Low Cost Gelling Agents for In Vitro Seed Germination of Radish (Raphanus sativus L.) Var. Beeralu Rabu

Abstract

In vitro cultivation of plant tissues is generally carried out in a solid or semi-solid nutrient medium, using gelling agents. Agar is a polysaccharide extracted from sea weeds is used commonly in plant tissue culture to solidify the medium. Unreasonable price of agar and fear of over-exploitation of its resources necessitated the search for low costs materials as alternative to agar. Radish {Raphanus sativus L., Brassicaceae) is an important vegetable plant with varied medicinal properties. Therefore, the present study was designed to examine the potential of alternative cheap gelling agents {corn flour, kithul flour, barley, saw, wheat flour and undu flour) for seed germination of radish {Raphanus sativus L.) var. Beeralu Rabu. Seed germination was observed on MS basal medium supplemented with different alternative gelling agents (10%) and agar (0.8%). Plantlets weights, heights and number of germinated seeds were recorded after 4 weeks of culture. Results showed that agar and alternative gelling agents successfully produced plantlets from the seed explants of radish after 4 weeks. The highest mean height (16.89cm) of plantlets was obtained in MS basal medium with agar and highest mean weight (1.65g) of plantlets were obtained from MS medium supplemented with corn flour. Furthermore highest number of seeds (3.4) out of 5 seeds was germinated in the medium with corn flour. Mean height, weight and number of seeds germinated in MS media with corn flour were not significantly different from agar. Cost of gelling agent was reduced in 95% by using corn flour as solidification agent instead of agar. Corn flour (10% w/v) has shown a greater potential as a cheaper alternative gelling agent for agar based medium as per the cost analysis.