Growth kinetics of grape berry density (Vitis vinifera L. 'Black Corinth')


  • V. R. Roychev Agricultural University, Plovdiv, Bulgaria
  • G. K. Letchov Agricultural University, Plovdiv, Bulgaria



grape berry density, double sigmoid growth model, seedless vine cultivars, 'Black Corinth', phenology


Density is a significant physical property of grape berries depending on their mass, volume and chemical composition - mass concentrations of sugar, water or other chemical compounds. The current research studies the changes of grape berry density for the seedless grape cultivar 'Black Corinth' from anthesis to maturity. It has been found that the change of grape berry density during the growth follows the double sigmoid curve and consists of two growth cycles divided by a lag phase. During the first growth cycle, between anthesis and lag phase, berry density increases from 800 mg·cm-3 to 1020 mg·cm-3. During the lag phase berry growth is delayed and berry density remains almost a constant. At the end of véraison, berry density rose quickly, and during the technological maturity it reached ~ 1120 mg cm-3. The rate of change of berry density has two local maxima coinciding with the middle of the first and second growth cycles of berry development.

Author Biographies

V. R. Roychev, Agricultural University, Plovdiv, Bulgaria

DSc. Prof. Venelin Roychev

Head of Department of Viticulture

Agricultural University, Plovdiv, Bulgaria


G. K. Letchov, Agricultural University, Plovdiv, Bulgaria

Asst. Prof. George Letchov, PhD 

Department of Mathematics and  Physics

Agricultural University, Plovdiv