Enhanced Protocol Development for in vitro Multiplication and Rooting of Vanilla (Vanilla planifolia Andr.) Clone (Van.2/05)

Abstract

Vanilla (Vanilla planifolia Andr.) is a multipurpose spice in the world. The crop had been introduced to Ethiopia from Mauritius and it is still under maintenance at the Tepi National Spices Research Center (TNSRC). It is commonly propagated through stem cuttings which could arrests subsequent plant growth and development and serves as an ideal means for the spread of varied diseases. To solve the mentioned problems, no efficient in vitro protocol had so far been developed to propagate this vanilla clone in Ethiopia. Therefore, this study was initiated to address this gap by developing efficient protocol for the enhanced multiplication of this accession (Van.2/05). In this study plant material was taken from TNSRC. The experiments were carried out in Jimma Agricultural Research Center (JARC) at Biotechnology Laboratory. Nodal explants and Murashige and Skoog (MS) (1962), basal medium were used exclusively throughout the experiments. The experiments were laid out in Completely Randomized Design (CRD) with factorial treatment combinations and replicated three times for plant growth regulator (PGR) assisted experiments. In the study, shoot multiplication, the combined use of 2 mg l-1 6-Benzylamino Purine (BAP) and 0.5 mg l-1 Naphthalene Acetic Acid (NAA) was proved to be the best providing the highest shoot mean number (5.33) and length (4.9 cm) of shoots after five weeks of culture. The combined use of different MS basal medium strengths and Indol -3-Acetic Acid (IAA) concentrations were employed. Therefore, ½ MS strength combined with 0.5 mg l-1IAA produced mean number of 4.00 roots per plantlet with mean length of 6.1cm. The average rate of ex-vitro survival was 83.4%. Therefore, the advent of this protocol could have considerable value to enhance the expansion of vanilla cultivation in Ethiopia.