Biochemical Responses in Leaves of 'Sahani' and 'Bidane-Sefid' Grape Cultivars Subjected to Progressing Drought

摘要

The influence of water deprivation on potted grape (Vitis vinifera L.) was investigated. Leaf mass area (LMA) and biochemical responses including chlorophyll, total protein, peroxidase activity, soluble carbohydrates, photosynthesis and stomatal conductance were measured in leaves of 'Sahani' and 'Bidane-Sefid' grape cultivars subjected to progressive drought (soil water potential: -0.2, -0.6, -1 and -1.5 MPa). The results showed a temporary reduction in chlorophyll under drought stress conditions. 'Sahani' had higher chlorophyll compared with 'Bidane-Sefid'. Leaf mass area (LMA) was reduced significantly in 'Bidane-Sefid' under drought. Amount of LMA in 'Sahani' was higher than for 'Bidane-Sefid'. Protein content significantly reduced in -1 and -1.5 MPa treatment in comparison to the control (-0.2 MPa) and -0.6 MPa. Peroxidase activity increased as soil water potential increased. Peroxidase activity increasing of 'Sahani' was higher than for 'Bidane-Sefid'. This study revealed that mild (-0.6 MPa) drought stress affects photosynthesis while moderate (-1 MPa) and severe (-1.5 MPa) drought stress affects chlorophyll, protein, peroxidase activity and soluble carbohydrate levels. These results showed 'Sahani' had higher tolerance to drought condition compared to 'Bidane-Sefid'.