Akademik Veri Yönetim Sistemi
MITTEILUNGEN KLOSTERNEUBURG, cilt.68, sa.2, ss.67-81, 2018 (SCI-Expanded)
This study was conducted to evaluate the correlations between the low-temperature tolerance level of buds and biochemical parameters such as malondialdehyde (MDA) as a lipid peroxidation marker, total soluble carbohydrate content, total soluble protein content, peroxidase (POD), superoxide radical (O-2(center dot-)) and hydrogen peroxide (H2O2) in buds of Vitis vinifera cv. 'Karaerik'. For the experiments, the dormant grape buds in the cold acclimation (CA), hardening (HA) and deacclimation (DA) stages were used. The tolerance levels of buds were determined by measuring low-temperature exotherms (LTEs) obtained from thermal analysis (TA). It is the first report, that mLTE is related to mHTE (mean temperature at which high-temperature exotherms occurred). The mLTE is the temperature at which intracellular ice formation occurred. Intracellular ice formation is lethal. The mHTE is the temperature at which extracellular ice formation occurred. Extracellular ice formation is non-lethal. mHTE was statistically correlated (r = 0.676) with mLTE. Also, the relationships between the mLTE and total soluble protein (r = -0.433), total soluble carbohydrate (r = -0.486), O-2(center dot-) (r = -0.515), H2O2 (r = -0.360), peroxidases (POD) (r = 0.586) and MDA (r -0.490) were statistically significant. In conclusion, we suggest that O-2(center dot-), H2O2, and MDA can be used as indicator for low-temperature stress of grapevine, but although there was a correlation between POD activity and the mLTE value of dormant bud, it has been hypothesised that POD did not affect cold-tolerance of 'Karaerik' grapevines. Furthermore, it can be accepted as the first report with respect to the fact that decreasing extracellular freezing temperatures decrease the temperature of intracellular ice formation.