The following are some
notes for you to consider if you are seeing these pests appear in your
vineyards. Before choosing to apply any pest
control product, be sure to check the most recent version of the label either
provided by your supplier or available from https://pr-rp.hc-sc.gc.ca/ls-re/index-eng.php
INSECT PESTS
Japanese Beetle populations are continuing to appear and
are climbing at a slow and steady pace. Monitor closely as these beetles can be around for another 4-5 weeks. Thresholds are very high for these foliar feeding beetles and are listed at 25-30% leaf injury or 25 beetles per meter on full canopies of
mature vines. Altacor has a suppression effect on Japanese Beetle as long as the entire canopy is sprayed. Later in the season, if control is required, Assail/Aceta is registered against Japanese Beetle. Be
aware that Imidan is no longer an option in grapes this season as all uses on grapes have been cancelled as of October 30, 2022.
Leafhopper activity has been low.
Multiple species of leafhoppers can attack grapes. The potato leafhopper feeding injury is characterized by marginal chlorosis (yellowing around the leaf perimeter) and the leaf edges will start to roll downward.
Registered pyrethroid products on grapes include Pounce, Perm-up, Ship or Up- Cyde. Assail/Aceta is also available for leafhopper control.
For organic growers products that contain pyrethrum may be effective but only
last for a few days.
At most vineyards that have been using sulphur in their recent fungicide applications, Erineum Mite (EM) levels are stable. In vineyards where continued activity is being observed, keep applying sulphur material even though you are using systemic materials for mildew control. For hybrid growers,
oils (1% v/v concentration) are effective in suppressing erineum mite
populations to a similar level as lower rates (3-4 kg/ha) of sulphur does. Oils
also appear to have suppressing effects on phylloxera and early leafhoppers.
If hybrid blocks are continuing to see new Phylloxera galls developing on leaves in the upper canopy, you should consider an application of Assail/Aceta or Clutch. Movento is another option however, we have found that post-bloom applications of Movento are not as effective against phylloxera as pre-bloom applications since the life cycles of phylloxera become scattered at this stage of the season. Remember that Movento will only have effect on phylloxera that are actively feeding. Assail/Aceta and Clutch are contact sprays that are focused on the crawler stage of development. To get full control of the recent flush of phylloxera, two applications of Assail/ Aceta or Clutch are recommended 7-10 days apart. This will subject the phylloxera population to a longer period of residual control and should provide reliable
results on eggs that hatch over a two to three-week period. This will also control any leafhoppers that may be present.
DISEASE MANAGEMENT
Phomopsis: Labrusca and hybrid cultivars are most susceptible to problems with Phomopsis cane and leaf spot. Products effective against Phomopsis
include Manzate, Captan/Maestro, Folpan/Follow, Diplomat and Allegro. Be aware of the restrictions around Captan/Maestro as the REI is now 55-days for hand labour. Also, effective for the 2023 growing season, mancozeb (Manzate/Dithane) applications are restricted to a single application in grapes at 2.25 kg a.i. per ha (or 3 kg of a 75% a.i. formulation) with a 7-day REI for hand leaf removal, training and crop thinning and a 66-day PHI.
For organic vineyards, copper products or a peroxide product such as Oxidate 2.0 will suppress Phomopsis, but they are not rated as strong against this disease. A soft chemistry product like Diplomat can provide some additional protection against phomopsis, however this product is not certified organic and should not be used by certified organic growers. As always, check with your organic certification body to determine what products are acceptable for use before applying anything to the crop. See below for efficacy ratings and product restrictions pertaining to these protectant products used
for Phomopsis.
Fungicides registered for the 2023
season that have activity on Phomopsis in grapes.
|
Product (Group) |
Application Rate @ 3-Leaves |
Re-Entry Interval |
Activity Rating on Phomopsis |
|
Manzate (M) |
2-3 kg/ha |
24 h |
3/3 |
|
Maestro/Captan WSP (M) |
2 kg/ha |
12 h (general) 55 d (hand labour) |
3/3 |
|
Folpan/Follow (M) |
1.25 kg/ha |
24 h |
3/3 |
|
Allegro (29) |
1 L/ha |
24 h |
3/3 |
|
Diplomat (19) |
926 mL/ha |
12 h |
2/3 |
|
LifeGard (P6) |
250-333 g/ha |
4 h |
3/3 |
|
Copper products (M) |
See labels (product dependent) |
4 h - 48 h (product dependent) |
1/3 |
|
Oxidate 2.0 (NC) |
1% v/v |
4 h (or when dry) |
1/3 |
Group M materials are commonly used since they are relatively inexpensive and are not prone to resistance, so they can be used in back-to-back applications. The major disadvantages of these materials are that they are at risk of washing off. Reapplication of these products are required every 7-8 days or if we experience more than 15 mm of rain. Do not cut rates on systemic or locally systemic materials at any time as this can lead to significantly reduced efficacy and is a very quick way to develop resistance!
Black Rot: Manzate is restricted to an
individual use per season to control Black Rot and
has a 66-day preharvest interval. For organic growers, LifeGard and Stargus are rated as having good efficacy against black rot but are protective not curative if extensive
infections are observed. Oxidate 2.0, copper products, Diplomat, Folpan/Follow and Captan/Maestro only provide a suppression effect against black rot.
Table 2. Pre-bloom fungicides registered
for the 2023 season in vineyards that have activity on downy mildew and black
rot on grapes.
|
Product
(Group) |
Application Rate |
Re-Entry
Interval |
Activity on Black
Rot |
|
Manzate (M) only one application per
season |
3 kg/ha (output) |
24 h |
3/3 |
|
Maestro/Captan
WSP (M) |
2.5 kg/ha
(output) |
12 h (general) 55 d (hand labour) |
1/3 |
|
Folpan/Follow (M) |
1.25 kg/ha |
24 h |
1/3 |
|
Allegro (29) |
1 L/ha |
24 h |
0/3 |
|
Diplomat (19) |
926 mL/ha |
12 h |
1/3 |
|
LifeGard (P6) |
250-333 g/ha |
4 h |
3/3 |
|
Stargus (BM2) |
3.0-4.0 L/ha |
4 h |
2/3 |
|
Copper products (M) |
See labels (product dependent) |
4 h - 48 h (product dependent) |
1/3 |
|
Oxidate 2.0 (NC) |
1% v/v |
4 h (or when dry) |
1/3 |
Downy Mildew: Infections
are appearing at many locations. If you have significant
infections visible you should consider using Phostrol. Continue to pay close attention to your vines. If you have good control and considering the recent rains,
use good, locally systemic forward protection products such as Revus, Forum, Zampro or Torrent. Be sure you are rotating between chemical groups for proper resistance management. Revus, Forum and Zampro are all from the same fungicide group (group 40) and should not be used in back-to-back sprays. Use Torrent (Group 21) in your next application if you used one of these group 40 fungicides last time. Alternatively, use one of these group 40 fungicides if Torrent was applied last round.
Table 3. Fungicides available for use in vineyards to manage powdery
and downy mildew the 2023 season along with rates, re-entry intervals and efficacy ratings.
|
Product |
Group |
Rate (/ha) |
Re-Entry
Interval **
|
Activity on Powdery Mildew |
Activity on Downy Mildew |
|
Cevya |
3 |
250 mL |
12 h |
3/3 |
0/3 |
|
Fullback |
3 |
731 mL |
12 h / 7 d |
3/3 |
0/3 |
|
Mettle |
3 |
365 mL |
12 h / 15 d |
3/3 |
0/3 |
|
Nova |
3 |
200 g |
12 h / 7 d |
3/3 |
0/3 |
|
Aprovia Top |
3+7 |
643 mL |
12 h / 2 d |
3/3 |
0/3 |
|
Inspire Super |
3+9 |
836 mL |
7 d |
3/3 |
0/3 |
|
Priwen |
5 |
600 mL |
12 h / 17 d |
3/3 |
0/3 |
|
Cantus |
7 |
315 g |
12 h |
3/3 |
0/3 |
|
Sercadis |
7 |
250 mL |
12 h |
3/3 |
0/3 |
|
Luna Tranquility |
7+9 |
600 mL |
12 h / 24 h |
3/3 |
0/3 |
|
Pristine |
7+11 |
735 g |
Dry / 21 d |
3/3 |
2/3 |
|
Merivon |
7+11 |
300 mL |
Dry / 21 d |
3/3 |
2/3 |
|
Miravis Prime |
7+12 |
1.0 L |
12 h |
3/3 |
0/3 |
|
Property |
50 |
366 mL |
12 h |
3/3 |
0/3 |
|
Vivando |
50 |
750 mL |
12 h |
3/3 |
0/3 |
|
Gatten |
U13 |
690 mL |
12 h |
3/3 |
0/3 |
|
Diplomat |
19 |
926 mL |
When Dry |
3/3 |
3/3 |
|
|
|
|
|
|
|
|
Torrent |
21 |
200 mL |
12 h |
0/3 |
3/3 |
|
Forum |
40 |
450 mL |
12 h |
0/3 |
3/3 |
|
Revus |
40 |
500 mL |
12 h |
0/3 |
3/3 |
|
Zampro |
40+45 |
1.0 L |
12 h |
0/3 |
3/3 |
|
|
|
|
|
|
|
|
Copper Products |
M |
See label |
4-48 h |
2/3 |
2/3-3/3 |
|
Sulphur Products |
M |
4-5 kg |
24 h |
3/3 |
0/3 |
|
Oil Products |
M |
1% v/v |
12 h |
2/3 |
0/3 |
|
Manzate |
M |
3 kg |
12 h / 7 d |
0/3 |
3/3 |
|
Folpan |
M |
1.25 kg |
24 h |
0/3 |
3/3 |
|
Captan |
M |
3.0 kg |
12 h / 55 d |
0/3 |
3/3 |
|
Maestro |
M |
3.0 kg |
12 h / 55 d |
0/3 |
3/3 |
|
|
|
|
|
|
|
|
LifeGard |
P6 |
333 g |
4 h |
1/3 |
3/3 |
|
Stargus |
BM2 |
4.0 L |
4 h |
0/3 |
2/3 |
|
Serifel |
BM2 |
500 g |
4 h |
2/3 |
0/3 |
|
Serenade |
BM2 |
3.3 kg |
When Dry |
1/3 |
0/3 |
|
Oxidate |
NC |
1% v/v |
4 h |
1/3 |
1/3 |
|
ProBLAD |
BM1 |
3.3 L |
When Dry |
3/3 |
0/3 |
|
Timorex
Gold |
46 |
2.0 L |
4 h |
2/3 |
1/3 |
Group 11 fungicides (Sovran, Flint & Intuity) are left out of this chart due to resistance concerns.
** REI for General Tasks / REI for Hand Labour
Organic growers should continue using products like LifeGard or Stargus against downy mildew and can mix in a copper product if you have some infections with active sporulation starting to express. There are no resistance concerns with these new biological fungicides so back-to-back sprays are acceptable and encouraged to maintain high levels of disease resistance within the plant. There is also no limit on the number of applications you can make with LifeGard or Starus. These products appear to be quite effective in vineyard blocks that have been routinely incorporating these products in their spray programs since the 5-leaf stage. If active sporulation starts to become visible on leaves or berries, it is recommended to incorporate a product like Copper 53W instead of Cueva since there are greater levels of copper in the Copper 53W formulation which will be more efficient in eradicating downy mildew spores on contact than a copper octanoate product like Cueva will.
Powdery
Mildew: The frequent
rains have kept powdery mildew at bay, but the recent warm humid
conditions are ideal for its development and spread. Be sure to have a good look at the newly developing berries to identify powdery mildew
infections that may have taken place during the bloom and immediate post-bloom period. This is often the time when these early berry infections start to appear and these need to be identified and dealt with immediately before secondary infections take place.
For vinifera growers with vines they are trying to renew with suckers, be sure
to monitor susceptible cultivars like Chardonnay and Riesling. Early infections will always be found in these blocks first. If active powdery mildew infections are identified, it is recommended to expose bunches by continuing with basal leaf removal activities and immediately follow- up with an eradication spray consisting of a bicarbonate product such as MilStop or Sirocco plus Sulphur using lots of water to maximize spray coverage around the berries.
For conventionally managed blocks, select strong locally systemic fungicides for powdery mildew protection. Remember that maintaining good fungicide rotations and using proper application rates are the most important strategies to avoid developing fungicide resistance. If you used a group 7 product for your post-bloom spray (Luna Tranquility, Cantus, Sercadis or Miravis Prime), rotate to a product like Vivando, Property, Gatten or Cevya for your next application. Priwen is another option if you do not have any hand labour to do since there is a 17-day REI for hand labour activities with this product. All the other listed options only have a 12-hour REI for hand labour tasks. It is highly recommended to AVOID using group 11 fungicides such as Sovran and Flint during this pressure time as there is a high degree of local resistance identified against powdery mildew and you will see failures with these products if they are relied on for powdery protection alone.
For organically managed vinifera blocks, continue relying on Sulphur as your primary fungicide targeting powdery mildew. Incorporating either LifeGard or Serifel will enhance your powdery mildew defence and is highly recommended in susceptible cultivars or in blocks with a history of powdery mildew.
Before choosing to use any
product, be sure to check the most recent version of the label either provided
by your supplier or available from https://pr-rp.hc-sc.gc.ca/ls-re/index-eng.php
Recommendations in this blog are given for general information
only and do not give the user the right to use a product in a manner not in
accordance with the pesticide label or Pest Control Products Act. Perennia, by
funding and printing this publication, does not offer any warranty or guarantee
and does not assume any liability for crop loss, animal loss, health, safety or
environmental hazard caused by the use of any pesticide or recommendation in
this schedule. Pesticides used in this schedule are products labeled for the
target and crop. This information was retrieved from the Pest Management
Regulatory online Registered Products Database. The list of products presented
in this schedule is intended to be complete, but in no way is guaranteed to be
complete. Some of the products listed may not be available. Trade names are
given as a convenience to producers and are neither an endorsement of the
product nor a suggestion that similar products are not available or effective.
All products listed in this guide are registered for use in
Canada; however, foreign markets may have specific restrictions on which
pesticides can be used on the crop they are buying. It is a good idea to check
with the receiving shed or processor you are selling to, for an allowable
inputs list.