The Douglas fir has been cultivated in Europe since the mid-19th century, but its artificial regeneration leads to a low yield of seedlings. It could be improved by prolonged pre-sowing treatment (cold stratification seeds) or early shading sowings, so that their effect on five seed lots and emergence growth seedlings were analysed. One lot came from USA; four Czech Republic. germination capaci...

Demand for butterfly milkweed ( Asclepias tuberosa L.) has increased in recent years. However, seed production practices are not well-defined. We partnered with a wildflower producer to investigate the effects of weed barrier cloth, plot shading, mature follicle harvest timing, and dry–cold stratification on germination. Weed cloth had no impact production. shading decreased number seeds produc...

construction and operation of dams have two main effects on streams. at first it increases detention time and then leads to thermal stratification. changing of water quality is the result of these effects and the outflow has different physical, chemical and biological characteristics from inflow.in this study thermal regime in proposed bakhtyari reservoir was simulated with ce-qual-w2 model. th...

[1] Water column stratification increased at climatic transitions from cold to warm periods during the late Quaternary and led to anoxic conditions and sapropel formation in the deep eastern Mediterranean basins. Highresolution data sets on sea-surface temperatures (SST) (estimated from U37 k0 indices) and dO of planktonic foraminifer calcite (dOfc) across late Pleistocene sapropel intervals sh...

Native plants of the Sahara are remarkably resistant to prolonged droughts and important sources forage, food, medicine. Their regeneration from seeds after strong anthropogenic disturbances is a challenging step toward their conservation mitigate desertification. We studied germination responses 43 dominant native species desert that could be propagated for future ecological restoration projec...

BACKGROUND Arbutus unedo is a valuable Mediterranean shrub as an ornamental plant as well as fruit tree. Fresh fruits of A. unedo are a good source of antioxidants, of vitamins C, E and carotenoids and also are characterized by the high content of mineral elements. MATERIALS AND METHODS The effects of gibberellic acid (GA3) and cold stratification (CS) on seed germination performance were inv...

Dormant Arabidopsis seeds require stratification and light for germination. To study gene expression during establishment, maintenance and release of dormancy, various Arabidopsis ecotypes that are different in their degree of dormancy were investigated; three nsm mutants that lack the stratification-dependency, and the precocious germination and reduced dormancy of the abi3-1 mutant (insensiti...

Perfect timing of germination is required to encounter optimal conditions for plant survival and is the result of a complex interaction between molecular processes, seed characteristics, and environmental cues. To detangle these processes, we made use of natural genetic variation present in an Arabidopsis (Arabidopsis thaliana) Bayreuth × Shahdara recombinant inbred line population. For a detai...

Some HVAC systems save energy by creating stratified air temperature distributions in which the occupied lower regions are cooler and the upper regions warmer. Comfort standards prescribe a 3°C limit to vertical stratification, independent of where the mean temperature is relative to the comfort zone. This paper evaluates thermal comfort in stratified environments using a model developed to pre...