Abstract

In the present study, sodium alginate, degraded by Co-60 gamma rays, was used to evaluate the efficacy of irradiated sodium alginate (ISA) on Foeniculum vulgare Mill. The aim of this study was to find out the effects of various concentrations of ISA viz. deionised water (control) and UN (un-irradiated), 20, 40, 60, 80, 100 and 120 ppm ISA in order to get the best response of fennel in terms of various attributes. The growth attributes (shoot and root lengths, number of leaves, fresh and dry weights per plant), yield and quality attributes (number of umbels per plant, number of umbellets per umbels, 100-seed weight, seed yield per plant, content and yield of essential oil) and biochemical parameters (total chlorophyll and carotenoids contents, carbonic anhydrase activity, nitrate reductase activity and proline content) were determined at 70 days after sowing. The results obtained by treatment with un-irradiated sodium alginate showed poorest effect and gave equal value to the control for all the studied attributes and did not significant to each other in its effect. Of the eight ISA concentrations, 80 ppm proved to be the best concentration compared to the other foliar concentrations of ISA. The present work revealed that ISA, applied as leaf-sprays at concentrations of 20 to 120 ppm, improved growth, yield and quality attributes and biochemical parameters of fennel significantly. However, further investigations are required to comprehend the mechanism and mode of action of alginate-derived oligomers for plant productivity and quality.

Key words: Foeniculum vulgare Mill, irradiated sodium alginate (ISA).