DROUGHT-INDUCED CHANGES IN CHLOROPHYLL FLUORESCENCE OF YOUNG WHEAT PLANTS

The effects of drought on chlorophyll fluorescence characteristics of photosystem II (PSII) in young winter wheat plants (Triticum aestivum L.) -cv. Sadovo 1 and Katia, were studied. Drought conditions were imposed on 2-week-old plants by withholding water for 10 days. It was found that drought stress increases ground (F-0) fluorescence and decreases maximal (F-m), and variable (F-v) fluorescence, as well as F-v/F-m parameter in dark adapted leaves. In light adapted leaves a significant decrease in quantum yield (Y), photochemical quenching (qP) and electron transport rate (ETR) of PSII was occurred. In conclusion, it is considered that cv. Katia is more tolerant and cv. Sadovo 1 is more sensitive to drought.