Department of Horticulture, Punjab Agricultural University, Ludhiana
The double-sigmoid growth curve was evident in both the cultivars but it was more so in Anab-e-Shahi berries. Total soluble solids were the maximum in Perlette and TSS increased very rapidly at the beginning of stage III in both the cultivars. Titrable acidity was negatively correlated with total soluble solids.
Gibberellin-like activity in berries of both Anab-e-Shahi and Perlette grapes (Vitis vinifera L.) at different stages of development was determined. The gibberellin activity was absent at full bloom in Perlette (April 14) but the maximum activity was recorded on April 21. From May 19 till harvest, no gibberellin activity was found in Perlette berries. Anab-e-Shahi berries also showed the maximum gibberellin activity on April 21, whereas at full bloom, this activity was absent. During stage III, no activity was noted. Anab-e-Shahi berries showed greater gibberellin activity than that of Perlette berries during the berry development. Activity in both Anab-e-Shahi and Perlette berries was mainly in acidic ethyl acetate fraction.
