استحداث خلايا متحملة للملوحة من نبات البزالياL.Pisum sativum باستخدام تقنية زراعة الانسجة

Abstract

Explants existed which taken from plantlets grow from culturing seeds of Pisum sativum L. in vitro were cultured on MS medium supplemented with different growth regulators. Callus was then exposed to different concentrations of salt mixtures, namely NaCl, CaCl2 and MgCl2 in a ratio of 2 : 2 : 1 at concentrations of 0, 25, 50, 75, 100 and 125 mM add to culture medium. Results showed a significant differences between callus of the explants in their response to salinity levels. Callus fresh weight decreased with increasing salinity, the completely inhibited at 125 mM, which considered as inhibitory (lethal) 100% level and the concentration of 100 mM was the sub lethal . Selection for salt tolerance then carried out using the latter concentration. Selection was carried out using two methods, indirect (stepwise) by gradual increase up to 100 mM, ,or direct by sub culturing on 100 mM for four subcultures, then cultured on salt free medium for four subcultures . Results showed that the leaf was significantly better than stem in its callus fresh weight after four subcultures on salt free medium. Callus induced initially from the stepwise selection method was more superior than the direct method since the first produced more callus fresh weight. Selected calli were examined for their ability to tolerate 0 – 125 mM. Results showed that the callus fresh weight induced from leaf was significantly higher. A sharp reduction in callus fresh weight was recorded with increasing salt levels.