Severe drought stress is the prolonged low rainfall that limits rangeland biomass production. Due to drought severity in Cholistan rangeland, an experiment on seed germination, biomass production and gaseous exchange activity of Aeluropus lagopoides and Ochthochloa compressa against induced drought stress by Polyethylene Glycol (PEG-6000) was conducted. Seeds germinated using a completely randomized design (CRD) at T1=0, T2=10% and T3=20% PEG-6000 concentrations. Data was analyzed by simple linear correlation and CR design. Results showed that PEG-6000 significantly affects germination, biomass production and plant physiology. Seed germination at treatments T1 was 78% with 0.873 coefficient of correlation (R-squared) and minimum was in T3 (20% PEG-6000) which was germination 44% with R-squared 0.78 in O. compressa.  The highest seed germination in A. lagopoides was at T1 72% with 0.826 coefficient of determination (R-squared) and the minimum was at T3 40% with R-squared 0.74. The results also showed that PEG-6000-induced drought stress negatively correlates with physiological and morphological parameters. Conclusively PEG-6000 induced drought stress significantly lower the seed germination and biomass production. Various plants adapt different strategies for coping with drought stress. Exploration of such strategies helps us better understand sustainable range management.

Keywords: Aeluropus lagopoides, Biomass, Ochthochloa compressa, Gaseous exchange Photosynthesis, Sustainable range management