Archives for July 2023

July 12, 2023

Diagnosing Collar Rot and Alternaria Stem Rot of Tomato

Collar rot (Alternaria linariae) or Alternaria stem rot (Alternaria alternata f. sp. lycopersici) of tomato are common in young tomato plants. Either can be particularly troublesome in seedlings that have been held in transplant flats for an extended period of time before transplanting in hot, humid greenhouses. Collar rot infections often start where a leaflet branch has been broken or pruned which allows a point of infection. Symptoms of Alternaria stem rot include brown circular to irregular lesions on stems with definitive concentric black rings (very similar to Early blight on infected leaves). Symptoms of Collar rot are similar and may or may not produce concentric black rings. Infections that start in the greenhouse may lead to losses in the field as stems become girdled causing the plant or branches to wilt and die. Most commercial tomato varieties have resistance to Alternaria stem rot. While resistance is lacking to Collar rot, growers should chose varieties with Early blight resistance. Fungicides used to control Early blight are also effective against Collar rot.

Symptoms of Collar rot in young tomatoRotten stem

 

 

Filed Under: Vegetable Crops Tagged With: ,
July 11, 2023

Landscape Pest Notes for July 2023

Cooley Spruce Gall Adelgid (1850-1950 GDD = galls open): Colorado spruce (especially green forms), Sitka and Oriental spruce, and Douglas-fir share this pest’s two host life cycles. Mature adult females lay eggs at the tips of branches. These eggs hatch and the immatures move to new growth and start feeding. The combined feeding and salivary secretions induce the development of a bright green, oval “pineapple” gall on the terminals (as opposed to galls at the base of new growth on Norway spruce from the Eastern spruce gall adelgids). By midsummer, the gall will turn brown and crack open, as the adelgids within mature and emerge as adults. These winged adults migrate to Douglas-fir (or another spruce) and spend the remainder of the summer feeding on the needles, covered with cottony wax.

Coolly Spruce Gall Adelgid = dead, open gall

During late July or early August the adult Cooley spruce gall adelgids will emerge from the opened brown pineapple shaped galls. (Photo Credit: Steven K. Rettke, Rutgers Coop. Ext.)

Sometimes Douglas-fir is so heavily attacked that needles are spotted, bent, or distorted. Two or more generations can occur on Douglas-fir through the following season (Christmas tree growers will treat Douglas fir when new growth is 3-4 inches). By next fall another winged generation flies back to spruce and lays eggs for the cycle to repeat itself.

Cooley spruce gall adelgid on Douglas-fi

After the Cooley spruce gall adelgid winged adults emerge from the “pineapple” galls on spruce some will relocate & infest Douglas-fir needles. They will remain on this host for the remainder of the summer. (Photo Credit: Steven K. Rettke, Rutgers Coop. Ext.)

Control by pruning out galls when seen before they open in mid-summer. Place sticky traps out in  summer (Douglas-fir or spruce) (1850-1950 GDD) to determine the timing to spray adults with insecticidal soap (+ sticker). In southern NJ some of the tip “pineapple” galls on spruce will soon open up, and the winged adults will emerged. Except to improve the aesthetic appearance of the trees, there is nothing to be gained by picking off the galls after they have opened. Future control windows will occur during the fall or early spring months, against the overwintering females located at the bases of terminal buds. Some possible treatments include horticultural oil, carbaryl (Sevin), insecticidal soap, or imidacloprid (Merit).

The Landscape Pest Notes for July 2023 contains only insect/mite pests & a couple of predators commonly seen during the month. Contained below are 16 additional pests or predators that appear in the order they are listed as follows: Pine needle scale, Fall webworm, Obscure scale, Pitch mass borer, Two banded Japanese weevil, Aphids, Cicada killer, Juniper webworm, Sapsucker, White pine weevil, Peach tree borer, White waxy lady beetle, Japanese beetle, Oriental beetle, Dogwood sawfly, & Plant leaf galls. [Read more…]

Filed Under: Landscape, Nursery, & Turf, Nursery, Plant Diagnostic Lab
July 11, 2023

Controlling Phytophthora blight in cucurbit plantings

As the summer heats up in New Jersey, the control of Phytophthora blight in cucurbit plantings can be extremely difficult (even with the use of fungicides) as hot, wet weather finally sets in. Mitigating losses to Phytophthora blight in cucurbit crops begins with long crop rotations,  where recommendations suggest crop rotations longer than 5 years if possible. Other cultural practices include avoid planting in low areas of the field where water may persist after rain or overhead irrigation, rogueing out infected plants as soon as possible, cutting the plastic to help dry out the soil, proper weed control, and proper preventative fungicide programs.

[Read more…]

Filed Under: Vegetable Crops Tagged With: , ,
July 11, 2023

Diagnosing pith necrosis in tomato

Symptoms usually begin to appear on random plants throughout the field as green fruit begins to mature. The bacterium (Pseudomonas corrugata) is ubiquitous to soils and develops when weather conditions (cooler nights/very hot, humid days) and cultural practices (i.e., excess heavy N use) lead to favorable conditions for disease development. Symptoms include the development of irregular greasy (at first), brown lesions on main stems and branches. Late pruning (i.e., suckering) can provide entry points for the bacterial disease. Internally, stems will become chocolate brown and mushy. High humidity is necessary for disease development. High nitrogen and lower night temperatures are associated with Pith Necrosis development, where it has been reported around the state this past week. Control begins with cultural practices such as avoiding working in fields with wet foliage, avoiding late pruning, tying when plants are wet, and watching the amount of N applied to plantings. Infected plants can be rouged from field and most often it does not spread to nearby uninfected plants.

Filed Under: Vegetable Crops Tagged With: , ,
July 11, 2023 and

Rutgers Tree Fruit IPM Report for July 14, 2023

Peach:

Oriental Fruit Moth: A biofix point for OFM was set on 4/10 in both northern and southern counties.  All timings for first generation OFM have past. Third generation timings are updated below:

OFM 2nd Generation Timing
Insecticide Type
County/Region Degree Days by  6/30 base 45 Conventional

2100-2200

2350-2450

 Diamide

2025-2150

2375-2450
Gloucester – Southern 1742 1st –about 7/17

2nd –about 7/25

 1st –about 7/16

2nd –about 7/23
Middlesex – Northern 1719 1st – about 7/22

2nd – about 7/29

 1st – about 7/19

2nd – about 7/30

 

Tarnished Plant Bugs; and Other Catfacing Insects: Catfacing insects are active, and activity is increasing with dry weather and summer temperatures. Very little recent fruit feeding has been observed.

Thrips: Flower Thrips have caused slight damage on highly colored ripening fruit, especially in poorly managed ground covers that contain clover or other flowering weeds. The current weather pattern has turned to unfavorable for thrips but they still may cause some damage. Thrips damage appears as “silvering” and usually appears on fruit close to harvest. If populations are high damage can be extensive. Presence of thrips may be scouted for using a beating tray to detect the presence of adults and nymphs in the tree. Flowering weeeds and shrubs on orchard edges may also be scouted by shaking flowers onto a beating tray or a sheet of paper. Delegate or Entrust at the highest labeled rate are the usual recommended materials for thrips in stone fruit. Lannate may be effective in some orchards but has not worked well in recent years. These materials all have short PHI’s and may be applied close to harvest when damage typically appears. See the NJ Commercial Tree Fruit Production Guide for more information. Thrips continue to damage highly colored ripening fruit near harvest.

Japanese Beetle: Japanese beetles have been observed feeding on fruit in southern counties. Adults are attracted to ripening fruit. June bugs also do similar damage. Insecticides that are effective against Japanese beetles and june bugs are products that contain imidacloprid (admire pro and leverage 360); danitol; and sevin.

Apples and Pears:

Diseases: Now that primary scab has ended, the focus turns toward summer diseases such as fruit rots (esp. Bitter rot), and sooty blotch and fly speck. Bitter rot control has been difficult at best in recent years even where management programs have been rigorous. Research has suggested products such as Merivon, Luna Sensation and Inspire Super may be effective, and longtime reliable broad spectrum fungicides such as captan and ziram should provide control. Experience has suggested that the addition of phosphorous acid products such as Prophyt or Rampart to captan sprays may improve control. Observations are that these products improve control of other summer diseases such as sooty blotch and flyspeck, and may help suppress scab infections where present. Bitter Rot symptoms are now appearing in southern counties.

Codling Moth (CM): The first generation codling moth timings have ended. Trap captures continue and decreased in most southern county orchards this week. A biofix was set for CM on April 17th in both northern and southern counties. Second generation timings are updated below. Rimon is not recommended for this and later generations.

Codling Moth Degree Day Timing – Second Generation
Application and Insecticide Type
County Area Biofix Rimon:

75-100DD + 14-17 days later

 

 Intrepid

1150 + 1450 DD

Diamides – Altacor, Voliam mixes: (150-200 DD)

 Madex

1250 DD + every 7-9 days during brood hatch (later if first spray is an IGR)

 Standard Insecticides –  Delegate, Avaunt, OP’s, carbamates, pyrethroids

1250 DD + 1550 DD

 
  DD 1150 1450 1250 1250 1550
Southern April 17 past past past 7/18 7/12 7/12 7/21
Northern  April 17 past past past 7/19 7/13 7/13 7/22

 

Pear: Pear Psylla are still actively laying eggs and nymphs continue to hatch. Options for control include spynosyn products such as Delegate and Entrust, and the neocitinoids (IRAC group 4A). The addition of 0.25-1 gal of summer oil may improve control. Other options include Movento, the IGR’s Esteem and Centaur, and products containing abamectin. Be sure to read and follow the label instructions regarding the addition of penetrants for abamectin products.

Grape: Early blooming native grapes were at 50% bloom on 5/24, therefore we have set the the Grape Berry Moth biofix at 5/24 for southern counties. Typically we would use the bloom date for V. riparia to set the biofix date, however the usual locations we have used in the past did not have viable vines to look at, and it is difficult to scout new locations for V. riparia this year. Since V. riparia typically blooms with early natives we used Concord and Ives to set the biofix. The model works best when growers record their own bloom dates and use the Grape Berry Moth model at NEWA. Applications for GBM using Intrepid or Diamides should be made at 810 DD base 47 (occurred on July 2). Other effective materials can be applied a few days later. The next timing for GBM using Intrepid or Altacor will be at 1620 DD Base 45. This should occur about the end of July. Second generation GBM hatch has started in southern counties.

Japanese Beetle: Japanese beetles have emerged in southern counties. Adults are attracted to leaves and tender shoots. Insecticides that are effective against Japanese beetles are products that contain imidacloprid (admire pro, macho, leverage 360); danitol; and sevin.

Powdery Mildew (PM):  PM symptoms began appearing on berries and rachises around the end of June in several vineyards. Options for eradication or suppression of established infections are limited. Sulfur, Oxidate, potassium bicarbonate products, and mineral oils are most often recommended. Note that sulfur should be used with care and avoided on sulfur sensitive varieties. Sulfur and Captan should never be combined with or used within 2 weeks of oil applications.

Tree Fruit Trap Captures – Southern Counties

STLM TABM-A CM BMSB OFM-A DWB OFM-P TABM-P LPTB PTB
4/15/2023 433 20 1
4/23/2023 423 1 13 8 4
4/30/2023 417 7 15 4 1 0
5/06/2023 9 2 3 1 0 0
5/13/2023 18 2 7 2 3 0 6 6
5/20/2023 5 18 6 0 51 0 13 67
5/27/2023 1 11 4 0 17 0 11 49
6/03/23 3 8 2 1 24 0 13 65
6/10/2023 21 14 5 0 55 0 6 54 0
6/17/2023 10 11 5 0 57 0 8 46 4
6/24/2023 15 5 2 0 57 0 6 47 2
7/1/2023 342 3 0 0 69 0 3 37 6
7/8/2023 463 0 0 0 26 0 0 35 6

Tree Fruit Trap Captures – Northern Counties

STLM TABM-A CM BMSB OFM-A DWB OFM-P TABM-P LPTB PTB
4/8/2023 10
4/15/2023 20 3
4/30/2023 28 11 6
5/06/2023 22 2 19 9
5/13/2023 34 1 3 2 5 0
5/20/2023 31 6 7 1 6 0
5/27/23 16 18 4 1 17 3 11
6/03/23 12 26 2 0 17 2 12
6/10/2023 21 14 5 0 55 0 54
6/17/2023 63 53 2 1 15 1 6
6/24/2023 134 52 3 1 0 11 3 8
7/1/2023

Phenology Table: Based on annual observations made in Gloucester County.

Pest Event or Growth Stage Approximate Date 2023 Observed Date
 Bud Swell (Redhaven)  March 23 +/- 15 Days March 7
1/4″ Green Tip Red Delicious March 31 +/- 13 Days March 27
Pink Peach (Redhaven) April 4 +/- 15 Days March 24
Tight Cluster Red Delicious April 9 +/- 13 Days April 7
Full Bloom Peach (Redhaven) April 9 +/- 14 Days April 4
Pink Apple (Red Delicious) April 14 +/- 12 Days April 11
Full Bloom Apple (Red Delicious) April 22 +/- 11 Days April 16
Petal Fall (Redhaven) April 22 +/- 10 Days April 15
Petal Fall (Red Delicious) April 27 +/- 13 Days  May 3
Shuck Split (Redhaven) April 30 +/- 11 Days April 21
Pit Hardening June 15 +/- 9 Days  June 11

 

 

 

Filed Under: Tree Fruit, Wine Grape
July 11, 2023

North Jersey Wine Grape Twilight Meeting

North Jersey Wine Grape Twilight Meeting

July 18, 2023
5:00 PM – 8:00 PM
610 Perrineville Road
Hightstown, NJ 08520

 

Detailed agenda is forthcoming.
Talks will include disease and pest updates, pH and fertility management.
Pesticide credits are anticipated.

 

RSVP: Please call or E-mail to Kim Crommelin at 908-788-1338 or kfrey@co.hunterdon.nj.us

 

Light fare will be provided. However, please RSVP using above contact information.

 

If any additional assistance is needed, please contact Megan Muehlbauer muehlbauer@njaes.rutgers.edu 

 

 

Filed Under: Fruit, Wine Grape