Characteristics of Yield Parameters and Anthocyanin Accumulation under Water Deficit Stress.

Plants exposed to drought stress conditions often increase the synthesis of anthocyanins-natural plant pigments and antioxidants. However, water deficit (WD) often causes significant yield loss. The aim of our study was to evaluate the productivity as well as the anthocyanin content and composition of berries from cultivated "Rojan" and hybrid No. 17 plants (seedlings) grown under WD. The plants were grown in an unheated greenhouse and fully irrigated (control) or irrigated at 50% and 25%. The number of berries per plant and the berry weight were evaluated every 4 days. The anthocyanin content and composition of berries were evaluated with the same periodicity using HPLC. The effect of WD on the yield parameters of two evaluated genotypes differed depending on the harvest time. The cumulative yield of plants under WD was not less than that of the control plants for 20-24 days after the start of the experiment. Additionally, berries accumulated 36-56% (1.5-2.3 times, depending on the harvest time) more anthocyanins compared with fully irrigated plants. Our data show that slight or moderate WD at a stable air temperature of about 20 °C positively affected the biosynthesis of anthocyanins and the yield of berries.