POLYETHYLENEGLYCOL (PEG) INDUCE CHANGES IN GERMINATION, SEEDLING GROWTH AND WATER RELATION BEHAVIOUR OF WHEAT UNDER SALT STRESS CONDITION

Abstract

An experiment was conducted at Laboratory of Department of Agronomy, Sher-eBangla

Agricultural University (SAU), Sher-e-Bangla Nagar, Dhaka-1207 during the period from October 2016 to December 2016. A set of experiment was conducted in three different experiments. The experiment was laid out in a Completely Randomized Design (CRD) with five replications. Four wheat genotypes namely- ESWYT 5, ESWYT 6, ESWYT 7 and BARI gom 28 were used as test crop and different priming chemicals such as PEG, salt (NaCl) and distilled water were utilized for osmo and hydro priming. The data on germination parameters of wheat like germination percentage and growth parameters like root length, shoot length, dry weight and vigour index. Data were analyzed using a computer software MSTAT-C. The significance of difference among the treatments means was estimated by the Least Significance Difference (LSD) at 1% level of probability. The first experiment was carried out to find the effect of different concentration of PEG on germination and growth behavior of four wheat genotypes (ESWYT 5, ESWYT 6, ESWYT 7 and BARI gom 28) without any stress condition. It was found that ESWYT 5 showed the highest germination rate (95.30%), shoot length (168.20 mm), root length (158.30 mm), shoot dry weight (0.0522 mg), root dry weight (0.0432 mg), relative water content (95.05%), water retention capacity (16.18) and vigour index (311.30) with primed seeds with 10% PEG solution for 12 hours. The second experiment was conducted to optimization of pre-sowing priming time on the germination and growth behavior of wheat genotypes. It was observed that ESWYT 5 with 10% PEG primed seeds for 9 hours gave the highest germination rate (83.33%), shoot length (181.1 mm), root length (145.0 mm), shoot dry weight (0.0536 mg), root dry weight (0.0432 mg), relative water content (91.45%), water retention capacity (19.94) and vigour index (272.3). In the third experiment germination and growth behavior of primed seeds of wheat genotypes (ESWYT 5, ESWYT 6 and BARI gom 28) under salt (NaCl) stress condition were evaluated. It was observed that highest germination rate (93.81%), shoot length (157.80 mm), root length (124.6 mm), shoot dry weight (0.037 mg), root dry weight (0.0414 mg), relative water content (89.13%), water retention capacity (22.32) and vigour index (264.7) were obtained from ESWYT 5 under primed seeds placed without salt. But under salinity stress, the highest germination rate (87.62%), shoot length (154.20 mm), root length (118.50 mm), shoot dry weight (0.0349 mm) and root dry weight (0.0393 mg), relative water content (85.61 %), water retention capacity (21.40) and vigour index (238.9) were achieved from ESWYT 5 under primed seeds placed with 5 dsm