Abstract
Over-exploitation of trees by increasing human population has put an enormous pressure especially on those species having slow growth and low reproduction rate. Desert teak (Tecomella undulata (Sm.) Seem) a multipurpose agroforestry tree of arid zone has fallen on the verge of extinction in Iran due to lack of efficient seed reproduction. Inherent low adventitious rooting has caused vegetative mass macro- and micropropagation (organogenesis pathway) of this tree to be unsuccessful. Somatic embryogenesis (SE) pathway by production of bipolar embryo capable of development into a complete plantlet can solve the problem. Hence, a research was carried out to evaluate the feasibility of in vitro regeneration of the tree by SE. Ovary extracted from un-pollinated flower was cultured in the media supplemented with different auxins and cytokinins (CKs). The results showed α-naphthalene acetic acid (NAA) was superior in induction of embryogenic callus (EC). NAA ranging 5.4–21.5 µM could induce the highest ECs which exhibited developing pro-embryogenic masses (PEMs) and globular somatic embryos. Both CKs, thidiazuron (TDZ) and N6-benzyladenine (BA), though induced good callogenesis at low concentrations but the formed calli were non-embryogenic. Proliferation of NAA–induced ECs revealed that hormone-free medium is the best choice. However, the media containing 40.5 and 54 µM NAA alone could also induce somatic embryos along with callus proliferation. Effort for maturation of the obtained globular, hear-shaped and torpedo embryos did not yield satisfactory results. Low BA-contained medium led to secondary SE. More research is expected to be undertaken to optimize SE in desert teak.
“Biochemical characterization, cytotoxic, antimutagenic, anticancer and molecular docking studies on Tecomella undulata”
