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Start Over Coverage 9-16

2. Effect of drought on subterranean clover. 2. Genetic variability of photosynthesis, transpiration and stomatal conductance

Creator:
Vadell, J. and Medrano, H.
Format:
print
Type:
model:internalpart and TEXT
Language:
Multiple languages
Description:
The CO2 assimilation rate the transpiration rate (E), the stomatal conductance (gg), C index and the instantaneous water use efficiency of attached leaves háve been estimated in sixteen cultivars of subterranean clover (Trifolium subterraneum L.) fíeld growing plants, both irrigated and subjected to water stress, during latě spring in Mallorca, Spain. Variability among the genotypes with regard to the and other related parameters was highly significant for tiie irrigated plants. Drou^t promoted a marked decrease in both gg and ®ven when the relative water content of leaves was only slightly decreased. For water-stressed plants, genotypic variability in E and C index was also statistically significant. However, variability among the genotypes with regard to gg and was no longer evident under drought. The C index might represent a valuable parameter for evaluation of the genotypic responses of plants to drought.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. Observations of bipolar outflows

Creator:
Bally, John
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations and bipolar outflows
Language:
Czech
Description:
Energetic outflows, often colliinated into two oppositely directed jets, are frequently found to be associated with new-born stars still buried in their parent molecular clouds. Millimeter wavelength observations of molecular transitions of species such as CO have shown that the cold molecular component of the outflows has velocities up to 60 km.s^-1 with a total mass ranging between 0.01 Mq for low mass stellar sources to over 100 Mq for flows having several massive stars at their core. Optical and near infrared observations reveal a hot (over 10^3 Kelvin) flow component exhibiting velocities in excess of 300 km s^-1. Although some jets associated with low luminosity sources, such as HH-34, exhibit a very high degree of colliination, the structure of most massive outflows is complicated, appearing "bipolar" only in low angular resolution observations. At high resolution, many sources exhibit lumps, oscillations, or flow in more than just two directions. In this talk I will review millimeter-wave as well as some near-infrared and optical observations of this impotant phase of stellar birth.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public