TITLE:
Interaction Effect of Plant Growth Regulators on Shoot Micropropagation of Aromatic Plant Origanum elongatum (Bonnet) Emberger & Maire
AUTHORS:
Rajae Benkaddour, Naouar Ben Ali, Latifa Azaroual, Patrick Martin, Ahmed Lamarti
KEYWORDS:
Auxins, Cytokinins, Gibberellic Acid, Macronutrients, Micropropagation, Polyamines, Origanum elongatum
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.13 No.8,
August
25,
2022
ABSTRACT: Origanum elongatum (Bonnet) Emb. & Maire, is a medicinal, aromatic
and endemic plant of Morocco, characterized by its pharmacological effects, and
is commonly used for the production of essential oils and aromas, resulting in
high harvest and overexploitation pressure. This is why the present study aims
to implement the in vitro micropropagation of Origanum elongatum for optimal vitroplant
production. Six macroelements were tested (SH, SD, N30K, MS, MSm and B5) and
the SD medium was selected for vegetative propagation of the explants. Seven cytokinins: adenine (Ad), N6-(2-Isopentenyl) adenine,
zeatin (Zeat), kinetin (Kin), benzyladenine
(BAP), 1,3-diphenylurea (DPU) and thidiazuron (TDZ) were then evaluated at five
concentrations (0.44, 1.33, 2.22, 3.11 and 4.44 μM/L) on growth, development,
budding, rooting and hyperhydricity. 0.44 μM Kin was selected and combined with
three auxins: indole-3-acetic acid (IAA), indole-3-butyric acid (AIB), and
1-naphthaleneacetic acid (NAA) at four concentrations (1.14, 2.85, 4.56
and 6.27 μM/L) to improve rooting and association with 1.14 μM IAA was shown to
be efficient for roots development. Different concentrations of gibberellic
acid (0.29, 1.5, 2.60 and 2.89 μM/L), combined with 0.44 μM/L Kin and 1.14 μM/L
IAA, were tested and 2.60 μM/L GA3 gave maximum buds and shoots.
Then, the combination of three polyamines at five concentrations (1.134, 3.402,
5.67, 7.938 and 11.34 μM/L) with 0.44 μM Kin and 1.14 μM/L IAA showed an
increase in the number of buds and shoots for 7.938 μM/L putrescine and 3.402 μM/L spermine. Finally, seedlings with good
foliar and root development were acclimatized.