Determination of the effective of chemical mutagenesis using sodium azide to improvement of vegetative growth and flowering characteristics in Helichrysum bracteatum L. plant

Abstract

This study were carried out on Helichrysum bracteatum L. plant at the Experimental nursery of the Ornamental Hort. Dept., Fac. Agric., Cairo Univ., Giza, Egypt, during the two successive seasons (2014/15 and 2015/16). The aim of this study was to investigate the effect of on some vegetative and flowering parameters and anatomical structure of leaves and flowers. Seeds of H. bracteatum L. were exposed to four concentrations of (0.05, 0.1, 0.2 and 0.3%) of sodium azide (NaN3) solution for six hours; one set of seeds was kept without sodium azide treatment (untreated) to act as control. The obtained data revealed that the low concentration of sodium azide (SA) increased plant height, number of leaves/ plant, stem diameter (cm) number of flowers, flowers fresh weight (g)/plant and flowers dry weight (g)/plant in M1 and M2. The ratio of chlorophyll (a and b) showed a markedly decrease as a result of increasing sodium azide concentrations. On contrary, in case of carotenoids showed a markedly increase as a result of decreasing sodium azide concentrations. Were obtained on many morphological mutants in flowers through two generations. Some parameters of anatomical structure of leaves and flowers and to confirm the stability of some of the mutations were obtained during the second generations.