Change in plant growth and some bioactive components of the tomato under water deficit with exogenous chrysin treatment

Drought is one of the important factors that cause a decrease in productivity and quality in plant cultivation. Stress tolerance in plants can be increased or damage can be reduced by various exogenous applications. One of them is flavonoids, which have an important role in the response to stress through changes that occur at the endogenous level in the plant due to drought stress. The effects of exogenous treatment of chrysin, a member of the flavonoid group, on tomato seedlings grown under water deficit were examined. Different doses (C0: Control with no treatment, C1: 0.1 mM, C2: 0.5 mM and C3: 1.0 mM) of chrysin solutions were applied to the leaves under full irrigation (100% field capacity (FC)) and water deficit (60% of FC). The effects of the treatments were investigated in terms of many biochemicals, physiological and morphological properties, as well as their bioactive components. As a result, it was determined that the adverse effects of drought stress on plant were alleviated by chrysin, and better results were obtained, especially with applications at 0.5 and 1.0 mM doses. With drought, PFW, PDW, RFW, RDW, PH, SD, LA and LRWC decreased by 35%, 56%, 23%, 20%, 25%, 12%, 24% and 10%, respectively, but these reductions under drought with chrysin treatments were lower. While ABA content increased with water stress, treatments suppressed this increase. The effect of these applications is also thought to occur through plant antioxidant activity, phenolic compounds and osmoprotectants such as amino acids, sugar and organic acids. With the changes in bioactive components with chrysin treatment, the rate of damage from stress decreased. This study is one of the first chrysin applications to tomato, it would be useful to detail the research at the molecular study to understand the effectiveness of the treatment in all aspects.