MSc

The study titled “In vitro propagation of sandal (Santalum album L.)” was carried out in tissue culture lab of College of Forestry during 2011-2013. The objective of the programme was to standardize a protocol for in vitro propagation of sandal through axillary bud culture and somatic embryogenesis.
Variation in fungal contamination associated with the time of collection of explants was found. Explants collected during November-April showed less contamination (<11%) compared to rainy season (>90 %). Treating with combination of Mancozeb 75 % WP (Indofil M-45) and Carbendazim 50 % WP (Bavistin) fungicides was effective to control fungal contamination. However, different combinations were effective depending on the time of collection of explants. In order to control bacterial contamination surface sterilization with 0.15 per cent HgCl2 for 10 minutes was effective.
WPM medium was found to be superior over MS and ½ MS with respect to the average shoot length and average number of leaves. Moreover, cultures in WPM were found to be healthy with less leaf fall. Addition of BA or kinetin singly or in combination was effective for the production of multiple shoots than control. Higher concentrations of BA (3 mg l-1) reduced the number of multiple shoots, while in kinetin at higher concentrations increased the number of shoots per explants. There was also a considerable decrease in shoot length with the increase in concentration of BA above 0.5 mg l-1. Except for the multiple shoot production, all other growth parameters observed in cytokinins were inferior to control. Moreover, shoots of cultures in BA were stunted and were associated with heavy leaf fall and rudimentary leaves. But in kinetin, cultures are devoid of these defects. Thus the combination, 0.5 mg l-1 BA + 1 mg l-1 kinetin was found to be effective for multiple shoot induction by considering all the growth factors. Auxins in combination with cytokinins resulted in delayed bud break, leaf initiation and reduction of multiple shoot induction compared to cytokinins alone.
101
However, auxins promoted shoot elongation and leaf production in combination with cytokinins compared to cytokinins alone.
Subculture using single shoots excised from the mother explants failed to develop; while, transferring of new shoots formed along with primary explants was effective. Subculture to media containing kinetin increased the shoot length, leaf area and reduced leaf fall. When media containing combination of auxins and cytokinins was used for subculture, increase in shoot length and number of leaf production was observed. However, cultures in BA containing media were noted with high leaf fall, reduced inter nodal length and rudimentary leaves towards the tip of shoot. While in media with kinetin, shoot length was increased and no leaf fall was observed. Auxins in the media did not promote new shoot formation. Root induction through incorporation of different auxins in the media and pulse treatments failed to induce rooting in the cultures.
Somatic embryos failed to develop from, ex vitro explants. But from these ex vitro inter nodal explants in 0.5 and 1 mg l-1 kinetin, shoot development was observed. Direct embryogenesis could be induced from in vitro explants cultured in media containing BA 0.5 and 1 mg l-1. On inter nodal explants, globular shaped somatic embryos were formed on its surface and these were then developed to the torpedo stage. Further development of somatic embryos was arrested.