Posts Tagged ‘19:10’

WCU Volume 19, Issue 10 – May 27, 2011

Friday, May 27th, 2011

PDF Version of WCU 19:10 – May 27, 2011

In this issue:

Vegetables
Vegetable Crop Insects
Potato Disease Advisory #3 – May 26, 2011
Fasciation in Vegetables and Fruits
MELCAST for Watermelons

Fruit
Update on Brown Marmorated Stink Bugs in Orchards
Spittle Bugs Common in Strawberry this Year

Agronomic Crops
Agronomic Crop Insects
Small Grain Disease Update
Grain Marketing Highlights

Weather

 

Grain Marketing Highlights – May 27, 2011

Friday, May 27th, 2011

Carl German, Extension Crops Marketing Specialist; clgerman@udel.edu

Commodity Markets Turn Higher
Planting delays in the Eastern Corn Belt and the Dakotas have raised serious concerns as to whether U.S. farmers will reach their planting goals this year. After ignoring Monday afternoon’s Weekly Crop Progress report, that showed U.S. corn plantings to be 79% complete (8 points behind the five year average), commodity markets turned higher Wednesday, with higher opening calls for Thursday’s trading session. A part of the reason for the current surge in corn, soybean, and wheat prices has to do with the uncertainty in determining just how many acres the U.S. will actually get planted to corn and soybeans this season. The March 31 Planting Intentions report called for 92.2 million acres to be planted to corn and 76.6 million acres to be planted to soybeans. Some are suggesting that time is running out. Saturated fields in places like North Dakota, Indiana, and Ohio are not likely to get planted in a timely fashion. Timely fashion, for crop insurance purposes, in the Eastern Corn Belt translates to June 5. As of May 22, 14.2 million acres remained to be planted in the U.S. A large portion of those remaining acres are either flooded, and/or saturated.

USDA Export Sales Report 05/26
Pre-report estimates for weekly export sales of soybeans ranged from 5.5 to 11.9 million bushels. The weekly report showed total old-crop export sales of 6 million bushels, above the 2 million bushels needed this week to stay on pace with USDA’s demand projection of 1.55 billion bushels. Total shipments of 15.1 million bushels were above the 12.7 million bushels needed this week. This report is considered bullish.

Pre-report estimates had weekly corn export sales 19.7 to 35.4 million bushels. The weekly report showed total export sales (old-crop and new-crop) of 30.5 million bushels, with old-crop sales of 28.6 million bushels, well above the 14.7 million bushels needed this week to stay on pace with USDA’s demand projection of 1.9 billion bushels. Total shipments of 37.5 million bushels were below the 42.4 million bushels needed this week. This report is considered neutral.

Pre-report estimates for export sales of wheat ranged between 14.7 to 25.7 million bushels. The weekly report showed total export sales (old-crop and new-crop) of 15.9 million bushels, with old-crop sales of 1 million bushels bringing year-to-date sales to 1.3 billion bushels, above USDA’s 1.275 billion bushel demand projection. Shipments of 28.9 million bushels were well below the 62.4 million bushels needed this week. This report is considered bearish. Next week’s report will be the last of the 2010-2011 marketing year for wheat with 96 million bushels needed in shipments to reach USDA’s target.

Market Strategy
The window of pricing opportunity presented by the planting scenario above is likely to be short lived. It will not take long before traders consider planting delays already factored into commodity prices. It is within the realm of reason to expect Western Corn Belt producers to pick up some of the slack, planting more acres than their March intentions. These markets are also being heavily influenced by outside market forces. An economic crisis still prevails across the globe with large scale economic problems recently capturing headlines in Spain, Italy, Greece, and the United States. Further, continuing reports of demand shifts occurring due to the price level being bid by commodities has become a recurring theme. If a weather market doesn’t develop this summer, we could be seeing the highs for this growing season being made between now and early June. Therefore, it might be wise to consider scaling up on corn, soybean, and wheat sales as prices rise. Currently, on the open (5/26/11) Dec corn futures are trading at $6.76; Nov ‘11 soybean futures at $13.73; with July SRW wheat futures at $8.16 per bushel.

 

Small Grain Disease Update – May 27, 2011

Friday, May 27th, 2011

Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu

Barley
The most prevalent diseases that can still be seen in areas where the barley has not returned yet are the spot blotch form of net blotch and powdery mildew. After checking the barley varieties today near Sandtown in western Kent County I don’t believe that net blotch will be affecting yields, but powdery mildew on unsprayed ‘Thoroughbred’ will reduce yields if the flag leaf is infected. There is some scab infected barley in Kent County.

Wheat
The wheat in the Kent County variety trial has tan spot moving in rapidly on some varieties. Most of the varieties are in the watery ripe stage of development and will not likely be adversely affected. Leaf rust was easily seen on a public variety ‘Rumor’. Powdery mildew in general was low in most varieties but was in the upper canopy on SS8302, Milton, Bravo, and USG3770. There is a low level of scab in the trial as well. If scab is going to appear it should be evident now or very soon depending on location. Low levels of scab (less than 1% of the heads infected and most of the infected heads were only partially infected) were present in 8 out of 45 varieties (around 18%).There is some sort of physiological spotting that could look like a disease but is probably a resistance reaction by the variety in response to a fungal infection. This spotting was evident on the following varieties at this Sandtown location: Merl, Sunburst,USG3665, USG3409, USG3251, and Grow Mark FS627.

 

Agronomic Crop Insects – May 27, 2011

Friday, May 27th, 2011

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

Alfalfa
Potato leafhoppers are now present in fields so be sure to sample on a weekly basis after the first cutting. Once plants are yellow, yield loss has already occurred. The treatment thresholds are 20 per 100 sweeps on alfalfa 3 inches or less in height, 50 per 100 sweeps in 4-6 inch tall alfalfa and 100 per 100 sweeps in 7-11 inch tall alfalfa.

Field Corn
True armyworms can now be found in corn fields. As small grain dries down, be sure to watch for armyworms moving out of small grain and into adjacent corn fields. You should also scout corn for armyworms in fields that were planted into a small grain cover. Remember, worms must be less than 1 inch long to achieve effective control. The treatment threshold for armyworms in corn is 25% infested plants with larvae less than one-inch long. Large larvae feeding deep in the whorls will be difficult to control.

Small Grains
As small grains dry down, be sure to watch for head clipping from armyworm and sawfly. In fields that did not receive an insecticide spray, we continue to find economic levels of armyworms. On barley, significant head clipping from armyworms can quickly occur. As a general guideline, the threshold for armyworms in barely is one per foot of row and for wheat one-two per foot of row. Before making an application of an insecticide, be sure to check all labels for the number of days between last application and harvest.

 

Spittle Bugs Common in Strawberry this Year

Friday, May 27th, 2011

Jerry Brust, IPM Vegetable Specialist, University of Maryland; jbrust@umd.edu

Many strawberry growers have seen the meadow spittlebug (Philaenus spumarius) in their strawberries this year. Some of these growers include high tunnel growers who have never seen spittle bugs before in their high tunnel strawberries. The spittlebug is an annoying pest on strawberries that under extremely high numbers can stunt plants and reduce berry size. But they are more of a nuisance especially to u-pick growers as the pickers object to being wetted by the insect excretion (the spittle, even though it is harmless).

Spittlebugs can be recognized by the white masses of foam found on leaves, petioles, and stems of plants (Fig. 1). The yellow-green nymphs produce this covering to protect themselves from predators and desiccation. Initially the nymphs feed at the base of the plants, but later move up to more tender foliage. Feeding may cause leaves to become wrinkled and dark-green. Although fruit may be stunted under heavy spittle bug populations, yield loss rarely occurs. High spittlebug populations are often correlated with weedy (including legume cover crops like clover) fields, so proper weed control is important. Nymphs feed for five to eight weeks before entering the adult stage. Newly emerged adults (called froghoppers) are bright green and darken over time to a dull brown. They are very active and readily jump when disturbed. Adults are present on foliage May through November but do not produce any spittle. Adults lay white to cream-colored eggs in the stems and leaves of plants from July through October. These eggs will overwinter and hatch next spring. There is one generation per year in Maryland.

Treatment is rarely necessary for spittlebugs, but u-pick growers need to keep populations to one spittle mass per square foot through prebloom to placate customers. It will be necessary to spread plants and inspect the crowns as well as leaves and stems. Control is considered at one spittlebug per square foot for u-pick operations and 5-6 per square foot (a high population) for everyone else. Aphid control products such as Assail, Thionex, Nuprid, etc. will control spittlebugs too.

Figure 1. Spittle on stems of plants produced by spittle bugs

 

Update on Brown Marmorated Stink Bugs in Orchards

Friday, May 27th, 2011

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

Tracy Leskey (USDA/ARS) provided the following report: “It appears that the beginning of Brown Marmorated Stink Bug (BMSB) immigration and dispersal into commercial orchards has begun in earnest in both WV and MD. Crews out scouting reported large numbers of BMSB in managed peach trees. Not surprisingly, bugs were most dense in the peripheral zone of the plots bordering wild habitat, but not necessarily anywhere near structures. Estimates of bug density were in the vicinity of 3 bugs per tree in border rows, and feeding injury was very fresh but clearly evident.”

See the article titled ‘Brown Marmorated Stink Bugs Damaging Peaches and Apples in WV, NJ, MD and VA’ in WCU 19:9 for more information and photos of damaged fruit.

 

MELCAST for Watermelon

Friday, May 27th, 2011

Kate Everts, Vegetable Pathologist, University of Delaware and University of Maryland; keverts@umd.edu

The weather based forecasting program MELCAST on watermelon began on Wednesday (May 25). MELCAST is a weather-based spray scheduling program for anthracnose and gummy stem blight of watermelon. If you received a report in 2010, you should have automatically received the first report. If your email or Fax number has changed, please call us. If you did not receive a report and would like to, please call Jeri Cook at (410) 742-8788 and give us your name and Fax number or e-mail address. MELCAST also is available online – bookmark the site http://mdvegdisease.umd.edu/. Click on the watermelon picture.

To use MELCAST for watermelons, determine which site is closest to your farm field. Apply the first fungicide spray when your watermelon vines meet within the row. Additional sprays should be applied using MELCAST. Accumulate EFI (environmental favorability index) values beginning the day after your first fungicide spray. Apply a fungicide spray when 30 EFI values have accumulated by the weather station nearest your fields. Add 2 points for each overhead irrigation that is applied. After a fungicide is applied, reset your counter to 0 and start over. If a spray has not been applied in 14 days, apply a fungicide, reset the counter to 0 and start over. Please call if you have any questions on how to use MELCAST on your watermelon crop (Kate Everts at 410-742-8789).

Because there is widespread resistance to strobiluron (group 11) fungicides in Maryland and Delaware, growers should alternate one of the following with chlorothalonil (Bravo, etc.); a tebuconazole product (such as Folicur), Inspire Super, or Switch. Resistance to Pristine has been recorded in many watermelon fields in the southern U.S. We have not found resistance to Pristine here in Delaware or Maryland, yet. However, Pristine should be used with great caution; always tank mixed with chlorothalonil; and alternated with a fungicide that has a different mode-of-action. If a serious disease outbreak occurs in your field, return to a weekly spray schedule.

 

Fasciation in Vegetables and Fruits

Friday, May 27th, 2011

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

In recent visits to watermelon fields in Delaware for pollination and fruit set surveys, we found a high number of pollenizer plants in one field that had one or more fasciated stems.

Fasciated stems are ones that are flattened and look like several stems have been fused together. They may be fan shaped in appearance. We also commonly see fasciation in strawberry fruits which develop a “cockscomb” appearance. Fasciation occurs when a growing point changes from a round dome of cells into a crescent shape. Subsequent growth produces a flat stem, flower, or fruit. In some cases fasciation is the result of several embryonic growing points fusing together, with the same flattened or fan-like appearance.

Although the causes of fasciation are not well understood, it is most likely because of a hormonal imbalance. Use of herbicides that are hormone analogs (such as those in the growth regulator or 2,4-D family) can often cause fasciation.

Fasciation can also be due to a random genetic mutation. In some cases, these mutations have been taken advantage of to produce new plants (many ornamentals) that then are propagated vegetatively to keep the fasciated appearance.

Fasciation can also be induced by one or more environmental factors, most commonly cold damage in the spring. Fasciation may also be induced by physical damage to the growing point.

Plant pests may also cause fasciation. Pathogens (bacteria, fungi, virus), insects, and mites, and insects may damage growing points or cause plants to produce excess hormones that will result in fascinated plants.

Go to the Purdue Plant and Pest Diagnostic Laboratory site for a picture of a fascinated sweet potato stem: http://www.ppdl.purdue.edu/PPDL/images/fasciatedsweetpot2.jpg.

 

Potato Disease Advisory #3 – May 26, 2011

Friday, May 27th, 2011

Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu

Late Blight Advisory
Location: Art and Keith Wicks Farm, Rt 9, Little Creek, Kent County.
Greenrow: May 3

Date DSV Total DSV Spray Interval Recommendation
5/3–5/12 0 0 none
5/13-5/15 11 11 none
5/15-5/16 3 14 none
5/16–5/19 19 33 5-days
5/19-5/21 5 38 5-days
5/21-5/23 12 50 5-days
5/23-5/24 2 52 5-days
5/24-5/25 0 52 5-days

 

The threshold of 18 DSVs has been exceeded. The weather since last Friday has been very favorable for late blight if the fungus was present. Fifty-two (52) DSVs have accumulated so far for any potatoes that established green row (approximately 50% emergence) prior to and since May 3. Spraying as soon as possible with a protectant fungicide would be advised.

The summer-like weather we are having now with the high temperatures will reduce the risk and slow any development of late blight for the duration of the hot weather. Be sure to scout fields after that very conducive period for infection.

Next week I will start including P-day values for predicting early blight. We have only accumulated 160 so far. The early blight threshold is 300 P-days which indicates when conditions have become favorable for early blight infections to occur.

 

Vegetable Crop Insects – May 27, 2011

Friday, May 27th, 2011

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

Cucumbers
All fields should be scouted for cucumber beetles and aphids. Fresh market cucumbers are susceptible to bacterial wilt, so treatments should be applied before beetles feed extensively on cotyledons and first true leaves. Although pickling cucumbers have a tolerance to wilt, a treatment may still be needed for machine-harvested pickling cucumbers when 5% of plants are infested with beetles and/or plants are showing fresh feeding injury. A treatment should be applied for aphids if 10 to 20 percent of the plants are infested with aphids with 5 or more aphids per leaf.

Melons
Continue to scout all melons for aphids, cucumber beetles, and spider mites. The treatment threshold for aphids is 20% infested plants with at least 5 aphids per leaf. Be sure to also watch for beneficials. The threshold for mites is 20-30% infested crowns with 1-2 mites per leaf. We have seen an increase in cucumber beetle activity, especially in cantaloupe fields. Since beetles can continue to re-infest fields as well as hide under the plastic, multiple applications are often needed.

Peppers
Continue to sample for thrips. We are hearing reports of an increase in thrips activity in crops grown in southern states. You should also continue to sample for corn borers and watch carefully for egg masses. Before fruit is present these young corn borer larvae can infest stems and petioles. Be sure to also check local moth catches in your area by calling the Crop Pest Hotline (instate: 800-345-7544; out of state: 302-831-8851) or visiting our website at http://ag.udel.edu/extension/IPM/traps/latestblt.html.

Potatoes
Fields should be scouted for Colorado potato beetle (CPB), corn borers (ECB) and leafhoppers. Adult CPB as well as the first small larvae can now be found in fields not treated at planting. A treatment should be considered for adults when you find 25 beetles per 50 plants and defoliation has reached the 10% level. Once larvae are detected, the threshold is 4 small larvae per plant or 1.5 large larvae per plant. As a general guideline, controls should be applied for leafhoppers if you find ½ to one adult per sweep and/or one nymph per every 10 leaves.

Snap Beans
Continue to sample all seedling stage fields for leafhopper and thrips activity. The thrips threshold is 5-6 per leaflet and the leafhopper threshold is 5 per sweep. If both insects are present, the threshold for each should be reduced by 1/3. Once corn borer catches reach 2 per night, fresh market and processing snap beans in the bud to pin stages should be sprayed for corn borer. Sprays will be needed at the bud and pin stages on processing beans. Once pins are present on fresh market snap beans and corn borer trap catches are above 2 per night, a 7 to 10-day schedule should be maintained for corn borer control. You can call the Crop Pest Hotline for the most recent trap catches (instate: 800-345-7544; out of state: 302-831-8851) or visit our website at http://ag.udel.edu/extension/IPM/traps/latestblt.html.

Sweet Corn
Continue to sample seedling stage fields for cutworms and flea beetles. You should also sample all whorl stage corn for corn borers. A treatment should be applied if 15% of the plants are infested. The first silk sprays will be needed for corn earworm as soon as ear shanks are visible. Be sure to check trap catches since the spray schedules can quickly change. You can call the Crop Pest Hotline for the most recent trap catches (instate: 800-345-7544; out of state: 302-831-8851) or visit our website at http://ag.udel.edu/extension/IPM/traps/latestblt.html