Potato Disease Advisory #18 – July 6, 2012

Phillip Sylvester, Kent Co., Ag Agent; phillip@udel.edu

Late blight Advisory
Location: Art and Keith Wicks Farm, Rt 9, Leipsic, Kent County, Delaware
Greenrow: April 20

Date

DSV

Total DSV

Accumulated
P-Days

Spray Interval Recommendation

6/4-6/6

0

71

355

10-days

6/7-6/11

0

71

395

10-days

6/11-6/14

8

79

424

7-days

6/15-6/18

0

79

460

10-days

6/19-6/21

1

80

478

10-days

6/22-6/25

2

82

507

10-days

6/25-6/27

0

82

524

10-days

6/28-7/2

0

82

549

10-days

7/3-7/5

0

82

561

10-days

 

The spray interval recommendation is 10 days. The hot and dry weather we continue to experience should reduce the threat of late blight. There have been no reports in Delaware. Visit http://www.usablight.org/ to see where late blight has been found on potato and tomato in the region.

Commercial fungicide recommendations can be found in the 2012 Delaware Commercial Vegetable Recommendations Guide at http://ag.udel.edu/extension/vegprogram/pdf/potatoes.pdf.