2013 Financial Assistance Program (FAP) for Producers in Targeted States

Laurie Wolinski, Extension Agent; lgw@udel.edu

FAP funding will be provided to producers in several states, including Delaware and Maryland, who purchase buy-up insurance policies (with some exceptions) for the 2013 crop year with acreage reporting or inventory value reporting dates prior to September 30, 2013.

Policies not eligible for financial assistance include all catastrophic risk protection policies, and any policies or endorsements insured under the Livestock Risk Protection and Livestock Gross Margin plans of insurance.

The Risk Management Agency (RMA) will provide a fixed premium reduction of $225.00 per crop policy for eligible producers. If the total producer-paid premium per crop policy is less than $225.00, the amount of premium reduction will be capped at 100 percent of producer-paid premium for the crop policy. Click the following link for additional information. Check with your Crop Insurance Agent with questions.

http://www.rma.usda.gov/bulletins/managers/2013/mgr-13-008.pdf

Disease Scouting in Full Season Soybeans

Nathan Kleczewski, Extension Specialist – Plant Pathology; nkleczew@udel.edu

Several diseases can be currently found in full season soybeans. I came across the following when scouting grower fields in New Castle County this week. If you have fields that you would like me to check, feel free to contact me at nkleczew@udel.edu or call my office. I’d be more than happy to stop by.

Brown Spot
This is a very common disease in Delaware soybean fields, and rarely does it cause significant yield losses. However, some yield loss may occur during extremely wet growing seasons. Brown spot is caused by the fungus, Septoria glycenes. As the very creative name implies, this pathogen causes brown spots on foliage (Figure 1) and to a lesser extent, stems and pods. Initial symptoms appear first on cotyledons and unifoliate leaves early in the vegetative growth stage and may progress up the plant as it grows. Irregular, brown to red-brown spots can be seen on the upper and lower leaf surfaces. Severely infected leaves turn yellow and fall off the plant. The pathogen is residue-born and some control can be achieved by crop rotation and tillage, although it is rarely economically feasible to manage this disease.

SoybeanBrownSpot

Figure 1. Brown spot on soybean

Downy Mildew
Downy mildew can be currently seen on the upper canopy on soybean plants, and its incidence and severity are very low. The disease is caused by a fungus-like organism called Peronospora manshurica. Symptoms can be seen as small pale green to yellow spots on the upper surface of leaves. If you flip the leaf over you may see a grey to white fuzz on the opposite side of the spots. The pathogen can be borne on either residue or seed. Infection requires long periods of wet weather and cool to moderate temperatures. Downy mildew is rarely yield limiting in soybean, so control is not warranted.

Frogeye Leaf Spot
Frogeye leaf spot was very sparse and only observed at extremely low levels in a single field. The disease can be problematic in some years where environmental conditions favor the disease. The disease is caused by the fungus Cercospora sojina. The pathogen produces tan to brown spots with a Baltimore Ravens purple halo (Figure 2). When inspecting lesions with a hand lens, it may be possible to see black dots with grey/silver-colored spores at the center. If the pathogen infects the pods, seeds can become infected, causing them to turn purple and shrivel. Because the pathogen infects young leaves more readily than older leaves, plants can have a layered appearance, where lesion size on the canopy increases as you move up the plant. Warm wet conditions, especially warm nights with heavy dews, favor disease development. C. sojina overwinters in soybean residue and is spread short distances by wind and rain. Within season management, when warranted, can be achieved with fungicides. However, it is important to note that resistance of C. sojina to group 11 fungicides (strobilurins) has been reported in Arkansas, Kentucky, Illinois, Tennessee, and Missouri. As a result, group 11 fungicides are considered “high risk” fungicides for control of this pathogen. Consequently, group 11 fungicides should be tank mixed with other fungicides that belong to a different fungicide group and are labeled for Frogeye leaf spot. These will most likely be triazole (DMI-group 3) fungicides. Between-season management includes using resistant varieties, crop rotation, tillage where appropriate, and the use of disease-free seed. The 2013 soybean fungicide list and ratings can be found on my blog: http://extension.udel.edu/fieldcropdisease/.

SoybeanFrogeyeLeafspot

Figure 2. Frogeye leaf spot on soybean

Soybean Cyst Nematode
You also may see yellow patches of soybeans in some fields, particularly higher areas of the field or in sandy soils. When you dig up the plants, tiny white or yellow pearls may be observed on roots. These are much smaller than nodules; the inside of a nodule will be red/pink in color when cut open. If you have SCN confirmed in a field, you should strongly consider submitting a soil sample to the diagnostic clinic at the end of the growing season to determine your SCN levels. Remember that symptoms are not always present on plants infected with SCN.

As usual, please contact your local county agent, myself (nkleczew@udel.edu), or submit a sample to the University of Delaware Diagnostic Clinic if you have any potential plant disease issues. Also, try to stay cool out there!

This week’s Field Crop Disease Management Blog topic is Reproduction on Soybean Cyst Nematode on SCN Resistant Varieties.

Agronomic Crop Insects – July 19, 2013

Joanne Whalen, Extension IPM Specialist; jwhalen@udel.edu

Alfalfa
Continue to scout fields on a weekly basis for leafhoppers. In past years, we have also seen an increase in thrips when weather conditions turn hot and drier. So far populations are low but that could change if the recent hot weather continues. Reports from other areas of the country indicate that thrips feeding on the developing leaf tissue can cause the leaves to distort as they emerge. Leaves may also be curled, with a cupped or puckered appearance. Although there are no thresholds for thrips in alfalfa, the following information from other areas of the country may be helpful when considering the need for thrips management: “(a) high populations of bean or onion thrips may cause damage, especially in dryland conditions and (b) if a thrips treatment is contemplated, it is best to cut as soon as possible and treat the regrowth if the infestation persists. Thrips are very difficult to control in alfalfa, so excellent coverage is important and two applications may be required for satisfactory results.”

Soybeans
We continue to see a number of defoliators (grasshoppers, Japanese beetles, bean leaf beetles and green cloverworm) present in full season beans. As full season fields enter the bloom to pod fill stages, remember that the threshold drops to 15% defoliation. When it comes to bean leaf beetle, in areas of the state where we have seen problems in the past, we are seeing an increase in populations. Although first generation populations may not cause economic defoliation, they can be a useful predictor of the second generation. Bean leaf beetle feeding on soybean pods caused by the second generation can lead to significant reductions in seed quality. To help make treatment decisions easier for first and second generation bean leaf beetles, a dynamic Excel spreadsheet has been created by entomologists at Iowa State University that might be helpful in assisting with decisions in our area since no local thresholds are available. Please see the following link for more information –

http://www.extension.iastate.edu/CropNews/2011/0815hodgson.htm .

We are starting to see an increase in stinkbug populations (green and brown) in full season bean fields so be sure to watch for this insect as the earliest maturing fields begin to set pods. Very few brown marmorated stink bugs have been found but we have found them on field edges near woods. Economic damage from stink bugs is most likely to occur during the pod development and pod fill stages. You will need to sample for both adults and nymphs when making a treatment decision. Available thresholds are based on beans that are in the pod development and fill stages. As a general guideline, current thresholds are set at 1 large nymph/adult (either brown or green stink bug) per row foot if using a beat sheet, or, 2.5 per 15 sweeps in narrow-row beans, or 3.5 per 15 sweeps in wide-row beans.

Although the wet weather has kept spider mites populations in check we do find an occasional mite in a field. Be sure that you continue to sample for mites in your routine sampling each week. Early detection and control before populations are exploded is necessary to achieve effective control.

Lastly, although we have not seen soybean aphid problems in recent years be sure to watch for this insect while checking for other insect pests. Reports from the Midwest indicate that aphids were found earlier this year and weather conditions are more favorable for population increases this year.

Calcium Disorders in Apple

Gordon Johnson, Extension Vegetable & Fruit Specialist; gcjohn@udel.edu

Cork spot and bitter pit are disorders in apples that occur when the calcium levels in the fruit are low. Cork spot is seen on the outer surface of the fruit as depressed green spots that enlarge to form corky dark colored areas about ¼ inch deep in the fruit. Bitter pit is found as brown areas of collapsed tissue under the apple skin on the blossom half of the fruit about 1/8 to ¼ inch in size. Bitter pit can occur at harvest but more often develops in storage.

Calcium is important for the development of cell walls and the “cement” between fruit cells. Low calcium in soils is rarely a cause in properly limed orchards. More commonly, it is conditions that impact root activity and that impact the movement of calcium in the soil and in the plant. Dry soils and drought conditions can be a major factor restricting calcium uptake. However, a wet year, such as we are having in 2013, can also affect calcium uptake. Root activity in saturated soils is reduced and cloudy conditions limit transpiration and the movement of calcium in the water flow in the tree. Most of the calcium transport to the fruit occurs in the 4 to 6 week period after bloom. Wet (or dry) conditions during this period will increase the potential for cork spot or bitter pit.

Varieties differ in their susceptibility to bitter pit and cork spot. Some susceptible varieties include York, Red and Golden Delicious, Granny Smith, and Jonathan.

Control of these disorders often requires the use of foliar calcium sprays to the fruit starting after petal fall and continuing through fruit development for 5-8 applications. Other cultural practices that will reduce these disorders include improving orchard drainage, good irrigation management, managing nitrogen (not over-fertilizing), and managing fruit loads with good thinning and pruning practices.

Potato Disease Advisory #12 – July 19, 2013

Nathan Kleczewski, Extension Specialist – Plant Pathology; nkleczew@udel.edu and Phillip Sylvester, Kent Co. Ag Agent; phillip@udel.edu

Location: Art and Keith Wicks Farm, Rt 9, Leipsic, Kent County
Greenrow: May 5

Date

DSV

Total DSV

Accumulated

P-Days

Spray Interval Recommendation

5/23 – 5/27

5

39

5-days

5/27 – 5/30

0

39

10-days

5/30 – 6/6

2

41

251

10-days

6/6 – 6/7

10

51

261

5-days

6/7 – 6/9

10

61

280

5-days

6/9 – 6-13

4

65

314

7-days

6/16 – 6/20

13

78

377

7-days

6/20 – 6/27

6

84

420

7-days

6/28 – 7/4

24

108

477

5-days

7/5 – 7/11

4

112

516

10-days

7/12 – 7/18

11

125

552

10-days

Late Blight
The threshold of 18 DSVs has been exceeded. One hundred and twenty five (125) DSVs have accumulated so far for any potatoes that established green row (approximately 50% emergence) prior to and since May 5. Growers should continue to scout their potato fields and consider applying fungicides preventatively. Any suspect samples can be sent to the UD Plant Diagnostic Lab or dropped off at your local extension office. See the 2013 Commercial Vegetable Production Recommendations-Delaware for recommended fungicides: http://extension.udel.edu/ag/files/2012/03/Potatoes.pdf. The website USABlight tracks tomato and potato late blight across the nation and can be found here: http://usablight.org/. Information on scouting, symptomology, and management can also be found on this website.

Early Blight
The threshold of 300 P-Days has been exceeded. Five hundred and fifty-two (552) P-days have accumulated. A fungicide for early blight control is recommended. Commercial fungicide recommendations can be found in the 2013 Delaware Commercial Vegetable Recommendations Guide at http://extension.udel.edu/ag/files/2012/03/Potatoes.pdf

Phytophthora on Tomatoes and Pink Rot on Potato

Kate Everts, Vegetable Pathologist, University of Delaware and University of Maryland; keverts@umd.edu and Nathan Kleczewski, Extension Specialist – Plant Pathology; nkleczew@udel.edu

It has been a very interesting year for field diseases, and the excessively rainy summer has been very conducive to the development and spread of fungal-like organisms. These include members of the genus Phytophthora. Heavy, persistent rains have allowed these pathogens to cause symptoms on foliage, which is a very rare occurrence. Consequently, we were recently informed that the presumed late blight samples sent from Maryland and Delaware to Cornell for typing, are in fact NOT late blight. The lab in New York confirmed the new diagnoses with ITS sequencing. The sample from tomato in Montgomery Co., MD was the related pathogen Phytophthora capsici. The sample from potato in Kent Co., DE was the related pathogen Phytophthora nicotianae. Both of these pathogens are also important and damaging diseases.

Phytophthora capsisi causes crown and fruit rot on tomato. It is uncommon for P. capsici to cause lesions on tomato leaves, here in Maryland. More typically we see crown and fruit symptoms. To manage fruit rot, apply mefenoxam (Ridomil Gold™ or Ultra Flourish™) as a soil surface application under the vines 4 to 8 weeks before harvest. Another approach is to apply mefenoxam + chlorothalonil, Ridomil Gold Copper™, Gavel™ or Tanos™, when the crown fruit are one-third their final size. Repeat at 14 day intervals up to a total of 3 times.

Likewise it is unusual to see P. nicotianae on potato leaves. Leak is usually associated with tubers that have been bruised during harvest in hot weather. Management is to apply fungicides in a 6 – 8inch band directly over the seed piece during planting. Fungicides which are effective are Platinum Ridomil Gold ™, Presidio™, Ridomil Gold™, Ultra Flourish™, or Ranman™. An alternative method is to apply one of the following at flowering and 14 days later (in an high gallonage as possible, minimum of 5 gpa aerial application); Ridomil Gold Bravo™, Ridomil Gold Copper™, or Ridomil Gold MZ™. See the Commercial Vegetable Recommendation Guide for more information.

The wet weather has brought out the Phytophthora species on other crops as well. In addition to P. capsici on tomato foliage, we have seen lesions on watermelon leaves. These lesions appeared similar to the (more typical) lesions on pumpkin leaves.

PnicotianaeLeaf2 PnicotianaeLeaf1

 

Phytophthora nicotianae symptoms on potato

Excess Water Problems in Potato

Gordon Johnson, Extension Vegetable & Fruit Specialist; gcjohn@udel.edu

Wet seasons are always a challenge for potato growers. Several disorders are seen on potatoes when soils stay saturated.

Blackheart is often a problem in potatoes in wet years. This is a disorder related to low oxygen conditions. Heavy rainfall, especially on our heavier silt loam soils, sets up conditions for blackheart to develop. In soils that are flooded or that stay saturated for long periods of time, oxygen diffusion into potato tubers is restricted (oxygen diffusion is much slower through water than soil air spaces). Lack of oxygen to the tuber interior causes interior tissue to die and ultimately turn brown, purple, or black. When dug, tubers may appear normal on the outside, but when cut reveal the dead areas. This makes grading very difficult. With each truckload coming into the packing shed, a sample of tubers must be cut open and if a significant percentage show blackheart, the load is rejected.

Blackheart can also occur when soils are compacted, restricting air movement; when soils are hot and tubers are respiring heavily, using up more oxygen than can diffuse through the soil; and in storage or shipping when piled too high or stacked too closely for long time periods, again restricting oxygen. Managing low oxygen blackheart in the field requires attention to drainage, forming high loose ridges around tubers (avoid cultivating and ridging when soils are wet), managing field traffic to limit compaction, and harvesting in a timely manner, targeting fields with higher potential for blackheart to be dug first. Low areas in fields may have to be examined (samples cut open to see the percent of blackheart) and passed over during harvest.

Another wet weather disorder in potatoes is raised or enlarged lenticels. Lenticels are small openings in the tuber surface that allow for gas exchange necessary for tuber respiration. Enlarged lenticels occur where there is excessive soil moisture in wet seasons. This is a common problem in heavier soils, field bottoms, and compacted areas. In wet conditions, there is a proliferation of cells that form the lenticel pore making the pore larger. This cell proliferation will cause the potato to have raised white spots throughout the tuber surface. The area immediately surrounding the lenticels may also rise up, forming a “halo” around the lenticels. This is called halo disorder. Potatoes with raised lenticels may be subject to abrasion damage in packing. Raised lenticels can heal by forming suberin. However, the suberized closing layer can be ruptured when the cells beneath it proliferate under unfavorable conditions. Ruptured lenticel cells can be a point of entry and infection by bacterial soft rot organisms.

PotatoRaisedLenticels

Raised lenticels on a potato tuber due to wet soil conditions.

Vegetable Crop Insects – July 19, 2013

Joanne Whalen, Extension IPM Specialist; jwhalen@udel.edu

Kudzu Bug on Succulent Beans
As indicated in past newsletters, initial findings from host preference studies from Georgia indicate that Kudzu bug does not prefer non-soybean beans, but will occur on them. We have sent samples of 3 lima bean varieties (C-elite Select, Cypress and Concentrated Fordhook) to the Georgia program to be evaluated so we will have more information as soon as it is available. In the one pole lima bean where the first adults were detected, the numbers of adults have dwindled and a few egg masses where found but no nymphs hatched. As a reminder, it is the nymph that is important in regards to treatment in soybeans once fields reach flowering and the pod development stage. Also, this insect is a slow feeder that will gradually drawing down plant vigor therefore it gives us plenty of time to sample fields and react with a treatment if needed. In the meantime, as I have indicated in past newsletters, you will want to scout succulent beans to see if this trend is true in our area. We may have to use the information developed for soybeans this season to help us make management decisions in succulent beans if the need arises. We will keep you posted of any new finds as well as new management information as it is developed.

Lima Beans
With the wet weather, spider mites problems have not occurred like last year but we do find an occasional mite in a field. Be sure that you continue to sample for mites in your routine sampling each week. Early detection and control before populations are exploded is necessary to achieve effective control. We are starting to see an increase in stinkbug and plant bug populations. As soon as pin pods are present, be sure to watch carefully for plant bug and stinkbug adults and nymphs. As a general guideline, treatment should be considered if you find 15 adults and/or nymphs per 50 sweeps.

Melons
Continue to scout all melons for aphids, cucumber beetles, and spider mites. Although aphid populations still remain low in most fields, we have had reports of localized infestations. At this time of year, early detection is critical since populations can quickly explode. It is also the time of year to watch for beet armyworm, yellow striped armyworm, cabbage loopers and cucumber beetle adults feeding on the rinds of watermelons. If beet armyworm is in the mix, it is important to select a material that is effective on this insect (refer to the Commercial Vegetable Recommendations) – the pyrethroids do not provide effective control.

Peppers
Depending on local corn borer trap catches, sprays should be applied on a 7 to10-day schedule once pepper fruit is ¼ – ½ inch in diameter. Be sure to check local moth catches in your area by calling the Crop Pest Hotline (instate – 800 345-7544; out of state- 302 – 831-8851) or visit our website at http://agdev.anr.udel.edu/trap/trap.php. At this time, you will also need to consider a treatment for pepper maggot. Be sure to also watch carefully for beet armyworm larvae since they can quickly defoliate plants. In addition, be sure to use a material that provides beet armyworm control – the pyrethroids will not control this insect.

Snap Beans
As corn borer and corn earworm populations start to increase again, you will need to consider treatments for both insect pests. Sprays are needed at the bud and pin stages on processing beans for corn borer control. As earworm trap catches increase, an earworm spray may also be needed at the pin stage. You will need to check our website for the most recent trap catches to help decide on the spray interval between the pin stage and harvest for processing snap beans. Once pin pods are present on fresh market snap beans, a 7 to 10-day schedule should be maintained for corn borer and corn earworm control.
http://agdev.anr.udel.edu/trap/trap.php

http://extension.udel.edu/ag/insect-management/insect-trapping-program/ecb-and-cew-moth-catch-thresholds-for-processing-snap-beans/

Sweet Corn
Be sure to sample all fields from the whorl through pre-tassel stage for corn borers, corn earworms and fall armyworm. We are starting to see an increase in whorl infestations of fall armyworm. A treatment should be considered when 12-15% of the plants are infested. Since fall armyworm feeds deep in the whorls, sprays should be directed into the whorls and multiple applications are often needed to achieve control. The first silk sprays will be needed for corn earworm as soon as ear shanks are visible. Be sure to check both blacklight and pheromone trap catches for silk spray schedules since the spray schedules can quickly change. Trap catches are generally updated on Tuesday and Friday mornings You can also call the Crop Pest Hotline (in state: 800-345-7544; out of state: 302-831-8851). http://agdev.anr.udel.edu/trap/trap.php

http://extension.udel.edu/ag/insect-management/insect-trapping-program/action-thresholds-for-silk-stage-sweet-corn/)