May 10, 2017

Veg IPM Update: Week Ending 5/10/17

Sweet Corn

Cold temperatures are slowing corn growth considerably.  The same weather is also delaying the onset of pests like the European corn borer (ECB).  No ECB were captured in blacklight traps this week.  As the population develops, look for maps to be published in the weekly IPM Update.

Cole Crops

Although cold weather and heavy rains have suppressed them, IPM personnel continue to observe infestations of crucifer flea beetle.  These beetles can build to high populations quickly, especially where wild mustard and related cruciferous weeds are common.  Extreme feeding on small transplants can cause irreversible damage if not controlled promptly. [Read more…]

Filed Under: Vegetable Crops Tagged With: ,
May 3, 2017

Veg IPM Update: Week Ending 5/03/17

Sweet Corn

The Vegetable IPM blacklight trap network is nearly complete.  With limited numbers of traps having been checked, only one European corn borer (Allentown, Mercer County) and one corn earworm (Old Bridge, Middlesex County) have been recorded.  As sweet corn is currently in the seedling stage, neither of these catches represent a threat.  As catches become more consistent, maps of the adult populations of these two pests will be published in the weekly IPM Update.

Cole Crops

With warm, sunny days, IPM personnel have discovered a number of heavy infestations of crucifer flea beetle.  These beetles can build to high populations quickly, especially where wild mustard and related cruciferous weeds are common.  Extreme feeding on small transplants can cause irreversible damage if not controlled promptly. [Read more…]

Filed Under: Vegetable Crops Tagged With:
January 18, 2017

Corn Earworm Developing Resistance to Bt Toxins in Sweet Corn

Corn earworm caterpillar feeding on sweet corn tassel

New research from the University of Maryland indicates that corn earworm, also known as tomato fruitworm, has developed resistance to the Cry1 Bt toxins present in some sweet corn hybrids.  Based upon Galen Dively’s twenty-one years of research comparing non-Bt sweet corn varieties with Bt varieties in plot studies, the proportion of damaged ears in Bt varieties has dramatically increased over that time.

Syngenta sweet corn hybrids with Attribute® technology expressing Cry1 Ab toxins in 1996 showed less than 10% ear damage.  Those hybrids with Attribute® in 2016 averaged 84% ear damage.  Similarly, the amount of damaged area per ear had tripled.

Seminis produced sweet corn hybrids with Performance SeriesTM containing Cry1 A.105 and Cry2 ab for worm control.  When some of these hybrids were first evaluated in 2010 they provided 100% control of fall armyworm and 95% control of corn earworm.  In 2016, six plantings at research farm sites of these hybrids averaged 67% damaged ears.

[Read more…]

Filed Under: Vegetable Crops Tagged With: ,
October 5, 2016

Veg IPM Update: Week Ending 10/05/16

Sweet Corn

16cew1005aCorn earworm moth (CEW) activity has been fairly steady over the past week.  Patches of locally higher activity remain within a generally low population (see CEW map).  Catches are now rising and falling with night time temperatures.  It is advisable to incorporate materials into the spray program that have different modes of action from the pyrethroids.  This includes IRAC 28 materials like Coragen, Exirel and Besiege, as well as IRAC 5 (Radiant, Entrust (OMRI approved), and Blackhawk)).  Growers should be checking CEW activity frequently, and adjust spray schedules according to local activity.  On this map, green areas correspond to a 3-4 day silk spray schedule, while blue is 4-5 days.

The highest nightly CEW catches for the previous week are as follows:

Centerton   3 Denville   1 Milford   1
Green Creek   2 Eldora   1 New Egypt   1
Blairstown   1 Farmingdale   1 Sergeantsville   1
Califon   1 Jones Island   1 Tabernacle   1

 

 

[Read more…]

Filed Under: Vegetable Crops Tagged With: , , , ,
September 28, 2016

Veg IPM Update: Week Ending 9/28/16

Sweet Corn

European corn borer (ECB) moths are nearly non-existent now.  There are no particular areas of higher activity, and  no map will appear in this edition. It is unlikely that we will realize any further injury from this pest this season.

Nearly all remaining sweet corn plantings are now in the silk stage.  Fall armyworm (FAW) however, continues to be a threat to these sweet corn plantings.  We should expect this pest to be with us at some level for the remainder of the sweet corn growing season.   FAW do not respond well to pyrethroid insecticides.  The most useful products are those in the IRAC group 28 class (Coragen, Exirel) or the IRAC group 5 class (Radiant, Entrust), or combination products including these classes.  See the 2016 Commercial Vegetable Recommendations Guide for insecticides effective against FAW.

  [Read more…]

Filed Under: Vegetable Crops Tagged With: , , , ,
September 21, 2016

Veg IPM Update: Week Ending 9/21/16

Sweet Corn

European corn borer (ECB) moth numbers have decreased this past week such that only a handful of moths were captured.  There are no particular areas of higher activity, and  no map will appear in this edition. It is unlikely that we will realize any further injury from this pest this season.

The highest nightly ECB catches for the previous week are as follows:

Cinnaminson   1 Milltown   1
Clinton   1 Pedricktown   1
Hillsborough   1 Sergeantsville   1

[Read more…]

Filed Under: Vegetable Crops Tagged With: , , , ,