Enzymatic activity and physico-chemical changes of terminal bud in rain-fed fig (Ficus carica L. ‘Sabz’) during dormant season

Abstract

Rain-fed fig culture is known to provide a good quality of dried figs, while almost no research has been reported so far on the enzyme activity comparisons of seasonal variations among terminal buds in this plant. Toward this goal, we evaluated the physiochemical changes of terminal buds of fig 'Sabz' and their micromorphology during the dormant season (November to April) using Scanning Electron Microscope (SEM) analysis during two consecutive years (2016 and 2017). Results indicated that the highest contents of total sugars in terminal fig buds were registered in January and the lowest values were noticed in April. SEM analysis showed the presence of vegetative terminal fig buds during the dormant season and after bud-break in April. An increasing trend was observed for the protein content, length and diameter of terminal buds at the beginning of bud-break. In dormant buds, ascorbate peroxidase, peroxidase and catalase enzymes exhibited initially an ascending pattern, while it decreased from December. A second increase for these enzymes occurred during the dormant season until bud-break. Superoxide dismutase activity increased in buds during the dormancy season until bud-break. Proline content remained stable in buds from November to February, while it decreased rapidly until bud-break. Furthermore, a downward trend of the total phenol content in buds was observed between the onset and end of dormant period. In general, the dormant buds in ʻSabzʼ fig cultivar were metabolically active with a short dormant period under the rain-fed conditions.

Keywords

• Fig
• Dormancy
• Bud break
• Enzyme activity
• Micromorphology