PHYSIOLOGICAL CHARACTERIZATION OF HALOPHYTIC WEEDS GROWING IN SALINE AND NON-SALINE REGIONS OF PAKISTAN

The difference in salt tolerance mechanism of halophytes with that of glycophytes has already been underlined in the plants of saline land. Present investigation deals with five wild plant species: Solanum surattense Burm. f ,Cenchrus ciliaris L, Aerva javanica (Burman f.) A. L. Juss. Ex Schultes, Peganum harmala L and Chrysopogan aucheri Boiss.  collected from Khewra salt range (EC=2.3 dSm-1 and pH: 8.5) to study the physiology of their salt tolerance in comparison with that of plants of same species collected from non-saline soil of Rawalpindi (EC: 0.31 dSm-1; pH: 7.4). Differences exist between plants of saline soil with respect to accumulation of t-zr (trans zeatin riboside), ABA (abscisic acid), SOD (superoxide dismutase), POD (peroxidase), proline, glycine betaine and sugar. The ABA concentration of plants from saline soil was higher in the leaves and roots than that of the plants of non saline area. Proline and glycinebetaine in Chrysopogan aucheri (CaKH) from saline soil was significantly higher than other plants of saline soil. All the plants exhibited higher ABA/t-zr ratio as compared to plants of non-saline soil. It is infrared that the ratio of ABA/t-zr and the antioxidant activities of enzymes can serve as index for salt tolerance.