Germplasm Conservation of Economically Important Medicinal Plant Nyctanthes Arbor-Tristis L. Through Encapsulation Technique and Maintenance Under Slow Growth Condition

Abstract An efficient encapsulation and germplasm conservation protocol were developed for Nyctanthes arbor-tristis L. In this study the gel matrix containing three percent sodium alginate (SA) and 100 mM calcium chloride (CaCl2. 2H2O) was found best for the formation of encapsulated seeds from node explant of this economically valuable species. The viability of encapsulated seeds and shoot sprouting potential was optimized. Encapsulated seeds stored at 4ºC and 24 ºC maintained its viability up to 90 days and showed sprouting potential 42.89±6.04 and 33.53±7.15 percent respectively. Node explant maintain under slow growth condition up to 180 days on one-eighth (1/8th) strength MS medium supplemented with 0.5 percent sucrose found suitable to maintain high span viability percent (40.28±2.04) with average number of shoots/ node (1.61±0.28) and shoots length (1.12±0.32 cm) respectively. One-eighth (1/8th) strength MS medium supplemented with 0.5 percent sucrose and enriched with 0.5 mg/l abscisic acid (ABA) prolonged the viability up to 40.36±1.01 percent of explant. The best rooting response was achieved on half (½) strength MS medium enriched with 4 mg/l indole-3-acetic acid (IAA). The rooted plant shows 65 percent survivability in open field condition. The true-to-type clonal fidelity assessment of tissue culture recovered acclimated plants with start codon targeted (SCoT) primer profile shows same banding mobility patterns as with source parent mother plant. The maximum banding profile is monomorphic and consistent. Hence on this basis it confirmed the true-to-type clonal stability among them. The protocols display the novel method for conservation of this species under in-vitro condition and facilitate easy exchange of plant germplasm.