this research was carried out to investigate allelopathic effect of peganum harmala on seed germination of bromus tectorum. aboveground and underground tissues of peganum harmala in addition to its seeds were collected from bijar rangelands. collected materials of root, leaves, stem, seeds and a complex of mentioned parts were dried and powder. the research was performed at the greenhouse condi...

this experiment was conducted in germinator in order to study the effects of water potential on seed germination, rate of germination and seedlings growth of four medicinal plants (coriandrum sativum, plantago psyllium, discorinia sophia and portulaca oleracea). four water potential inclouding distilled water as control (0), -0.37, -0.59 and –0.81 mpa which made by different salts (nacl, cacl2 ...

Musk thistle is an invasive weed that is widely distributed throughout much of North America, including grasslands in temperate climates of the midwest USA. A series of laboratory and greenhouse experiments were conducted to determine the effect of various environmental factors on germination of musk thistle seeds. In temperature-fluctuation experiments, seed germination was greater than 65% in...

Germination provides many potentially unrecognized sources of variation in the regeneration niche. In this study we relate germination requirements and seed size for 16 species of pioneer trees to microclimatic conditions present in gaps in semi-deciduous rain forest in Panama. We found that, whereas increased duration of direct irradiance can be an effective indicator of the presence of a cano...

Salinity is one of the environmental factors that have a critical influence on the germination of seeds and plant establishment. Salinity affects imbibition, germination and root elongation. In this study, the germination characteristics of Matricaria comomilla and Thymus deanensis were studied. The purpose of this study was to investigate the effect of salinity on germination of these species....

The physiological process of germination depends on several environmental factors such as temperature, water potential, light, nutrients and smoke. Water and temperature are determinant factors for seed germination. Both factors can, separately or jointly, affect the germination percentage and germination rate. The effect of temperature on germination and water potential on germination canoften...