It is extremely important to know which pathogen is causing damping-off problems and which fungicide to properly apply. The key to controlling damping-off is being proactive instead of reactive. Always refer to the fungicide label for crop use, pathogens controlled, and application rates.

Damping-off is caused by a number of important vegetable pathogens and is very common during the spring. Damping-off can kill seedlings before they break the soil line (pre-emergent damping-off) or kill seedlings soon after they emerge (post-emergent damping-off). Common pathogens that cause damping-off include Pythium, Phytophthora, Rhizoctonia and Fusarium spp.

Control of damping-off depends on a number of factors. First, is recognizing the conditions which may be leading to the problem (i.e., weather/greenhouse growing conditions) and second, identifying the pathogen causing the problem.

Conditions Favoring Damping-off

Although all four pathogens are associated with damping-off, the conditions which favor their development are very different. In general, Phytophthora and Pythium are more likely to cause damping-off in cool, wet or overwatered soils that aren’t allowed to dry out due to cloudy weather or cooler temperatures. Conversely, Rhizoctonia and Fusarium are more likely to cause damping-off under warmer, drier conditions especially if plug trays are kept on the dry side to help reduce transplant growth. [Read more…]

Sweet Corn

Most of the IPM Program black light trap network is now operational in New Jersey.   To date, no corn earworm (CEW) have been captured.  However, low numbers of European corn borer (ECB) moths are now appearing in a number of traps (see map at left).  This is the onset of the first flight of the season.  As yet, most corn is too young to support an infestation, although early plantings grown under plastic will be at risk first.   As numbers increase and corn plantings progress into the whorl stage, growers should begin scouting for injury.  Look for the characteristic “shot-hole” type of feeding (photo below at right) and consider treating when infested plants exceed 12% in a 50 plant sample.

The highest nightly trap catches of ECB for the week ending 5/15/19 are as follows:

[Read more…]

Sweet Corn

IPM Program personnel are currently finishing deployment of the black light trap network in New Jersey.  At present, we are approximately 80% operational and have begun to monitor traps.  To date, no corn earworm (CEW) have been captured.  The low numbers of European corn borer (ECB) moths that have been caught do not allow us to produce a map image.  As numbers increase, look for population maps of ECB, CEW and CEW catches from pheromone traps in this weekly publication.  The Vegetable IPM Program is expanding the use of CEW pheromone traps to include central and northern counties this year.  The resulting full-state maps will include interpretive information.

The highest nightly trap catches of ECB for the week ending 5/08/19 are as follows:

Georgetown   1              Woodstown   1

Hillsborough   1

European corn borer egg mass on a pepper leaf.

[Read more…]