الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 279 |  |  |
| | | from | 279 | | |
Abstract
This study aimed : This study was carried out in the Laboratory and glasshouse of Agric. Bot. Dept., Fac. of Agric., Mansoura Univ., Egypt, during the growing season (from 2012 to 2014) to evaluate the effect of priming time on two rice cultivars namely,‘Giza178’ and ‘Sakha 101’ and to recommend optimum priming protocols under different levels of osmatic potential using osmotic substances PEG (drought) and comparing these with NaCl during germination and investigate the effects of priming rice grains in varying concentrations of chemicals i.e. salicylic acid or ascorbic acid and signaling molecules such as hydrogen peroxide and nitric oxide in upon their germination, seedling growth, some aspects of metabolism and certain botanical characters in seedling.The most important results achieved are summarized as follows: •First Experiment : Determine the optimal time duration of rice grains priming. •Second experiments : The effect of unprimed and different priming methods.Third Experiment: Effect of some priming agent on physiological and anatomical parameters of rice cultivar (Giza 178) under normal and NaCl or PEG.Conclusion Under the conditions of these experiments, it may be concluded that for minimize the harmful effects of NaCl (salinity) and PEG(draught) (up to - 8bars) and enhancing seed germination and seedling growth of rice plant, it is recommended to priming the grains for 48 hours before sowing in salicylic acid at 100 ppm or ascorbic acid at 50 ppm H2o2 at 50 mM and No at0.1 mm.