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Seven barley (Hordeum vulgare L.) cultivars tested varied greatly in their responses to root medium salinity (electrical conductivity of 3, 5, 10, 15 and 20 dS m-l). Plant growth was relatively more adversely affected than seed germination. Dry/fresh mass ratio increased at higher salinity levels in all barley cultivars indicating reduced water uptake. Higher K/Na ratio in plant shoots compared to that in the root medium solution indicated selective uptake of K that seems to be among processes involved in tolerance of cultivars to salinity stress.Barley is known to be salt tolerant crop (e.g. Norlyn and Epstein 1982), however large variation exists among its cultivars (Bhatti et al. 1976). The purpose of the present study was to screen germplasm of barley collected from arid and semi-arid areas of Pakistan for salt tolerance.The effect of different salinity levels [electrical conductivity (E.C.): 3, 5, 10, 15 and 20 dS m-q on seed germination and growth of seven barley cultivars (Table 1) was studied. Salinity levels of 5 to 20 dS m -1 were prepared by the addition of Na~SO 4, CaCI 2, MgCI2, and NaC1 in ratio of 10:5:1:4 on equivalent basis (Qureshi et al. 1977) to the Hoagland nutrient solution (Amon and Hoagland 1940) with E.C. of 3 dS m -1 used as control. Ten seeds of each cultivar were placed in Petri dishes on filter paper soaked with 5 ml of respective solution, three replicates per treatment.

Aqueous leaf extract of common lambsquarters (Chenopodium album L.) was evaluated alone or in combination with NaCI salinity tbr its influence on germination, seedling growth and contents of Na, K, and Ca by shoots and roots of wheat. The leaf extract and NaC1 alone or in combination did not have any significant effect on germination, but the shoot and root lengths of seedlings and their dry weight decreased significantly by the treatments. Root growth was affected more than the shoot. The combination of leaf extract and NaCI drastically reduced the growth more than the separate effects of these stress treatments.The incorporation of leaf extract in the growth media decreased the content of Na by shoot, whereas the contents of K and Ca increased. NaCI treatments in combination with leaf extract increased the content of Na. Similar increases were observed for K and Ca in shoot, while these nutrients were increased in roots compared to control.

Climate change is emerging phenomena and causing frequent drought which lead to scaricity of water, which ultimately nagetively affecting wheat (Triticumaestivum L.) yield all around the world. The aim of this study was to explore the potential deought tolerant wheat genotypes for candidate genes exploration. This study was conducted during the year 2014-2015 at Plant Physiology Division, Nuclear Institute of Agriculture (NIA) Tandojam. The six wheat genotypes (cv. MT-1/13, MT-2/13, MT-3/13, MT-4/13 Chakwal-86 and Khirman) were investigated for their response at germination and seedling stage under different water stress treatments (0, -0.5, -0.75 and -1.0 MPa) in controlled conditions. The results of experiments with reference to genotypes revealed that genotype Chakwal-86 shows maximum seed germination (82.58 %), while the genotype Khirman shows maximum shoot length  (7.23 cm), root length  (15.1 cm), shoot fresh wt. (5.85 g 10-1shoots), root fresh wt.  (3.45 g 10-1roots), shoot dry wt. (1.33 g 10-1shoots), root dry wt. (0.69 g 10-1roots). Among the genotypes tested Khirman and MT-4/13 are the tolerant genotypes had the potential to perform better under drought conditions, whereas  MT-4/13 and Chakwal-86 were moderate tolerant under water stress conditions. Moreover, the genotypes i.e. MT-1/13 and MT-2/13 are the sensitive genotypes under drought environment. It is concluded from present in-vitro studies that osmotic stress significantly reduced the seed germination shoot/root length fresh and dry weight in all six wheat genotypes. The maximum reduction was found at higher osmotic stress induced by PEG-6000 (-1.0 MPa) significantly.

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