ABSTRACT
Rice (Oryza sativa L.) cells, grown under a continuous stress of 1.5% NaCl, produced a homogeneous mass of dry, compact, nodular callus with high regeneration potential, typical of embryogenic cultures. When transferred and subcultured in conditions without salt, the pre-adapted cells underwent several changes, leading to the formation of heterogeneous populations that comprised different cell types. This newly formed callus, in the 6-month period without salt stress, resembled cell populations of the untreated cultures. These cells are characterized by fast growth, high water content, friable texture, high salt sensitivity and low culture response. They also produce a protein pattern in the SDS-PAGE analysis, that differs from that of cells cultured under the continuous salt stress. This observation indicates that different salt stress regimes induced different responses in the cultured cells in rice.
Subject(s)
Oryza/drug effects , Sodium Chloride/pharmacology , Adaptation, Physiological , Drug Tolerance , Oryza/cytology , Oryza/physiology , Phenotype , Plant Proteins/biosynthesis , Regeneration/drug effects , Regeneration/physiology , Sodium Chloride/administration & dosageABSTRACT
Three main types of callus have been selected from seeds of salt marsh grass(Puccinellia limosa (Schur.) Holmbg.) subcultured on Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid and kinetin. Callus type I differentiated only occasionally. Callus type II produced roots but no shoots under all tested culture conditions. Both green (47 %) and albino plants have been obtained from the embryogenic callus type III. Callus type III was divided into two subtypes (greening and non-greening) according to the presence or absence of green spots. Separated greening embryogenic callus gave up to 87 % green plants, whereas non-greening callus produced only 4 %.
