Cucurbit Downy Mildew – New Occurrence
Cucurbit Downy Mildew (CDM) was discovered on cucumbers near Belvidere, Warren County on Friday 7/13. This occurrence is in addition to the previously reported infection sites in Salem County. All growers statewide, should be adding appropriate downy mildew specific fungicides to their protection programs on cucumbers. Look for yellow “panels” on the upper leaf surface, with dark sporulation on the lower leaf surface (see photos at right). It should be noted that, in the Belvidere case, adjacent crops of summer squash and muskmelons were uninfected. Additionally, no pumpkin or winter squash fields are known to be infected at this 
time. Most races of CDM will infect cucumbers, while there are limited strains that will infect other cucurbits like musk and watermelons as well as pumpkins and winter squash. Please refer to the CDM Forecast http://cdm.ipmpipe.org/ for updates on disease outbreaks and forecasts for this disease. Useful fungicides and rotations are to be found in the 2018 Commercial Vegetable Production Guide Cucumber section.
Beet Armyworm
A number of beet armyworm (BAW) pheromone traps are deployed in southern NJ counties each year. BAW has, at times been a troublesome pest of peppers in south Jersey, and occasionally in the north as well. This week one trap in the Woodstown area of Salem County increased from low single digit nightly catches to 15-16 per night. While no field infestations by this pest have been discovered thus far, these moth numbers are a warning to all pepper growers in the area that fields should be scouted at least weekly. BAW can cause extreme defoliation of plants, beginning near the upper terminals (see photo at lower right, courtesy of Univ. of Georgia). If left untreated, the larvae will consume much of the foliage and bore into fruit. BAW are largely resistant to synthetic pyrethroid insecticides. Effective insecticides include those in the IRAC classes 5 (Radiant, Entrust 
(OMRI approved)) and 28 (Coragen, Exirel). For a complete list of useful insecticides, see the Pepper section of the 2018 Commercial Vegetable Production Guide.
