| Effect of salt stress on germination and seedling growth
of wheat cultivars. S.M. ALAM, A.R. AZMI and S.M. NAQVI Atomic Energy Agricultural Research Centre, Tando Jam, Sind, Pakistan Soil salinity is one of the most important problems in the arid and semi-arid zones causing significant decreases in soil productivity. The accumulation of salt in irrigated soils reduced the germination, growth and eventually the crop yield. Soil salinity both decreases and delays germination in wheat, barley and triticale (BISHNOI & PANCHOLY 1980) and differences in salt tolerance of various cultivars have been reported (JANA et al. 1980, MAAS & HOFFMAN 1977). In the present investigation, an attempt was made to determine the effect of different concentrations of NaCl and Na2SO4 mixed together on germination and seedling growth of wheat genotypes to identify their salt tolerant and salt sensitive behaviours. Materials and Methods A laboratory experiment was conducted to ascertain genotypic response of 9 wheat genotypes to salinity during germination and seedling growth. One hundred seeds of each of these genotype were subjected to different concentrations of NaCl and Na2SO4 (0.00, 0.2, 0.4, 0.6, 0.8 and 1.0%) and were allowed to germinate in darkness on filter paper in petri dishes soaked in a solution of the respective salt concentration for 120 hours at 26C. A completely randomized design with four replication was used in this experiment. Ten plants from each treatment and the control were measured for shoot and root length to the nearest millimeter. The total number of seeds germinated were also counted. The data were tabulated and presented in Table 1-3. Results and Discussion i) Germination. It is obvious that each increment of 0.2% salinity concentration significantly reduces. The germination percentage of all the genotypes. It is assumed that in addition to toxic effects of certain ions, higher concentration of salt reduces the water potential in the medium which hinders water absorption by germinating seeds and thus reduces germination (MAAS & NIEMAN 1978). The genotype LU-26-S had shown significantly higher salt tolerance (87.8%) than all other genotype at the highest salinity level 1.0%. The most salt sensitive genotype was Sonalika with 53.2 percent germination. The differential genotypic response to salinity at germination stage has also been reported (HELAL & MENGEL 1981, JANA et al. 1980). |
| --> Next |