Water deficit is one of the most important stress factors affecting yield and production quality. Breeders are focusing on breeding wheat cultivars and crop lines that are more resistant to water deficit, so there is a possibility that plants with changes in their ear morphologies, such as long chaff and multi-rowed varieties, will be more resistant to water deficit. Therefore, our research focused on the study of changes in the physiological parameters of wheat cultivar ‘Bohemia’ (normal cob) with an altered morphotype (genotypes ‘284-17’ (long chaff) and genotype ‘29-17’ (multirow cob)), in relation to the duration of the water deficit. The experiment was set up as a container experiment under partially controlled greenhouse conditions. The experimental design included four treatments. The control (C) variant was irrigated regularly. The other treatments were stressed by water deficit, which was induced through the method of gradually drying the substrate: treatment D1 involved 10 days without irrigation, 4 days of watering, 10 days with a re-induced water deficit and 4 days of watering; treatment D2 involved 10 days of watering, and then stress was induced via water deficit until the end of the experiment; treatment D3 involved 10 days of stress and then irrigation until the end of the experiment. The pigment content, gas exchange rate, chlorophyll fluorescence and water potential were monitored in the juvenile wheat plants. The obtained results showed that the contents of photosynthetically active pigments (chlorophyll a and b and carotenoids) were influenced by the gene type. The chlorophyll and carotenoid content were higher in genotype ‘29-17’ (0.080 and 1.925 nM cm⁻², respectively) and lowest in cultivar ‘Bohemia’ (0.080 and 0.080 nM cm⁻², respectively). The chlorophyll content decreased due to water deficit most significantly in the D2 variant (0.071 nM cm⁻²), compared to the control (0.138 nM cm⁻²). The carotenoid content significantly decreased due to water deficiency in the cultivar ‘Bohemia’, D2 (0.061 nM cm⁻²) and the genotype ‘284-17’ (0.075 nM cm⁻²) and non-significantly decreased in ‘29-17’ (1.785 nM cm⁻²). In the control plants, the carotenoid content decreased in the following order: genotype ‘29-17’ (1.853 nM cm⁻²) > genotype ‘284-17’ (0.088 nM cm⁻²) > cv. ‘Bohemia’ (0.087 nM cm⁻²). Wheat plants had a decreased photosynthetic rate due to the closure of stomata and reduction in substomatal CO₂ levels, which were caused by water deficit. The above effect was observed in genotype ‘29-17’ and cultivar ‘Bohemia’. The transpiration rate increased by 0.099 mM m⁻² s⁻¹ (5.69%) in the variety ‘Bohemia’, due to water deficit. On the other hand, the transpiration rate of genotype ‘29-17’ and genotype ‘284-17’ decreased by 0.261 mM m⁻² s⁻¹ (88.19%) and 0.325 mM m⁻² s⁻¹ (81.67%), respectively, compared to the control. Among the genotypes studied, genotype ‘29-17’ showed higher photosynthesis and transpiration rates, compared to genotype ‘284-17’ and the variety ‘Bohemia’. The effect of genotype and water deficit on chlorophyll fluorescence parameters was also shown. In all genotypes studied, there was a significant decrease in water potential due to water deficit, most significantly in the Bohemia variety, then in the genotype ‘284-17’, and the least significant decrease in water potential was seen in the genotype ‘29-17’. Genotype ‘29-17’ appears promising with respect to drought tolerance and photosynthetic rate, despite increased transpiration and reduced water potential; it also appears promising for better water management, with respect to reduced water potential in aboveground organs. On the other hand, the variety Bohemia appears to be less suitable for dry areas, since, despite its relative plasticity, it shows not only high water potential values in the water deficit region but also the most significant decrease in water potential.

Water deficit (drought) is an important environmental factor affecting physiological processes in plants. The present work focuses on the study of changes in physiological responses of juvenile plants (plants in the vegetative phase of growth BBCH 14-16) of selected sorghum genotypes Dokok, 30485, Barnard Red and Ruzrok to water deficit and after rehydration. Water deficit affected the observed physiological parameters-gas exchange and chlorophyll fluorescence. Genotypic differences were also confirmed, with Dokok appearing to be the more sensitive genotype and Ruzrok and Barnard Red appearing to be tolerant. Following rehydration, these parameters increased but did not reach the levels of the control plants. A significant decrease in photosynthetic rate (P n), transpiration (E) and fluorescence compared to the control was found in the water-deficient variant twice for 10 days and 6 days between rehydration periods. Only in the variant where water deficit (14 days) was followed by irrigation (10 days) transpiration increased in genotype 30485. Chlorophyll fluorescence (F v /F m) also decreased significantly in this cultivar. The results suggest that a rehydration period of 14 days is insufficient to restore the photosynthetic functions of stressed sorghum plants.

In addition to its fruit, the sweet cherry (Prunus avium L.) has other parts that can be used as a source of compounds with beneficial biological activity. The content of these metabolites is affected by different inner and outer factors, often as a response to plant defense against various stresses. Leaves of two P. avium. genotypes, Kordia and Regina, grafted on the same rootstock, were analyzed from trees grown in orchards in six different phenological phases for two years. The content of several groups of phenolic compounds, lipid peroxidation, antioxidant activity of the extracts, and enzyme activity were observed via colorimetric methods on a UV/Vis spectrophotometer. The obtained data showed that the content of metabolites and other parameters in these two genotypes are dependent on the term of harvest, as well as environmental conditions, mainly temperature, but sunshine duration and rainfall also had a certain effect on the compounds in the leaves of Kordia and Regina. Even though the differences between these genotypes were not always significant, it is important to consider the right time to harvest the leaves of the sweet cherry, as their content could vary as a result of the reaction to various other conditions and could reflect the resistance of the chosen genotype.

The response of selected physiological parameters to water deficit was investigated in three grapevine cultivars (Vitis vinifera L.): ‘Blue Portugal’, ‘Müller Thurgau’, and ‘Sauvignon Blanc’. The aim of the greenhouse experiment was to evaluate genotype-specific responses to reduced water availability and to assess the effects of water deficit on gas exchange, pigment content, chlorophyll fluorescence, and leaf water potential. Grapevine plants were grown in pots filled with perlite and subjected to five irrigation treatments ranging from 15 to 120 mL per container, applied to create a gradient of water availability. Measurements were performed over a one-month period at regular weekly intervals. Reduced irrigation generally resulted in decreased physiological performance compared to control plants. ‘Müller Thurgau’ showed the strongest reduction in chlorophyll content and gas exchange parameters under low irrigation, indicating high sensitivity to water deficit. In contrast, ‘Blue Portugal’ exhibited relatively stable pigment content under reduced water availability. Differences among cultivars in leaf water potential and gas exchange suggest contrasting water-use strategies. Overall, the results indicate higher drought tolerance in ‘Sauvignon Blanc’, while ‘Müller Thurgau’ appears to be the most sensitive cultivar.

The apple tree (Malus domestica Borkh.) is one of the most economically important fruit crops worldwide, and its productivity is increasingly affected by water deficit. Understanding genotype-specific physiological responses to water deficit is important for improving water deficit resilience in apple. This study evaluated the effects of water deficit (14 days) and subsequent rehydration (7 days) on eight apple genotypes (‘Galaval’, ‘Idared’, ‘Rubinstep’, ‘B11’, ‘HL 308’, ‘HL 2010’, ‘HL 2350’, and ‘HL 827’) grown under semi-controlled container conditions. Physiological parameters, including pigment content, gas exchange, chlorophyll fluorescence, water use efficiency, and leaf water status, were assessed. Water deficit affected all measured parameters, with responses differing among genotypes. In most cases, water deficit was associated with reduced gas exchange and chlorophyll fluorescence, as well as changes in pigment content and leaf water status. However, the magnitude and direction of these responses varied depending on genotype. Some genotypes (e.g., ‘HL 2350’ and ‘B11’) showed more stable physiological performance under water deficit conditions, while others (e.g., ‘Idared’ and ‘Rubinstep’) exhibited more pronounced changes. Rehydration resulted in partial recovery of physiological parameters, although values generally did not reach control levels within the experimental period. The results indicate substantial genotypic variability in physiological responses to short-term water deficit under controlled conditions. These findings provide useful information for further research on water deficit responses in apple; however, additional studies under field conditions and including growth and yield parameters are required to assess the agronomic relevance of the observed differences.

Water deficit (drought) is still one of the most important stress factors affecting not only yields, but also production quality. Breeders are focusing on breeding cultivars and crop lines that are more resistant to water shortages. In addition to breeding, for example, for the size of the roots and changes in the color of the leaves, focus on changing the morphotype i.e. long chaff, multirowed ear. It is predicted that wheat genotypes with a morphotype change should be more drought tolerant. Therefore, our research focused on the study of changes in the physiological parameters of wheat (cv. ´Bohemia´) with a changed morphotype (genotypes ´284-17´ [long chaff] and genotype ´29-17´ [multirowed ear]) in relation to exposure to drought. Pigment content, photosynthesis and transpiration rate, water potential were measured in plants irrigated and affected by water deficit. Water deficit was shown to have a statistically significant effect on transpiration rate, photosynthetic rate, water potential and total chlorophyll content. Furthermore, the influence of the genotype on the observed parameters and on the effect of water deficit was demonstrated. Due to the fact that cv. ´Bohemia´, increases during such periods of transpiration, so for this reason it is not suitable for dry areas. Genotype ́29-17 ́ appears promising with respect to drought resistance.