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- Multifaceted impact of exogenous salicylic acid on vicia faba l. under salt stress: plant growth, water status, and photosynthetic performance (OJIP Fluorescence)Publication . ANAYA, FATIMA; Fghire, R.; Wahbi, S.; Carvalho, Inês; Loutfi, K.Purpose This study investigated the effect of salt stress on growth, water status, and photosynthetic activity in faba bean plants and the role of salicylic acid (SA) in mitigating the harmful effects of salt stress. Methods Faba bean plants were subjected to different levels of salt stress (0, 90, 120, and 150 mM NaCl) and salicylic acid (0, 0.5, and 1 mM SA). Salt and SA treatments were applied starting from the seedling stage and continued for two months. Results Results show that salt stress significantly affects the different studied parameters. Salinity strongly decreases the plant weight (fresh and dry) and the plant water status (Leaf Water Potential (LWP), Stomatal conductance (gs), Relative water content (RWC). The analysis of the Photosystem II (PSII) function disruption indicates that salt stress induced an electron transport inhibition at the donor side of the PSII due to the Oxygen-Evolving Complex (OEC) inactivation (positive- K-band) and reduced the PSII unit’s energetic connectivity (positive-L-band). The evaluation of the rate reduction of the end electron acceptor at the Photosystem I (PSI) side revealed that salt stress resulted in gradual decreases in the reduction rates. Nevertheless, the exogenous application of salicylic acid (SA) allowed plants to maintain a high weight/length value with a significant improvement in plant water status. Chlorophyll-a fluorescence analysis shows that SA application improved at the donor side of electron transport (lower intensity of the K and L-band), with a larger pool size under the combination of 0.5 mM SA and high salt stress levels applications. Conclusion These results suggest that the salt stress significantly affects the PSII by the inactivation of the OEC and decreas¬ing the PSII unit’s connectivity. However, SA had a beneficial effect on the PSII and PSI salt stress tolerance in Vicia faba L.
- Baboon route repetition in a seasonal environmentPublication . Lewis-Bevan, Lynn Catrin; Hammond, Philippa; Carvalho, Susana; Biro, DoraIntroduction: Route-based navigation is a common movement strategy for a variety of taxa, wherein animals repeatedly re-use familiar paths during travel. However, this type of navigation is understudied in wild animals that experience regular displacement, raising questions about the robustness and longevity of such routes and route memories. The seasonal flooding of Gorongosa National Park, Mozambique, provides an opportunity to test multiple facets of route-based navigation in wild primates, due to its high seasonality and annual flooding.Methods: Data was collected from GPS collars placed on four chacma baboons in two troops in Gorongosa National Park. Using GPS points taken every 15 minutes, we use nearest-neighbour analysis to compare daily paths across the year, to identify high-use paths. We then look at the identified high-use paths to see if they are used across the entire study period, with a focus on areas that were vacated for more than two months of the study period.Results: We find that the baboons do have vacated areas, but return to the same areas after displacement. We did not find high-use routes in these areas used both before and after displacement, although high-use routes did exist that were used across the study period in different areas.Discussion: Our results indicate that routes may not be maintained in long-term memory spanning several months, or that route reuse is in part dependant on seasonal resources or navigational aids. Although the study period did not span a full year, this study presents a replicable method of analysing route reuse and identifying high-use routes without traditional methods of manually overlaying and analysing daily paths.