ENHANCEMENT OF GERMINATION, SEEDLING GROWTH, WATER RELATION BEHAVIOR OF WHEAT THROUGH OSMO AND HYDRO PRIMING UNDER DROUGHT STRESS CONDITION

Abstract

A laboratory experiment was carried out at the central laboratory of Sher-e-Bangla Agricultural University Dhaka-1207 during the period from December 2019 to February 2020 to find out the effect of various Mannitol concentrations on the germination, seedling growth and water relation behavior of wheat under drought stress condition. This study consisted of two different experiments. Mannitol was used as priming agent and PEG (Polyethylene glycol) was used for inducing drought stress. Ethanol was used as surface sterilizer of wheat seeds. The data on different parameters were recorded for analysis the result of this experiment. For the first experiment four levels of mannitol such as 1%, 2%, 3% and 4% were used for osmopriming and water was used for hydropriming. Seeds primed with 2% mannitol gave the best results on studied parameters. Results revealed that the seed primed with 2% Mannitol for 9 hours showed the highest germination rate (98%), shoot length (162.3 mm), root length (183.3mm), shoot dry weight (12.2 mg), root dry weight (13.5 mg), fresh weight (354.0 mg), water saturation deficit (29.75), relative water content (70.25%) and vigor index (338.69). Seeds without osmo priming and hydropriming showed lowest results in studied parameters. In the second experiment, 2% mannitol primed (9 hours) seeds of wheat with and without drought (PEG) stress condition was evaluated. The drought stress level was induced by 0%, 5%, 10%, 15% and 20% PEG solution. It was observed that the genotype BARI Gom 31 primed with 2% mannitol for 9 hours seeds placed without drought (control) gave the best performance on studied parameters but under drought stress, the highest germination rate, shoot length, root length, shoot dry weight and root dry weight, fresh weight, relative water content and vigor index were achieved from primed seeds placed on 5% PEG where primed seeds placed on 20% PEG induced drought condition showed lowest results in respected parameters. From the result of the study, it was revealed that seeds primed with 2% mannitol for 9 hours showed the best results compared with water primed and non-primed seed under drought stress condition.