Lettuce – Downy mildew

Crop(s):          Lettuce

Disease(s):     Downy mildew

Resistance management strategy for:

Guidelines:

1. Applications made within the nursery count towards the total number of applications allowed per crop. It is recommended that disease control is started early and maintain a regular program using a fungicide from groups other than Group 4, 40, 45+40, 49 (or 49+11) or 28+43.
2. When conditions favour disease development, do not wait for disease to appear, but apply two consecutive sprays of a Group 4, 40, 49, 49+11 or 28+43 product at the interval recommended on the label. Then resume the program of sprays using an alternative fungicide group to what was just applied.
3. Do not apply more than four sprays of a Group 4 or 40 product per season.
4. Do not apply more than four sprays of a Group 45+40 product per crop.
5. Apply Group 45+40 fungicides preventatively.
6. Group 49 including Group 49+11 fungicides should only consist of a maximum of one in every three of the total fungicide sprays per crop targeting downy mildew. Do not apply more than three sprays of a Group 49 containing product including Group 49+11 sprays per crop. Group 49+11 sprays count as both a Group 49 and a Group 11
7. Do not apply more than three sprays of a Group 28+43 product per crop.
8. Apply Group 4 and 49 (or 49+11) fungicides preventatively and only in mixtures or co-formulations with a registered fungicide from a different mode of action group, with no known resistance.
9. 1. Continue alternation of fungicide modes of action between successive crops. Do not make more than (6) six total applications of a Group 49 product on multiple crops per year, on the same area, targeting the same disease.

   	Group
   	4	28+43	40, 45+40	49, 49+11
   Maximum number of consecutive applications	2	2	2	2
   Maximum number of solo sprays	None			None of 49
   Maximum number of sprays per crop or season including nursery *	4	3^ (or 1 in 3)	2 or 4	3 ^ (or 1 in 3) 6 per year

   * Maximum application number on product label may differ. Ensure you follow the label recommendations

   ^Not allowed in nursery situations