Seed Priming Lab Report

MATERIALS AND METHODS
EXPERIMENTAL DETAILS AND SEED PRIMING
Experiment was conducted in laboratory of the department of Vegetable Science, Punjab Agricultural University, Ludhiana to evaluate the effect of seed priming treatments and soaking durations on activity of antioxidant enzymes and isozyme banding pattern of these enzymes of okra (Abelmoschus esculentus L.) viz. Punjab 8. Seed priming treatments included T1 (hydro-priming), T2 (osmo-priming with 5% Polyethylene glycol), T3 (osmo-priming with 10% Polyethylene glycol) and T4 (priming with distilled water). Seeds were fully immersed in priming solutions for soaking durations of 6, 12, 18, 24, 30, 36, 42 and 48 hours. Dry seeds were considered as control treatment that was 0 h soaked. To avoid fungal growth during the priming process, a fungicide Captan (2g/L) was added to the priming solutions. At the end of each priming period, the seeds were air dried at room

The extract was centrifuged at 20,000 rpm for 10 minutes at 4°C, the clear supernatant being taken for enzyme assay.
Assay
Catalase was assayed at 37°C in a reaction mixture containing 1.9ml of 0.1M sodium phosphate buffer pH 7.0 in 0.1ml of enzyme extract. The reaction was initiated by adding 1ml of H2O2 to the reaction mixture. The rate of decrease in absorbance at 240 nm was measured at 10 second intervals for 1 min. The specific activity of CAT was expressed in terms of unit of H2O2 decomposed per min per mg of protein.
Peroxidase (Shannon et al., 1966)
Extraction
Sample (0.2g) was homogenized in 2ml of cold (4oC) 0.1M Tris-HCl buffer containing 1% (w/v) insoluble PVP, 1mM EDTA and 10μM β-mercaptoethanol. The extract was centrifuged at 20,000 rpm for 10 minutes at 4°C, the clear supernatant being taken for enzyme assay.