Bud-break through Early Shoot Growth

The bud in the image at left has emerged from its protective budscales and its leaves have not yet expanded. Note the large amount of light colored trichomes covering its surfaces. Many varieties of Vitis have trichomes on their mature leaves as well. It appears, however, that the most newly developed leaves have a thicker covering of these trichomes. Perhaps these serve as protection against overexposure to bright light or as a deterrent to insect pests.
One leaf stage on Merlot.
Two leaves have now expanded out from the closed bud. This is termed the two-leaf stage.
Two leaf stage on Merlot.
This photo depicts the apical end of a shoot in early shoot growth. Note the drops of clear fluid on the different areas of this shoot. These are termed pearl glands or "sap balls".
Early shoot growth on Merlot.

A close up view of pearl glands.


Pearl glands on Merlot.

Dormancy through Bud-swell

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