Author : Nguyen Thi Thanh Tuyen

Summary : The growth response of three varieties of rice (Oryza sativa L.) namely, IR8, PB76-TB188 and C4-63G to salt stress was studied. Rice plants at one month old were treated with sodium chloride at various concentrations: 0, 0.1, 0.2 and 0.3 percent (weight-volume basis). The contents of nucleic acids and protein per gram of fresh weight and dry weight, respectively, were measured weekly after salination. The RNA and protein contents in leaves of the three varieties decreased with age, in all treatments, including the control. The reduction of these two compounds was identical in all three varieties and occurred immediately after salination. On the other hand, the DNA content increased in plants grown at all levels of sodium chloride up to the second week after the salt was added and then decreased. It is possible that the RNA and protein contents in the leaves were more sensitive to salinity than DNA.