Water deficit effects on morpho-physiologicals parameters in durum wheat

Various morpho-physiological characters related to the water deficit (relative water content, rate water loss, stomatal density, stomatal resistance), were studied at five durum wheat genotypes under two hydrous conditions. The relationship between traits and adaptative strategies develops by each genotype have been described. Results obtained show that been present an appreciable variability intraspecific for the morpho-physiological parameters related to the adaptation to the water deficit. Tolerance of this condition has estimated through for relative water content who is explained by morpho-physiological parameters. Finally, the contribution of the morpho-physiological parameters in the adaptation of the durum wheat depends closely on the intensity of the hydrous deficit.Keywords: durum wheat, water deficit, adaptation, morphological parameters, physiological parameter

Effect of salt stress on some physiological parameters in Atriplex halimus L.

The impact of salinity applied for five weeks followed two provenances of Atriplex halimus L. harvested from Oran (Algeria coast) and Ain Dheb (high plateaus west of Algeria). The analyzed parameters are physiological from the leaves of young plants grown in a greenhouse stored in air-conditioned glass. Two types of salt stress are imposed on plants from the 165th day after sowing for a batch CaCl2 + NaCl to 300 meq and 600 meq.l-1and for the other batch to undiluted water sea with a frequency of watering every other two days. The results of water indicators such as the relative water content (RWC or TRE) showed some fluctuation during the five weeks under the two types of stress. Transpiration (water loss from the excised leaf or RWL) measured after 30, 60 and 120 min at the end of the period of application of stress presents a decline in both sources and types of stress. In addition, the stomatal resistance showed considerable variability for both sources and the type of stress.Keywords: A. halimus L., salt stress NaCl + CaCl2, Seawater, RWC, sweating, stomatal resistance

Water and physiological responses of Okra (Abelmoschus esculentus (L.) Moench) under saline stress grown on a bentonized substrate

In many arid and semi-arid regions of the world, Salinity has become an important problem for agricultural production. The objective of this study was to evaluate the effect of different treatments of NaCl (Control, 100 mM and 300 mM) for 7 days, on young okra plants (Abelmoschus esculentus), grown in two types of substrate with bentonite (B) 7% and without bentonite (WB) under controlled greenhouse conditions. The results showed that the two factors (salinity and bentonite) imposed in our study have a significant effect on the water status estimated by RWC, RWL and DHS in addition of the accumulation of the osmoregulator (proline, soluble sugars).Keywords: okra, bentonite, salinity, water parameters, biochemical parameter

Intraspecific Variation in Pinus Pinaster PSII Photochemical Efficiency in Response to Winter Stress and Freezing Temperatures

As part of a program to select maritime pine (Pinus pinaster Ait.) genotypes for resistance to low winter temperatures, we examined variation in photosystem II activity by chlorophyll fluorescence. Populations and families within populations from contrasting climates were tested during two consecutive winters through two progeny trials, one located at a continental and xeric site and one at a mesic site with Atlantic influence. We also obtained the LT50, or the temperature that causes 50% damage, by controlled freezing and the subsequent analysis of chlorophyll fluorescence in needles and stems that were collected from populations at the continental trial site

Looking for interaction: quantitative measurement of research utilization by Dutch local health officials

Background: In the Netherlands, local authorities are required by law to develop local health memoranda, based on epidemiological analyses. The purpose of this study was to assess the actual use of these epidemiological reports by municipal health officials and associated factors that affect this use.Method: Based on a conceptual framework, we designed a questionnaire in which we operationalized instrumental, conceptual, and symbolic use, the interaction between researchers and local health officials, and four clusters of barriers in this interaction process. We conducted an internet survey among 155 Dutch local health officials representing 35% of all Dutch municipalities. By means of multiple regression analyses, we gained insight into the related factors for each of the three types of research utilization.Results: The results show that local health officials use epidemiological research more often in a conceptual than an instrumental or symbolic way. This can be explained by the complexity of the local policy process which is often linked to policies in other areas, and the various policy actors involved. Conceptual use was statistically associated with a presentation given by the epidemiologist during the policy process, the presence of obstructions regarding the report's accessibility, and the local official's personal belief systems and interests originating from different professional values and responsibilities. Instrumental and symbolic use increased with the involvement of local officials in the research process.Conclusions: The results of this study provide a partial solution to understanding and influencing research utilization. The quantitative approach underpins earlier qualitative findings on this topic. The outcomes suggest that RPHS epidemiologists can use different strategies to improve research utilization. 'Blurring the boundaries', and the enhancement of interfaces between epidemiologists and local health officials, like direct interactions into each other's work processes, is expected to create better possibilities for optimizing research use