A doctoral thesis at the College of Agriculture at Basra University discussed (the effect of chitosan and ascorbic acid on ex vivo multiplication of kumquat and its genetic stability) The thesis included the researcher (Hazem Sultan Safana) The effect of adding BA to the food media was studied at concentrations (0, 0.5, 1.5, 2.5, 3.5, 4.5 and 5.5) mg.L-1 with 40 mg.L-1 adenine sulfate and quinosan (1, 2, and 3) mg.L-1 and acid. Ascorbic acid with concentrations (1, 2, 3 and 3 mg L-1 and the effect of naphthalene acetic acid) at concentrations 1, 2, 3, 4 and 5 mg L-1. Random DNA polymorphism (RAPD) technology was used to detect the genetic differences of the plants formed and the mother plant under study, in order to facilitate the partial study of the stages of propagation. The thesis aims to identify Employing ex vivo cultivation technique in tissue propagation of kumquat and obtaining plants in large numbers and in a short time from different plant parts. Determining the optimal concentration of natural compounds and growth regulators added to the nutrient medium in the multiplication and rooting of branches and acclimatization of plants. The thesis concluded the possibility of successfully adopting the tissue culture technique in the tissue propagation of kumquat and obtaining the required numbers by adopting the studied factors that showed a significant response during all stages of the study according to the conditions of the experiment. The study showed the efficiency of the RAPD technology and its effectiveness in detecting the proportions of distance and similarity between the mother plant and the tissue-propagated plants with the help of the eight primers that proved successful in detecting similar bands between the studied samples, thus confirming their genetic matching. The thesis recommended the use of plant tissue culture technology to establish a tissue farm of kumquat plants, which opens wide horizons for expansion by using other growth regulators or their like and with different combinations to increase the rates of vegetative characteristics in quantity and quality. And expanding in the future by conducting genetic matching tests using other molecular markers and for other primers such as SSR and YFILB markers.