an investigation of the effect of autotetraploidy on essential oil content and some of quntitative and qualitative characteristics of basil medicinal plant (ocimum basilicum l.)

the autotetraploidy was achieved in basil using tip meristem treatment of seedlings with various concentrations of colchicine solution (0, 0.05, 0.1, 0.2, 0.5 and 0.75% (w/v) ph = 6). a significant increase in the essential oil content was observed in tetraploids as they carry the potential of productivity of 69 % more oil over the diploids. a field experiment was conducted to investigate the effect of autotetraploidy on some such quantitative and qualitative characteristics of basil as: leaf area, fresh and dry weight, chlorophyll content, leaf width and thickness, the number of latral branches, cluster number and length, plant height, flower and stem diameter, as well as period of flowering. this study demonstrated that autotetraploidy significantly increased dry and fresh weight, chlorophyll content, leaf width and thickness, stem diameter and number of lateral branches. on the other hand increase in ploidy level caused decrease in leaf length, cluster number, seed germination percentage and rate, as compered with diploid plants