Cress (Lepidium sativum) seed germination and beta- galactosidase enzyme production regulation in re
- Details
- Category: Biological Sciences
- Published: Monday, 15 February 2016 02:00
- Written by Wafaa Zaid Al-Shamaileh,وفاء زيد الشمايلة
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Cress (Lepidium sativum) seed germination and
beta- galactosidase enzyme production regulation
in response to different abiotic factors
In this study, Lepidium sativum seeds were subjected to different abiotic stresses to evaluate the seed performance and β-galactosidase specific activity under controlled conditions(dark and 25 ˚C) and in response to the effect of temperature (20, 30 and 35 ˚C), salinity (NaCl; 50, 100, 150 and 200mM), osmotic stress (PEG-8000; -0.05, -0.09, -0.15, -0.22 and -0.31 MPa), heavy metal (Cd; 5, 20, 50 and 80ppm) and light quantity (3.4, 34 and 340 µE) for short interval periods involved 12, 16, 18 and 24 hour for each specific treatment. The results indicated that the reduction of germination percentage was greater for elevation temperature (30 and 35 ˚C) reached to marked delay of germination which starts after 24h of 35 ˚C showed thermo-inhibition. The severity of salinity stress was appeared as concentration and time of exposure which showed the higher effect on seed germination start after 50 mM NaCl and appear strongly with increasing the concertation that lead to delay the germination or even inhibit the germination totally which start late after 16 or 18 h of incubation. Osmotic stress had negative effect with decreasing the water potential that affect the early events of germination more than that the later one. Cadmium chloride treatment sharply reducing the germination, in particular at the early time point of incubation even at low concertation (5ppm). Light quantity had positive effect with increasing the germination at all time of germination events with increasing the light intensities.
In parallel to the changing in germination percentage, β-galactosidase specific activity and seed protein content changed in the same manner in response to the different abiotic stresses.
Further investigations are required to evaluate the effect of abiotic stresses, those include antioxidant enzymes activities, non-enzymatic antioxidants levels and plant hormones influence during Lepidium sativum seed germination.