Drought is characterised as a recurring climatic phenomenon with prolonged duration, affecting land through below-average rainfall and often accompanied by high temperatures. When the available water falls below the optimum level, water deficit or water stress arises, disrupting normal plant processes. This condition poses challenges for plant growth and development as it hampers the internal water transport, induces stomatal closure, and limits access to photosynthetic resources.
The study employed the annual sunflower as the experimental plant. The plants were cultivated in a controlled environment with a temperature ranging from 20 to 25°C and a humidity level of 55 to 60%, supplemented by MARS HYDRO artificial LED lighting set to a 12-h photoperiod. Radial changes in the plant stems were monitored using a DD-S type dendrometric sensor to measure radial fluctuations. The collected data were recorded in a dendrometric data logger DL 18. Data collection occurred at hourly intervals from February 20 to March 9, 2023. The nine plants were divided into three groups, each comprising three plants. All plants from groups 1 and 2 received irrigation at one- day intervals (group 1 – 80 cm ³ per plant, group 2 – 40 cm ³ per plant) and group 3 was not irrigated.
Based on these findings, visible water stress was evident in the plants under experimental conditions. Consequently, continuous monitoring throughout the growing season will be essential to adjust the irrigation rate to meet the requirements of the plants.

In the present research, a scripting cartographic technique for the environmental mapping of Ethiopia using climate and topographic datasets is developed. The strength of the Generic Mapping Tools (GMT) is employed for the effective visualisation of the seven maps using high-resolution data: GEBCO, TerraClimate, WorldClim, CRUTS 4.0 in 2018 by considering the solutions of map design. The role of topographic characteristics for climate variables (evapotranspiration, downward surface shortwave radiation, vapour pressure, vapour pressure deficit and climatic water deficit) is explained. Topographic variability of Ethiopia is illustrated for geographically dispersed and contrasting environmental setting in its various regions: Afar, Danakil Depression, Ethiopian Highlands, Great Rift Valley, lowlands and Ogaden Desert. The relationships between the environmental and topographic variables are investigated with aid of literature review and the outcomes are discussed. The maps are demonstrated graphically to highlight variables enabling to find correlations between the geographic phenomena, their distribution and intensity. The presented maps honor the environmental and topographic data sets within the resolution of the data. Integration of these results in the interpretation maps presented here brings new insights into both the variations of selected climate variables, and the topography of Ethiopia.

Drought significantly impacts the growth and yield of forage grasses, particularly its effect on Dactylis glomerata photosynthetic apparatus during the initial phase of development remains largely unknown. This study investigated the effects of drought on physiological parameters of various D. glomerata varieties. The seedlings obtained after seed germination under optimal and simulated drought conditions by PEG 6000 (three variants) were planted in small pots filled with garden substrate. Over a span of 42 days, the plants were initially kept well-watered (70% capillary water capacity, CWC), after which half of the seedlings from each variant were subjected to drought. This drought stress was applied during the tillering phase for 12 days. Subsequently, the plants were rehydrated (at 70% CWC) and allowed to recover for 14 days. Throughout both drought and recovery periods, measurements were taken. Leaf chlorophyll fluorescence parameters were assessed, and the JIP-test analysis was utilised to provide detailed insights into the functionality of D. glomerata photosynthetic apparatus under drought stress and post-recovery conditions. Several parameters were identified as indicative of the plants’ sensitivity to drought, such as performance indices PI _ABS and PI _tot, along with quantum yield parameters Ψ _E0, φ _E0, and φ _P0. The results highlighted that var. Minora and Tukan exhibited greater tolerance to water deficit when compared to the other varieties studied. They showed a large increases in PIABS and PItot values after drought stress as well as after the re-watering (recovery period) compared to control plants. This suggests their potential for better adaptation to drought conditions.