Assessing winter bud injury on grapevine - What's happening in the field?

What's happening in the field?

At the Missouri State Fruit Experiment Station

Assessing winter bud injury on grapevine

by

Since we have experienced winter lows of minus 8 and minus 6 degrees Fahrenheit in January, we assessed winter bud injury for some cultivars. As part of his VESTA practicum work, Jeremy Emery is managing the assessment. Jeremy, Randy Stout and Asher Ramsey have all learned the assessment process and evaluated the % primary bud mortality for the following cultivars.

 

Cultivar % primary bud mortality*
Cayuga White 12%
Chambourcin 50%
Norton 0%
Seyval Blanc 9%
Vidal Blanc 5%

 

* Based on number of dead primary buds in a 100 bud representative sample.

Jeremy slices through buds on the collected grape canes to assess cold injury.
Jeremy slices through buds on the collected grape canes to assess cold injury.
Starting at the tip, you take slices parallel to the base off until you to get to the primary bud.
Starting at the tip, you take slices parallel to the base off until you to get to the primary bud.
A live primary shows bright green concentric rings in the middle of the compound bud.
A live primary shows bright green concentric rings in the middle of the compound bud.
Asher, Jeremy and Randy have evaluated the winter injury of the grape cultivars before pruning so we can increase the number of buds left if needed.
Asher, Jeremy and Randy have evaluated the winter injury of the grape cultivars before pruning so we can increase the number of buds left if needed.