In Central Europe, drought is the most important limiting factor for autumn‐sown cereals. Due to the decline in groundwater, it is a priority to use less water‐demanding forms of crop production. Water use efficiency (WUE) can only be increased if cultivars with satisfactory water management traits are grown, so that they can exploit the water reserves of the soil even if drought occurs during the vegetation. Water consumption and water use efficiency of winter wheat genotypes were investigated in a model experiment carried out in a climate‐controlled glasshouse. The plants were grown either with optimum water supplies or with simulated drought in three phenophases, and measurements were made on the yield parameters, phenological traits and water use parameters of the plants. Substantial differences were observed between the water demands of the cultivars, and it was found that the later the phenophase in which drought was simulated, the greater the decline in water uptake. The analysis of WUE led to the conclusion that the WUE values of cultivars with short vegetation periods dropped to the greatest extent when water deficit was suffered at first node appearance, while cultivars with longer vegetation periods were more sensitive to drought during the heading and grain‐filling stages.

The effects of simulated waterlogging, drought stress and their combination were examined in a model experiment in Martonvásár, Hungary, in 2018. Four modern winter wheat varieties (‘Mv Toborzó’ (TOB), ‘Mv Mambó’ (MAM), ‘Mv Karizma’ (KAR), ‘Mv Pálma’ (PAL)) and one old Hungarian winter wheat cultivar (‘Bánkúti 1201’ (BKT)) were tested. Apart from the control treatment (C), the plants were exposed to two different abiotic stresses. To simulate waterlogging (WL), plants were flooded at four leaf stage, while in the WL + D treatment, they were stressed both by waterlogging and by simulated drought stress at the early stage of plant development and at the heading stage, respectively. The waterlogging treatment resulted in a significant decrease in plant biomass (BKT, TOB), number of spikes (TOB), grain yield (BKT, TOB), water use (BTK) and water-use efficiency (TOB, MAM, PAL) compared to the controls. The combined treatment (WL + D) led to a significant decrease in plant height (BTK, MAM, KAR), number of spikes (BTK, TOB, MAM, KAR), thousand kernel weight (TOB), harvest index (BTK), biomass, grain yield, water-use efficiency (in all varieties) and water use (BKT, TOB, MAM, KAR) of the plants. The best water-use efficiency was observed for MAM; therefore, this genotype could be recommended for cultivation at stress prone areas. The varieties MAM, KAR and PAL also showed good adaptability.

Field crop production must adapt to the challenges generated by the negative consequences of climate change. Yield loss caused by abiotic stresses could be counterbalanced by increasing atmospheric CO₂ concentration, but C₃ plant species and varieties have significantly different reactions to CO₂. To examine the responses of wheat, barley and oat varieties to CO₂ enrichment in combination with simulated drought, a model experiment was conducted under controlled environmental conditions. The plants were grown in climate-controlled greenhouse chambers under ambient and enriched (700 ppm and 1000 ppm) CO₂ concentrations. Water shortage was induced by discontinuing the irrigation at BBCH stages 21 and 55. Positive CO₂ responses were determined in barley, but the CO₂-sink ability was low in oats. Reactions of winter wheat to enriched CO₂ concentration varied greatly in terms of the yield parameters (spike number and grain yield). The water uptake of all wheat cultivars decreased significantly; however at the same time, water-use efficiency improved under 1000 ppm CO₂. Mv Ikva was not susceptible to CO₂ fertilization, while no consequent CO₂ reactions were observed for Mv Nádor and Mv Nemere. Positive CO₂ responses were determined in Mv Kolompos.

Drought and insufficient nutrient supply are the main limiting factors for field crop production; therefore, the present study aimed to investigate the responses of four registered soybean varieties to limited nitrogen (N) supply in combination with drought stress. Plants were grown in tubes filled with silica sand, under open-air conditions. Water shortage was initiated at the three-leaf stage by providing 50% of water, and N deficiency was obtained by reducing the N content of the half-strength Hoagland solution by 50%. N deficiency did not influence the grain yield, while it significantly increased the root dry biomass in Boglár and Pannónia Kincse. Compared with nitrogen supply, the effects of the water shortage were dominant in root development. The expression levels of the investigated genes also showed genotypic variations. The expression of the Inducible nitrate reductase1 gene increased under N-deficient conditions in Boglár and decreased in Pannónia Kincse under drought conditions. The expression level of the aldehyde dehydrogenase gene and abscisic acid 8’-hydroxylase 3 increased under combined stress conditions. Summarising the agronomic and physiological characteristics, Boglár and Sinara were sensitive to drought, Bagera was sensitive to N deficiency but produced the highest yield under limited watering in each nitrogen treatment, while Pannónia Kincse was tolerant to nitrogen deficiency under well-watered conditions.