Page 53 - Grapevine SeptOct 2021

Around The Vineyard

aims to expand it to other grape diseases like pow- fruit once it comes in, making split picking less rele-
dery mildew. vant. However, I would also argue that it has poten-
tial in many wine-growing regions of the US where
Precision Irrigation: Vinay Pagay and Bruno grading practices are not standardized. I could see
Tisseyre both discussed exciting research on preci- it playing a role in Minnesota, where I am based.
sion irrigation. That is, mapping vine water status
across the vineyard to apply irrigation by zones UV light for disease control: Dr. David Gadoury,
rather than applying the same amount of water plant pathologist at Cornell University, has worked
everywhere. Pagay’s group is researching the use of extensively to develop a method to control patho-
crop water status index and drone-mounted NDVI gens with UV light exposure during the night.
sensors for this purpose. Thanks to ongoing research efforts, this practice
has come a long way over the last 30 years or so.
Estimating Yield: Mason Earles and Jaco Fourie
both spoke about ongoing research on image- Currently, Gadoury’s team is finding excellent
based yield estimation. They are deploying sensors suppression of powdery mildew and mites using
through the vineyard to capture images of clusters, nighttime UV exposure. They have also had good
to estimate fruit density throughout the vineyard suppression of sour rot based on one year of data.
and create yield estimation maps. Their data also suggests that UV treatment can sup-
press downy mildew in a mild year but not a severe
If the researchers are able to train the sensors to year.
accurately recognize clusters and cluster size, this
could enable more efficient yield estimation for They have found no evidence of harmful effects
larger vineyards where yield estimation by human of nighttime UV application on the vine, and have
crews is too time consuming. found that it is effective across multiple specialty
crops. Read more about this project here.
Split Picking: Bramley described one intriguing
use of PV, for “split picking.” That is, pricing fruit My personal take-home message was that UV
based on quality in particular areas of the vineyard. technology is very promising, and equipment man-
By mapping differences in fruit quality, anthocy- ufacturers will need to get on board in order for it
anins, malic acid, and YAN across the vineyard, to be widely adopted.
growers could identify their highest quality blocks
and sell that fruit at premium prices. This is not cur- Where are we on
rently a common practice. Adopting Precision Viticulture?

Bramley argued that California wineries grade the Are you feeling intrigued but don’t know where to

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