Disease Management
Refer to the following chart that outlines most of the mildew fungicides available for use this season along with rates, re-entry & pre-harvest intervals, and mildew efficacy ratings. Mildew fungicides that will also protect against botrytis are indicated with an asterisk *.
|
Fungicide Name |
Group |
Rate (/ha) |
Re-Entry Interval** |
Pre-Harvest Interval |
Activity on Powdery Mildew |
Activity on Downy Mildew |
|
Cevya |
3 |
250 mL |
12 h |
14 d |
3/3 |
0/3 |
|
Fullback |
3 |
731 mL |
12 h / 7 d |
14 d |
3/3 |
0/3 |
|
Mettle |
3 |
365 mL |
12 h / 15 d |
15 d |
3/3 |
0/3 |
|
Nova |
3 |
200 g |
12 h / 7 d |
14 d |
3/3 |
0/3 |
|
Aprovia Top |
3+7 |
643 mL |
12 h / 2 d |
21 d |
3/3 |
0/3 |
|
Inspire Super * |
3+9 |
836 mL /1.48
L * |
7 d |
14 d |
3/3 |
0/3 |
|
Priwen |
5 |
600 mL |
12 h / 17 d |
35 d |
3/3 |
0/3 |
|
Cantus |
7 |
315 g |
12 h |
14 d |
3/3 |
0/3 |
|
Sercadis |
7 |
250 mL |
12 h |
14 d |
3/3 |
0/3 |
|
Luna Tranquility
* |
7+9 |
600 mL /1200 mL * |
12 h / 24 h |
7 d |
3/3 |
0/3 |
|
Pristine |
7+11 |
735 g |
Dry / 21 d |
14-21 d |
3/3 |
2/3 |
|
Merivon |
7+11 |
300 mL |
Dry / 21 d |
14-21 d |
3/3 |
2/3 |
|
Miravis Prime
* |
7+12 |
1.0 L * |
12 h |
14 d |
3/3 |
0/3 |
|
Property |
50 |
366 mL |
12 h |
0 d |
3/3 |
0/3 |
|
Vivando |
50 |
750 mL |
12 h |
14 d |
3/3 |
0/3 |
|
Gatten |
U13 |
690 mL |
12 h |
14 d |
3/3 |
0/3 |
|
Diplomat |
19 |
926 mL |
When Dry |
0 d |
3/3 |
3/3 |
|
|
|
|
|
|
|
|
|
Torrent |
21 |
200 mL |
12 h |
30 d |
0/3 |
3/3 |
|
Forum |
40 |
450 mL |
12 h |
14 d |
0/3 |
3/3 |
|
Revus |
40 |
500 mL |
12 h |
14 d |
0/3 |
3/3 |
|
Zampro |
40+45 |
1.0 L |
12 h |
14 d |
0/3 |
3/3 |
|
|
|
|
|
|
|
|
|
Copper Products |
M |
See label |
4-48 h |
1-2 d |
2/3 |
2/3-3/3 |
|
Sulphur Products |
M |
4-5 kg |
24 h |
21 d |
3/3 |
0/3 |
|
Oil Products |
M |
1% v/v |
12 h |
12 h |
2/3 |
0/3 |
|
Manzate |
M |
3 kg |
12 h / 7 d |
66 d |
0/3 |
3/3 |
|
Folpan |
M |
1.25 kg |
24 h |
1 d |
0/3 |
3/3 |
|
Captan |
M |
3.0 kg |
12 h / 55 d |
7-55 d |
0/3 |
3/3 |
|
Maestro |
M |
3.0 kg |
12 h / 55 d |
7-55 d |
0/3 |
3/3 |
|
|
|
|
|
|
|
|
|
LifeGard |
P6 |
333 g |
4 h |
4 h |
1/3 |
3/3 |
|
Stargus |
BM2 |
4.0 L |
4 h |
4 h |
0/3 |
2/3 |
|
Serifel |
BM2 |
500 g |
4 h |
0 d |
2/3 |
0/3 |
|
Serenade |
BM2 |
3.3 kg |
When Dry |
0 d |
1/3 |
0/3 |
|
Oxidate |
NC |
1% v/v |
4 h |
4 h |
1/3 |
1/3 |
|
ProBLAD |
BM1 |
3.3 L |
When Dry |
0 d |
3/3 |
0/3 |
|
Timorex Gold |
46 |
2.0 L |
4 h |
2 d |
2/3 |
1/3 |
Group 11 fungicides
(Sovran, Flint
& Intuity) are
left out of this chart
intentionally due to resistance concerns.
** REI for General Tasks / REI for Hand Labour
Powdery Mildew. Recent weather conditions have been ideal for infections to take place and, as a result of the frequency of recent rain events, it has been difficult to get any protective sprays on this past week. Berries remain susceptible to powdery mildew infections until veraison is easily identified (1-2 more weeks) which means that early cultivars will reach this natural resistant stage before our later maturing cultivars will.
If you identify active powdery mildew infections on fruit or leaves, a ‘special spray’ would be warranted in those blocks to help eradicate these infections. Secondary infections can easily occur once primary infections begin to express and something as little as a light rain or a heavy dew can be enough to move spores to nearby tissues.
If you have infected fruit,
dropping heavily infected bunches and applying a bicarbonate spray are the recommended practices that will help to reduce the potential for secondary spread.
Bicarbonate sprays should be focused on
where these infections are being observed. Remember bicarbonate sprays only work on active sporulation
and do not provide forward protection.
Conventional growers with good control of powdery mildew should continue to
rely on effective locally systemic products and maintain useful product rotations for resistance management.
The REI for Priwen is 17-days for hand labour (12-hours for a general REI) and the PHI is 35-days so this would be the last opportunity to use this product for early maturing cultivars. Remember to avoid the use of group 11 fungicides such as Sovran and Flint as there are major resistance concerns surrounding this group of fungicides
and powdery mildew control. For organically managed 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.
Downy Mildew is
appearing everywhere.
If new active downy mildew sporulation is easily visible, incorporate some Phostrol (or phosphorus
acid products such as Confine Extra, Rampart) in your tank mix to provide some eradication of these infections. The application rates of Phostrol are dependent on the water volumes being used. Use a concentration rate of 580 mL of Phostrol for every 100 L of water used per hectare. That correlates to 2.9L of Phostrol in 500 L of water per ha OR 5.8 L in 1000 L of water per ha. Check for label rates of Confine Extra and Rampart. Do not rely on
Phostrol, Confine Extra and Rampart to give you forward protection. These
products are only effective for Downy Mildew.
Remember you are allowed a maximum of 4 Folpan applications per season.
Locally systemic fungicides specifically for downy mildew include Revus (40), Forum (40), Torrent (21) and Zampro (40+45). Another option is to use a broad- spectrum fungicide like Diplomat which will provide activity against powdery mildew as well as downy mildew. These products are rain-fast once dry and will provide up to 10 days of good protection under dry conditions. Be aware of pre-harvest intervals if you are growing table grape cultivars or early maturing wine grapes. Torrent has the longest pre-harvest interval at 30-days so you should consider using Torrent in
your next application. The group 40 fungicides such as Revus, Forum and Zampro all have a 14-day PHI so reserve those for sprays in mid- to late-August.
Organic growers should continue using products like LifeGard or Stargus against downy mildew until mid-August to maintain elevated levels of disease resistance within the plant. There are no resistance concerns with these new biological fungicides or a limit to how many applications you can use so back-to-back sprays are acceptable. If active sporulation starts to become visible on leaves or berries, it is recommended to incorporate full rates a product like Copper 53Winstead 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.
 |
| Downy Mildew symptoms showing in Chardonnay. |
 |
| Downy Mildew. White cottony-like mold on lower surface of leaf of Chardonnay. |
Botrytis – a concern only if you have a crop, you will harvest and grow cultivars that are susceptible, and you want to spend the money! If you decide to apply a specific botrytis spray, go back in your records to determine what chemical family was used last time (berry touch/cluster closure) and be sure to rotate between chemical groups. Good botrytis materials to use at this growth stage include Inspire Super (3+9), Luna Tranquility (7+9), Scala (9), Miravis Prime (7+12) or Switch (9+12). The use of Inspire Super, Miravis Prime or Luna Tranquility at the botrytis rate will also provide full protection against powdery mildew. If you have already applied Miravis Prime this year, and you wish to spray for botrytis, be sure to avoid using Switch as a follow-up since both these products contain the same active ingredient. Also be aware that Inspire Super, Luna Tranquility and Scala all contain a group 9 component that is active on botrytis and should not be used in back-to-back sprays targeting botrytis.
If you require organic botrytis control, products available for this application include Serenade OPTI, Serifel, Double Nickel, Timorex Gold or Regalia Maxx. ProBlad Biofungicide is another soft product with reliable results against botrytis (and powdery mildew) however, it is not organically certified. As always, be sure to check with your certification body to determine what organic products are acceptable for use.
INSECT MANAGEMENT
Between post-bloom and veraison is the recommended timing for Movento applications targeting Grape Mealybug and Scale insects. If you have identified mealybugs or scales in your vineyard this spring, and are doing a full control program this season, your second Movento application should be applied with your next cover spray. For growers that are planning to apply a single Movento application as a mealybug and scale maintenance spray, and have not applied it yet, be sure to incorporate this into your next spray. The Movento rate on the label ranges from 365-585 mL/ha. Reliable results have been seen using an application rate of 460 mL/ha and this product recommends being applied with a spreader/sticker.
Japanese Beetle Reports
of Japanese beetle started the second week of July, which is earlier than
typically observed in NS. Management can be tricky, since the adults can be
twitchy and quickly get out of the way of spraying or any manipulation of
leaves, etc. Mature vines can usually withstand the feeding pressure because of
the amount of foliage pushed out, especially in hybrids. We are unsure sure how
the vines might respond this year, given everything that they have been
through. The most vulnerable vines will be newly planted or those with limited
shoot growth and those should be managed. Recommendations used in Ontario suggest
a threshold of 25-30% leaf injury or 25 beetles per meter for healthy mature
vines but if new feeding damage is observed on these newer lateral leaves, thresholds should be lowered slightly. Assail/Aceta is also registered against JB and has shown reasonable control
in commercial vineyard use. 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 remains fairly low. Recent rains have helped to stabilize populations and to maintain good vine health, making the vines more resilient to feeding injury developing into visible symptoms. If control is required over the next 7-10 days, consider using Assail/Aceta, Closer, Sivanto Prime or Admire for leafhopper control. These products may also have some effect on any phylloxera crawlers that may be exposed.
At some locations, we are starting to see some new phylloxera galls forming on shoot tips of new Phylloxera activity. In other vineyards, activity is persisting with new galls being observed on newly developing leaves in the upper canopy. Keep a close eye on susceptible cultivars such as Marquette, Baco Noir, Foch, DeChaunac, Chambourcin, GR 7 and Vidal for any continued signs of recent activity. Focus on the young leaves at the top of shoots for presence of new galls that may warrant an insecticide application. If you used (or are using) Movento for Grape Mealybug or Scale management, you will gain some control of phylloxera but, if you see new galls developing on new leaves and require a material just for phylloxera, consider using either Assail/Aceta or Clutch. These are fast acting, effective against young phylloxera crawlers and will additionally provide activity on leafhoppers and Japanese beetle. AAFC Kentville is trapping for soil emergence and has a trial ongoing to look at silica foliar applications and influence on leaf gall formation) and erinea mite.
 |
| Phylloxera damage on upper surface of leaf of Marechal Foch. |
 |
| Phylloxera damage on lower surface of leaf of Marechal Foch. |
 |
| Erineum Mite galls on Geisenheim 318. |