet, the rest of treatments either in roots or in shoots did not give any detectable amount of this hormone.
Meanwhile, in ease of endogenous cytokinins it was decreased with different assigned treatments in shoots, yet, it was decreased in roots with exogenous applications of BA.
In histological studies, Increase of root diameter was mainly due to that increase in each of cortex and vascular tissues. Also, different treatments increased stem diameter to reach its maximum with BA at 5ppm + NAA at 10 ppm + (B + S each at 50 ppm) followed by PP333 at 1ppm. |
