Experimental Setup: The experiment was conducted during October 2014 to December 2014 with collected Sunflower seeds and NaCl from the University. This experiment consists of two factors i.e varieties (BRAC HySun 33, BARI sunflower-2 & KU SL- 1) and five levels of salinity (Control, 4, 8, 12, 16 dS m-1). The experiment was laid out in a Completely Randomized Design (CRD) with five replications. Required amount of sodium salt (NaCl) was estimated and added to prepare respective salt solution. Germination experiment was conducted by petridish method by using distilled water and saline soil solution of different concentration.
Data collection: Data were collected and calculated on germination percentage (%), germination energy (%), germination capacity (%), germination speed (%), root length (cm), shoot length (cm), seedling growth rate (mg/day), seedling vigor index. Data were collected randomly from five seedlings of each Petridis for root and shoot length measurement.
Germination rate: Percentage of seed germinated at certain period
Germination energy: Percentage of seeds germinated at 72 h (Bam et al., 2006)
Germination capacity: Percentage of seeds germinated at 168 h (Bam et al., 2006).
Speed of gemination (%) = Number of seeds germinated at 72 h / Number of seeds germinated at 168h x 100
Seedling vigor index = (Average shoot length +average root length)× germination percentage
Seedling growth rate: Amount of dry matter production (g) per unit time is seedling growth rate:
Seedling growth rate = W2 - W1 / T2 - T1
Where, W1 and W2 are initial and final dry weight of plant sample, respectively; T1 and T2 are initial and final time, respectively.
Statistical analysis: The recorded data were analyzed statistically using MSTAT-C software. Analysis of variance (ANOVA) technique was employed to test the overall significance of the data. The mean differences were adjudged by Duncan’s New Multiple Ranges Test (Gomez and Gomez, 1984).