Araus J.L., Caims J.E. (2014): Field high-throughput phenotyping: the new crop breeding frontier. Journal of Trends in Plant Science, 19: 52–61. https://doi.org/10.1016/j.tplants.2013.09.008 Ayeneh A., van Ginkel M., Reynolds M.P., Ammar K. (2002): Comparison of leaf, spike, peduncle and canopy temperature depression in wheat under heat stress. Field Crops Research, 79: 173–184. https://doi.org/10.1016/S0378-4290(02)00138-7 Botyanszka L. (2019): Development of phenotyping methods and diagnostic approaches useful in identification of the tolerant crop genetic resources. [Dissertation Thesis] Nitra, Slovak University of Agriculture. Brestic M., Zivcak M. (2013): PSII fluorescence techniques for measurement of drought and high temperature stress signal in crop plants: protocols and applications. In: Rout G.R., Das A.B. (eds.): Molecular Stress Physiology of Plants. Dordrecht, Springer, 87–131. ISBN: 9788132208075 Brestic M., Živcak M., Hauptvogel P., Misheva S., Kocheva K., Yang X., Li X., Allakhverdiev S.I. (2018): Wheat plant selection for high yields entailed improvement of leaf anatomical and biochemical traits including tolerance to non-optimal temperature conditions. Photosynthesis Research, 136: 245–255. https://doi.org/10.1007/s11120-018-0486-z Chaves M.M., Flexas J., Pinheiro C. (2008): Photosynthesis under drought and salt stress: regulation mechanisms from whole plant to cell. Annals of Botany, 103: 551–560. https://doi.org/10.1093/aob/mcn125 Chen Y.E., Su Y.Q., Zhang C.M., Ma J., Mao H.T., Yang Z.H., Yuan M., Zhang Z.W., Yuan S., Zhang H.Y. (2017): Comparison of photosynthetic characteristics and antioxidant systems in different wheat strains. Journal of Plant Growth Regulation, 37: 347–359. https://doi.org/10.1007/s00344-017-9731-5 Chovancek E., Zivcak M., Botyanszka L., Hauptvogel P., Yang X., Misheva S., Hussain S., Brestic M. (2019): Transient heat waves may affect the photosynthetic capacity of susceptible wheat genotypes due to insufficient photosystem I photoprotection. Plants, 8: 282. https://doi.org/10.3390/plants8080282 Farooq M., Hussain M., Siddique K.H. (2014): Drought stress in wheat during flowering and grain-filling periods. Critical Reviews in Plant Sciences, 33: 331–349. https://doi.org/10.1080/07352689.2014.875291 Ferroni L., Živčak M., Sytar O., Kovár M., Watanabe N., Pancaldi S., Brestič M. (2020): Chlorophyll-depleted wheat mutants are disturbed in photosynthetic electron flow regulation but can retain an acclimation ability to a fluctuating light regime. Environmental and Experimental Botany, 178: 104156. https://doi.org/10.1016/j.envexpbot.2020.104156 Goltsev V., Zaharieva I., Chernev P., Kouzmanova M., Kalaji H.M., Yordanov I., Krasteva V., Alexandrov V., Stefanov D., Allakhverdiev S.I., Strasser R.J. (2012): Drought-induced modifications of photosynthetic electron transport in intact leaves: analysis and use of neural networks as a tool for a rapid non-invasive estimation. Biochimica et Biophysica Acta (BBA) – Bioenergetics, 1817: 1490–1498. https://doi.org/10.1016/j.bbabio.2012.04.018 Hussain S., Ulhassan Z., Brestic M., Zivcak M., Zhou W., Allakhverdiev S.I., Yang X., Safdar M.E., Yang W., Liu W. (2021): Photosynthesis research under climate change. Photosynth Research, 150: 5–19. https://doi.org/10.1007/s11120-021-00861-z Jedmowski C., Bayramov S., Brügemann W. (2014): Comparative analysis of drought stress effects on photosynthesis of Eurasian and North African genotypes of wild barley. Photosynthetica, 52: 564–573. https://doi.org/10.1007/s11099-014-0064-3 Kaiser W.M. (1987): Effect of water deficit on photosynthetic capacity. Physiologia Plantarum, 71: 142–149. https://doi.org/10.1111/j.1399-3054.1987.tb04631.x Kalaji H.M., Oukarroum A., Alexandrov V., Kouzmanova M., Brestic M., Zivcak M., Samborska I.A., Cetner M.D., Allakhverdiev S.I., Goltsev V. (2014): Identification of nutrient deficiency in maize and tomato plants by in vivo chlorophyll a fluorescence measurements. Journal of Plant Physiology and Biochemistry, 81: 16–25. https://doi.org/10.1016/j.plaphy.2014.03.029 Kalaji H.M., Schansker G., Brestic M., Bussotti F., Calatayud A., Ferroni L., Goltsev V., Guidi L., Jajoo A., Li P., Losciale P., Mishra V.K., Misra A.N., Nebauer S.G., Pancaldi S., Penella C., Pollastrini M., Suresh K., Tambussi E., Yanniccari M., Zivcak M., Cetner M.D., Rusinowski I.A., Baba W. (2017): Frequently asked questions about chlorophyll fluorescence, the sequel. Photosynthesis Research, 132: 13–66. https://doi.org/10.1007/s11120-016-0318-y Long S.P., Colon A.M., Zhu X.G. (2015): Meeting the global food demand of the future by engineering crop photosynthesis and yield potential. Journal of Cell, 161: 56–66. https://doi.org/10.1016/j.cell.2015.03.019 Lu C., Zhang J. (1999): Effect of water stress on photosystem II photochemistry and its thermostability in wheat plants. Journal of Experimental Botany, 336: 1199–1206. https://doi.org/10.1093/jxb/50.336.1199 Massaci A., Battistelli A., Loreto F. (1996): Effect of drought stress on photosynthetic characteristics, growth and sugar accumulation of field-grown sweet sorghum. Journal of Functional Plant Biology, 23: 331–340. https://doi.org/10.1071/PP9960331 Monneveux P., Jing R., Misra S.C. (2012): Phenotyping for drought adaptation in wheat using physiological traits. Frontiers in Physiology, 3: 429. https://doi.org/10.3389/fphys.2012.00429 Psidova E., Zivcak M., Stojnić S., Orlović S., Gőmőry D., Kucerova J., Ditmarova L., Střelcova K., Brestic M., Kalaji H.M. (2018): Altitude of origin influences the responses of PSII photochemistry to heat waves in European beech (Fagus sylvatica L.). Journal of Environmental and Experimental Botany, 152: 97–106. https://doi.org/10.1016/j.envexpbot.2017.12.001 Sharkey T.D. (2005): Effects of moderate heat stress on photosyntesis: importance of thylakoid reactions, rubisco deactivation, reactive oxygen species, and thermotolerance provided by isoprene. Journal of Plant, Cell and Environment, 28: 269–277. https://doi.org/10.1111/j.1365-3040.2005.01324.x Sharma D.K., Andersen S.B., Ottosen C.-O., Rosenqvist E. (2012): Phenotyping of wheat cultivars for heat tolerance using chlorophyll a fluorescence. Journal of Functional Plant Biology, 39: 936–947. https://doi.org/10.1071/FP12100 Srivastava A., Guissé B., Greppin H., Strasser R.J. (1997): Regulation of antenna structure and electron transport in photosystem II of Pisum sativum under elevated temperature probed by the fast polyphasic chlorophyll a fluorescence transient: OKJIP. Biochimica et Biophysica Acta (BBA) – Bioenergetics, 1320: 95–106. https://doi.org/10.1016/S0005-2728(97)00017-0 Stirbet A., Lazár D., Kromdijk J., Govindjee G. (2018): Chlorophyll a fluorescence induction: can just a one-second measurement be used to quantify abiotic stress responses? Journal of Photosynthetica, 56: 86–104.  https://doi.org/10.1007/s11099-018-0770-3 Stirbet S.A., Govindjee G. (2011): On the relation between the Kautsky effect (chlorophyll a fluorescence induction) and photosystem II: basics and applications of the OJIP fluorescence transient. Journal of Photochemistry and Photobiology B: Biology, 104: 236–257. https://doi.org/10.1016/j.jphotobiol.2010.12.010 Strasser R.J., Srivastava A., Tsimilli-Michael M. (2000): The fluorescence transient as a tool to characterise and screen photosyntetic samples. Probing Photosynthesis Mechanisms, Regulation and Adaption, 25: 445–483. Tuberosa R. (2012): Phenotyping for drought tolerance of crops in the genomics era. Frontiers in Physiology, 3: 347. https://doi.org/10.3389/fphys.2012.00347 Wang W., Vinocur B., Altman A. (2003): Plant responses to drought, salinity and extreme temperatures: towards genetic engineering for stress tolerance. Planta, 218: 1–14. https://doi.org/10.1007/s00425-003-1105-5 Yang X., Chen X., Ge Q., Li B., Tong Y., Li Z., Kuang T., Lu C. (2007): Characterisation of photosynthesis of flag leaf in a wheat hybrid and its parents grown under field conditions. Journal of Plant Physiology, 164: 318–326. https://doi.org/10.1016/j.jplph.2006.01.007 Yeh Ch.-H., Kaplinsky N.J., Hu C., Charng Y.-Y. (2012): Some like it hot, some like it warm: phenotyping to explore thermotolerance diversity. Journal of Plant Science, 195: 10–13. https://doi.org/10.1016/j.plantsci.2012.06.004 Zivcak M., Olsovksa K., Brestic M. (2017): Photosynthetic responses under harmful and changing environment: practical aspects in crop research. In: Hou H.J.M. (ed.): Photosynthesis: Structures, Mechanisms, and Applications. Dordrecht, Springer, 203–248. ISBN-13: 978-3319488714 Zivcak M. (2013): Photosynthetic electron transport and specific photoprotective responses in wheat leaves under drought stress. Photosynthesis Research, 117: 529–546. https://doi.org/10.1007/s11120-013-9885-3 Zivcak M., Brestic M., Olsovska K., Slamka P. (2008): Performance index as a sensitive indicator of water stress in Triticum aestivum L. Plant, Soil and Environment, 54: 133–139. https://doi.org/10.17221/392-PSE Zivcak M., Brestic M., Botyanszka L., Chen Y.-E., Allakhverdiev S.I. (2019): Phenotyping of isogenic chlorophyll-less bread and durum wheat mutant lines in relation to photoprotection and photosynthetic capacity. Photosynthesis Research, 139: 239–251. https://doi.org/10.1007/s11120-018-0559-z