somatic embryogenesis is a new approache to plant mass in vitro propagation. this method influences by elements and their components in medium. in order to investigate the effects of different media and it,s role on somatic embryogenesis of carrot, a cbd experiment with four replications (including 12 treatments) was conducted. to do this, carrot petioles (with 1 cm dimension) in induction phas...

The Arabidopsis male sterility1 mutation results in mature anthers that are devoid of pollen. Meiosis and early development progress normally; however, after microspore release, the microspore cytoplasm and tapetum become abnormally granular and vacuolated, and degeneration occurs. Pollen wall development is seriously affected; primexine formation within the callose wall appears to occur normal...

The pollen cell wall is important for protection of male sperm from physical stresses and consists of an inner gametophytederived intine layer and a sporophyte-derived exine layer. The polymeric constituents of the robust exine are termed sporopollenin. The mechanisms by which sporopollenin is anchored onto microspores and polymerized in specific patterns are unknown, but the primexine, a trans...

The development of the pollen grain wall in Xiphidium coeruleum (Haemodoraceae) was studied using TEM and cytochemical staining techniques. Microsporocyte ontogeny initiates with the degradation of the cellulosic cell wall and subsequent deposition of a thick callosic cell wall. Following callose deposition, successive meiosis occurs, resulting in a tetragonal tetrad of microspores. during meio...

one of the important methods of plant propagation in large scale so as genetic manipulation and artificial seed production is somatic embryogenesis technique. the obtained results from this methods related to different factors including condition of culture medium. therefore, the aim of this study conduction were determining the role of molybdenum during carrot petiole somatic embryogenesis. at...