The 2019 Wine Grape Twilight Meetings are being held in South Jersey on Wednesday, May 22 and North Jersey on Thursday, May 23.
See flyer for details.
Rutgers Cooperative Extension
Seasonal updates on diseases, insects, weeds impacting tree fruit and small fruit (blueberry, cranberry, and wine grape). Fruit Pest Alerts are also available via this category feed.
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The 2019 Wine Grape Twilight Meetings are being held in South Jersey on Wednesday, May 22 and North Jersey on Thursday, May 23.
See flyer for details.
Peach:
Oriental Fruit Moth: First generation timings are updated below:
OFM 1st Degree Day (DD) Timing | ||||
Insecticide Type | ||||
County/Region | Biofix | DD by 5/1 base 45 | Conventional
170-200, 350-375 |
Diamide
100-150, 300-350 |
Gloucester – Southern | 4/8 | 344 | 1st – past
2nd – 5/1-5/2 |
1st – past
2nd – 4/27-5/1 |
Hunterdon – Northern | 4/16 | 173 | 1st – 5/1-5/2
2nd – about 5/12-16 |
1st – past
2nd – about 5/9-12 |
Peach:
Oriental Fruit Moth: First generation timings are updated below:
OFM 1st Generation Timing | |||
Insecticide Type | |||
County/Region | Degree Days by 4/23 base 45 | Conventional
170-200, 350-375 |
Diamide
100-150, 300-350 |
Gloucester – Southern | 254 | 1st – 4/18-20
2nd – 4/29-5/1 |
1st – past
2nd – 4/25-4/29 |
Hunterdon – Northern | 186 | 1st – 4/28-5/2
2nd – 5/8-5/12 |
1st – 4/23-4/26
2nd 5/3-5/7 |
Plum Curculio Biology and Management in New Jersey Peaches
Dr. Anne Nielsen, Tree Fruit Entomologist
Dr. Clement Akotsen-Mensah, Postdoctoral Research Associate
Plum curculio (PC)continues to be a major pest of peach, apple, plum, cherry and blueberry, and can cause significant crop losses through early season scarring of the fruit. Untreated peach blocks in NJ can have >90% injury through scarring, direct fruit loss, and larval contamination of the fruit. In recent years, we have observed that more applications are needed for control to bring PC populations to manageable levels, particularly in peaches. This is because of 1) extended period of PC activity, 2) less effective insecticides, or 3) presence of the Southern population which has at least 2 generations per year.
There is a lot of seasonal variations in major plant phenological events like time of bloom and petal fall within NJ, we can use degree-day accumulation and plant phenology to better predict activity and injury. We present results from series of research conducted in the laboratory and in research plots to help unravel the population structure and (unbaited) trap based degree-day model of PC in NJ peaches. Also, pest phenological events have been determined and a degree-day model developed which is being validated in peach orchards.
Table 1. Phenological events recorded in experimental peach orchard in 2017 and 2018 peach seasons in New Jersey
Biofix at January 1 and LTDT at 10°C (50°F) | |||
Phenological event | 2017 | 2018 | Mean |
First trap catch | 89 | 96 | 93 |
First peak trap catch | 123 | 167 | 145 |
First egg lay in fruit | 247 | 295 | 271 |
Peak egg laying | 383 | 399 | 391 |
Peak larval emergence | 547 | 515.5 | 531 |
Peak trap catch of second generation | 1256 | 961 | 1108 |
Plum Curculio Management
Insecticide treatments continue to be the main management tool for plum curculio. Insecticides are applied to the whole block targeting critical phenological events such as petal fall, peak of oviposition, and emergence of the second generation. Insecticides used (Table 2) will target the adults migrating from overwintering or egg laying. The model predicts plum curculio will start migrating from overwintering sites into peach orchards at a degree-day of 88-100DD using January 1 as biofix and 10°C as lower development temperature threshold (Table 1). The peak trap capture of the overwintering population occurs within 113-176DD. The peak egg lay in peach occurs in a range of 379-402 DD.
Growers typically begin insecticide applications against plum curculio in peach at petal fall and repeat every 7 to 14 days as long as new damage appears or until 400DD in apple (post golden delicious petal fall).
Our model provides additional decision making using pyramid trap numbers and degree-day accumulations. We predict the first application (whole block) using a plum curculio adulticide (Imidan, Avaunt, Asana, Harvanta, or Apta) to occur before the peak trap capture at 113-176 DD. This application should be made as long as the phenology of the plant permits (after petal fall). A second application (using Actara, Belay, Rimon (apples)) should be made before the peak egg laying (379-402 DD) to kill eggs. Applications should continue on 7-14 day schedule if activity and pressure warrant management. If needed, application using Imidan, Avaunt, Asana, Harvanta or Apta at the peak of the second generation 900-1317 DD.
Table 2: List of insecticides that are used to control plum curculio on pome and stone fruit (Rutgers Cooperative Extension Commercial Tree Fruit Production Guide 2016)
Compounds | Chemical class / activity | Crop | Life Stage targeted |
Imidan 70W | Organophosphate (phosmet) | Pome fruit
Stone fruit |
Adults |
Lethal via contact | |||
Actara 25WG | Neonicotinoid (thiamethoxam) | Pome fruit
Stone fruit |
Adults
Eggs |
Lethal, Antifeedant and Curative | |||
Belay 2.13SC | Neonicotinoid (clothianidin) | Pome fruit
Peach |
Adults
Eggs |
Lethal, Antifeedant and Curative | |||
Avaunt 30WG | Oxadiazine (indoxacarb) | Pome fruit
Stone fruit |
Adults |
Lethal via ingestion | |||
Asana, Warrior, Baythroid | Pyrethroids | Pome fruit
Stone fruit |
Adults |
Lethal, repellent | |||
Rimon (targeting codling moth, obliquebanded leafroller) | IGR (novaluron) | Apple | Eggs |
Egg sterilization | Stone fruit | ||
Harvanta | Diamide | Apple | Adults
(maybe eggs) |
The mention of a product does not mean endorsement of this product. Growers are required to strictly follow all labels.
Self-pollination or cross-pollination between undomesticated cranberries and selected cultivars occur frequently and produce fruits containing fertile seeds. Seedlings germinating from these seeds are off-type varieties that may have lower fruit yield potential and higher vegetative vigor. Contamination by off-type varieties may result in decreased long-term productivity of planted cranberry beds and loss of profitability for the New Jersey cranberry industry in an increasingly competitive environment.
In response to questions from New Jersey growers on the efficacy of preemergence herbicides at controlling off-type cranberry seedlings, we recently conducted an experiment at the Marucci Center for screening currently labeled preemergence herbicides.
Seeds were collected from three different varieties (Haines, Mullica Queen, and Stevens), stratified at 3°C for 2 months, and seeded on Petri dishes containing preemergence herbicide mixed in agar. The trial was replicated 5 times and two different runs were conducted during the winter 2018-2019. Cranberry seed germination was quantified several times a week and the experiment was terminated by 40 days after seeding cranberry seeds.
Results: Callisto, regardless of rate applied, did not provide any control of cranberry seed germination compared to the untreated check. Similarly, Evital 5G did not reduce seedling emergence more than 17% when used at the highest labeled rate (160 lb/A). Devrinol DF-XT had higher activity, reducing seed germination by 30% at 12 lb/A and by 50% at 18 lb/A. However, only the 12 lb/A rate is labeled for sandy beds. Casoron 4G was the most effective treatment with complete inhibition of cranberry seed germination at 50 or 100 lb/A. Similar results were noted by Dr. Jed Colqhoun in Wisconsin on cranberry grown on peat plugs for Casoron and Callisto. However, Devrinol was noted having no activity on cranberry seed germination in the WI study. This might be caused by organic matter binding of the herbicide in peat plug, which is less of a problem in agar. The study will be continued this summer by looking at germination of seed grown in a mix of sand and peat moss and treated with some of the preemergence herbicides mentioned here.
These results highlight the need for rotating preemergence herbicide with different modes of action, not only for preventing the onset of herbicide resistant weed species, but also for expanding the spectrum of weeds controlled by these herbicides, including off-type cranberry seedlings.