Genes from the DREB family are involved in plant's responses to dehydration and possibly play a role in their ability to tolerate water stress. Understanding the relationship between water stress tolerance and expression of specific genes requires the isolation and characterisation of the sequences that may be involved. We report the isolation and characterisation of a gene in Triticum durum, namely TdDRF1, which belongs to the DREB gene family and produces three forms of transcripts through alternative splicing. The relationship between the expression profile of the TdDRF1 gene and water stress was assessed by real-time reverse transcription-polymerase chain reaction in a time-course experiment up to 7 days. Water stress experimental conditions were selected to relate changes in gene expressions during a time frame reflecting as closely as possible those during which water stress starts having a visible effect under field conditions. Among the three isoforms of TdDRF1, the truncated form TdDRF1.2 was at all times the most expressed. Its expression, together with the TdDRF1.3 transcript, increased sharply after 4 days of dehydration, but then decreased at 7 days. The TdDRF1.1 transcript was the least expressed overall and varied least with the duration of dehydration. Genotypic differences in TdDRF1 gene expression are currently under investigation.

This study describes the conservation status of dune systems in relation to disturbance factors in the coastal stretch of the Viterbo province, Latium Region, Italy. Particular emphasis was given to the bioindication value of plant communities and their sequence. Each plant community was considered as a "habitat" in accordance with Annex I of the Directive 92/43/EU. Stress factors, such as sand dynamic and erosion, and anthropogenic pressures, such as trampling and bathing settlements, influence the sequence of habitats and weaken the system of relations that makes these coenoses to occur in extreme conditions. The choice to carry out surveys along wide transects, recording different data, allowed to explore the use of habitats as bioindicators. Comparing sites characterized by the same extension in a homogeneous area, it was possible to expand the use of canonical correspondence analysis (CCA) as a tool to correlate habitat composition and disturbance factors. The application of CCA showed a high correlation of degradation and habitat loss with coastal erosion, trampling and presence of waste. Furthermore, floristic surveys allowed the application of different biodiversity indices to quantify species richness of sampled areas. The conservation status of the sites investigated was found to be diverse, from the total disappearance of the mobile dune habitats to their complete sequence. The proposed methodology has been useful to fulfill the objective of the work and is applicable to other case studies in the Mediterranean.

No abstract

Olive is of major eco-social importance for the Mediterranean Basin, a climate change and biodiversity hotspot of global relevance where remarkable climate change is expected over the next few decades with unknown ecosystem impacts. However, climate impact assessments on terrestrial ecosystems have long been constrained by a narrow methodological basis (ecological niche models, ENMs) that is correlative and hence largely omits key impact drivers such as trophic interactions and the effect of water availability, the latter being especially relevant to desertificationprone Mediterranean ecosystems. ENMs use correlative measures of water availability unsuitable for making projections about the future. To bridge this gap, mechanistic approaches such as physiologically-based weatherdriven demographic models (PBDMs) may be used as they embed by design both the biology of trophic interactions and a mechanistic representation of soil water balance. Here we report progress towards assessing climate effects on olive culture across the Mediterranean region using mechanistic PBDMs that project regionally the multitrophic population dynamics of olive and olive fly as affected by daily weather and soil water balance.

No abstract