Posts Tagged ‘18:2’

WCU Volume 18, Issue 2 – March 26, 2010

Thursday, March 25th, 2010

PDF Version of WCU 18:2 – March 26, 2010

In this issue:

Vegetables
Producing Quality Seedless Watermelon Transplants
2010 Fungicide Update for Vegetables
Fungicide Guide for Managing Resistance of Fungi on Vegetable Crops Available Online
Information on Potato and Tomato Late Blight Management
Winter Temperature Index for Predicting Stewart’s Wilt in Delaware Sweet Corn 2000-2010

Agronomic Crops
Agronomic Crop Disease Update
Italian Ryegrass Control for No-Till Corn
Horseweed is Getting Harder to Control
Ignite 280 – Where is the Fit for Soybeans?
Weed Control in Forages
Grain Marketing Highlights

Announcements
Local Farmers Wanted for Western Sussex Farmer’s Market
Invitation to Join the Fruit and Vegetable Growers Association of Delaware
New Castle County Agronomic Grower Meeting and 3rd Annual Dinner

Weather

Grain Marketing Highlights

Thursday, March 25th, 2010

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

2010 Preliminary Crop Production Forecasts
An important date lies just ahead for the grain trade. March 31 marks the release of USDA’s survey based Prospective Plantings and the 1st quarter Grain Stocks in All Positions reports. These reports are important because they will set the stage for commodity trading going into the spring and summer months, coinciding with the time period that we generally experience seasonal rallies in the corn and soybean markets. The looming questions going into the reports are the number of 2010 corn and soybean acres famers say they intend to plant and whether the stocks report suggests lower or higher ending stocks for the ‘09/‘10 marketing year? The size of the production estimates and the amount of stocks on hand will help to determine the extent of the expected seasonal rally. Another factor likely to determine the extent of a seasonal rally is the weather. Although still early, saturated soils throughout the Corn Belt may prove to be reason to remain cautiously optimistic concerning commodity prices this spring and early summer. The nation’s farmers are not expected to risk delayed planting for corn this year considering the high moisture problems that were prevalent in the 2009 U.S. corn harvest.

Informa Economics estimates 2010 U.S. corn acreage at 88.427 million acres; soybean acreage at 78.629 million acres; and all U.S. wheat acreage at 53.655 million acres ahead of the March 31 report. Allendale Inc. estimates planted corn acres at 90.2 million acres; soybean plantings at 79.1 million acres; and all wheat acres at 53.4 million acres. The markets will settle on trading USDA’S projections that will be released next Wednesday.

Market Strategy
Currently, initial support for May corn futures lies at $3.61. If May corn closes below that level then the next level of support is at $3.51. Support for May soybeans is at $9.58. Both markets are trading at or below support levels this morning. If broken, then we are likely to see nearby corn and soybean prices moving lower in the near term.

New crop Dec ‘10 corn futures are currently trading at $3.90 per bushel (12 cents lower); Nov ‘10 soybean futures at $9.28 (11 cents lower); with July ‘10 SRW wheat futures at $4.86 per bushel (13 cents lower than last week’s recorded prices). The lower prices are attributed to the harvest of the Southern Hemisphere corn and soybean crops; harvest progress in the Northern tier of the U.S. Corn Belt; and a drier 7 to 10 day forecast for the Midwest. For technical assistance on making grain marketing decisions contact Carl L. German, Extension Crops Marketing Specialist.

Weed Control in Forages

Thursday, March 25th, 2010

Quintin Johnson, Extension Associate – Weed Science; quintin@udel.edu and Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

If you have not done so yet, be sure to examine your hay, pasture, and alfalfa fields for weed infestations. Earlier applications are much more effective than later, as weeds get larger and start to produce seeds. For grass hayfields or pastures, weed control options include dicamba (Banvel or Clarity), 2,4-D, Overdrive, Crossbow, or Cimarron Max. Metsulfuron (active ingredient in Cimarron Max and Cimarron Ultra) and Crossbow provide residual control, while the other products do not. Be sure to read the label and follow all precautions concerning grazing and haying restrictions as well as overseeding and re-seeding restrictions. Remember that grasses seeded last fall should be tillering, actively growing, and mowed at least once before applications of dicamba or 2,4-D can be made.

Ignite 280 – Where is the Fit for Soybeans?

Thursday, March 25th, 2010

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

Ignite 280 (glufosinate) is now labeled for burndown and can be used postemergence in Liberty Link soybeans. For non-Liberty Link soybeans it can be used as the burndown, particularly in fields with heavy horseweed pressure, and in situations where 2,4-D is not an option for horseweed control. While Ignite 280 is very effective on horseweed (marestail), it is not effective on larger grasses or some winter annual species such as field pansy. As a result, it will often need to be part of a tank mix combination for burndown weed control, typically with a product that will control field pansy.

In Liberty Link soybeans, I see a better fit for Ignite 280 as a herbicide to control weeds four weeks after planting, rather than as a pre-plant herbicide. This does not mean you should consider Ignite 280 applied postemergence in soybeans as a viable option for horseweed control. Rather, always start with a clean field (everything dead at planting time), include a solid residual herbicide with your burndown, and a timely postemergence application of Ignite 280 about 4 weeks after planting.

● Starting clean often means your burndown application is made 4 weeks preplant so you can use an effective rate of 2,4-D for resistant marestail control

● A solid residual program should include a grass herbicide such as Dual, Outlook, or Micro-Tech plus a broadleaf herbicide since Ignite is not effective on large grasses. The residual herbicide will control grasses, or at least result in smaller more susceptible grasses at time of postemergence application.

● Postemergence applications need to be made timely, approximately 4 weeks after planting. While Ignite 280 is a broad-spectrum herbicide it is strictly a contact herbicide. It is difficult to get good coverage with larger weeds.

A couple of other items to consider with Ignite 280. As noted, good coverage is important for effective control, and this usually means effective spray volumes. Using low spray volumes may result in reduced levels of control. The label requires a spray volume of 15 gal/A, but even with that volume the spray boom needs to be well calibrated and provide a uniform distribution of medium sized spray droplets. Also, Ignite 280 requires the plant to have active photosynthesis at time of application for maximum effectiveness. Applications should not be made within 2 hours of sunset to ensure active photosynthesis.

Horseweed is Getting Harder to Control

Thursday, March 25th, 2010

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

We confirmed a population of horseweed (or marestail) in Delaware that is resistant to glyphosate and ALS-inhibiting herbicide. This field had been treated with Finesse and Canopy EX and glyphosate and the horseweed was not controlled. We collected seed from this field and tested it in the greenhouse. This is the first confirmation of multiple resistance for horseweed in the Mid-Atlantic states. Glyphosate will not control this biotype, but neither will chlorimuron or FirstRate. Chlorimuron is the active ingredient in Classic, Canopy SG, Canopy EX, Synchrony, Envive, and Valor XLT. Controlling these populations will require 2,4-D (at 1 qt/A for consistent control), Ignite 280, or Kixor (but Kixor needs to be applied at least 30 days prior to planting in coarse-textured soils). The most cost-effective approach will be use of 2,4-D applied at 1 qt/A at least 30 days prior to planting. Delaying the 2,4-D applications until closer to planting will result in lower rates of 2,4-D being applied, less effective horseweed control, and more situations that are not appropriate for 2,4-D because of emergence of nearby crops and vegetables.

NOTE: There are many circumstances where 2,4-D is not an option due to susceptible plants or greenhouses in the area. Be sure to know the surrounding area before you treat a field with 2,4-D to be sure it is an appropriate treatment for the area.

Italian Ryegrass Control for No-Till Corn

Thursday, March 25th, 2010

Mark VanGessel, Extension Weed Specialist; mjv@udel.edu

Italian ryegrass is the same as annual ryegrass. The weed we struggle to control in wheat and barley is the same plant that is sometimes used as a cover crop. The same characteristics that make it a good cover crop are the same attributes that make it a pesky weed. Furthermore, it is the same species that has developed resistance to glyphosate and a number of other common herbicides.

Whether it was planted as a cover crop or there are scattered plants throughout the field, annual ryegrass can be troublesome to control in no-till corn. A trial for annual ryegrass control was conducted in 2009 at UD’s Research and Education Center. Treatments included glyphosate or Gramoxone Inteon and they were either applied alone, with atrazine, with Bicep II Magnum, with Resolve, or with Bicep II Magnum plus Resolve. Glyphosate control was about 85% control, but when tankmixed with atrazine or Bicep, control was reduced to 70 to 75% control. The addition of 1 oz of Resolve to glyphosate plus atrazine or glyphosate plus Bicep II Magnum increased annual ryegrass control to over 90%. The three-way mix of Gramoxone Inteon, Bicep II Magnum, and Resolve also provided over 90% control, and this was higher than any other combination with Gramoxone Inteon. Annual ryegrass (or Italian ryegrass) is difficult to control. The addition of Resolve improved ryegrass control. In our trial, corn planting was delayed at least 2 weeks after herbicide application and no injury from Resolve was observed.

Annual ryegrass should be sprayed early, 4 to 6 inches tall. Larger plants are more difficult to control and increase the likelihood of needing two herbicide applications to kill it.

Agronomic Crop Disease Update

Thursday, March 25th, 2010

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

Wheat
It has been a tough year for wheat production. The wet fall delayed planting, then large areas have been inundated with water for long periods of time and there has been grazing by geese. Areas of the state where wheat has survived but under very wet conditions may be at risk from Pythium root rot if wet conditions persist. The other threat, as if there wasn’t enough trouble for wheat, is from the fungal transmitted soilborne viruses, wheat soilborne mosaic virus and wheat spindle streak mosaic virus (WSSMV). Wet soils in the fall following planting can result in severe infections of wheat soilborne mosaic virus that appear as irregular stunted areas in low areas of the field. Mild stunting and yellow green mottling, dashes and streaks on the leaves are diagnostic for WSSMV. There are no controls for either disease for the present crop. Resistant varieties for both diseases are available.

Soybean Cyst Nematode Survey
I am waiting on the results of the last two soil samples before presenting the results of the Delaware Soybean Board sponsored survey for SCN in Delaware. The results so far have confirmed a shift of the race composition in Delaware soybean fields and the nasty nematode has not gone away.

Winter Temperature Index for Predicting Stewart’s Wilt in Delaware Sweet Corn 2000-2010

Thursday, March 25th, 2010

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

Prediction for 2010
Georgetown: 101.7 = Severe – Avg. monthly temp (Dec, Jan, Feb) = 33.9 °F
Newark: 97.5 = Intermediate – Avg. monthly temp = 32.5 °F

Control Strategies
For processing and fresh market growers this means that if you are planting susceptible or moderately susceptible hybrids that flea beetle control is very important. A number of strategies are available including seed treatments, granular insecticides at planting and/or foliar applied insecticides after emergence. For foliar applied insecticides treat susceptible cultivars at spike stage when 5% of the plants are infested. See the 2010 Delaware Commercial Vegetable Production Recommendations for control suggestions.

Average monthly temperatures in °F at Georgetown, DE. REC. 2000-2010

2009-2010 2008-2009 2007-2008 2006-2007 2005-2006 2004-2005 2003-2004 2002-2003 2001-2002 2000-2001
December 37.9 41.8 39.7 43.5 36.2 38.9 38.6 36.7 43.2 31.2
January 32.7 31.0 36.8 39.7 43.0 34.9 29.5 28.9 40.0 33.8
February 31.1 39.2 39.9 30.1 37.4 36.7 35.2 33.8 39.9 38.8
INDEX 101 .7 112.0 116.4 113.3 116.6 110.5 103.3 99.4 123.1 103.8

Average monthly temperatures in °F at Newark, DE Experiment Station. 2000-2010.

2009-2010 2008-2009 2007-2008 2006-2007 2005-2006 2004-2005 2003-2004 2002-2003 2001-2002 2000-2001
December 34.9 37.1 37.5 42.5 34.0 35.5 34.0 33.5 43.3 31.1
January 31.6 28.0 35.5 37.3 39.5 31.0 26.4 27.1 39.6 31.5
February 31.0 35.8 36.5 27.8 34.5 34.2 33.1 29.5 40.1 38.4
INDEX 97. 5 100.9 109.5 107.6 108.0 100.7 93.5 90.1 123.0 101.0

Severity Index: < 90, usually absent; 90-100, intermediate; >100, usually severe.

The index is used to predict overwintering flea beetle populations that vector the Stewart’s wilt bacterium, Pantoea stewartii.

Note: Weather records from University of Delaware Carvel REC, Georgetown, DE and University of Delaware Ag Experiment Station Farm, Newark, DE. Data records found online at http://www.deos.udel.edu/

Information on Potato and Tomato Late Blight Management

Thursday, March 25th, 2010

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

With the widespread occurrence of late blight last season on tomato and potato. There is some new information available from other universities that might be of interest. Dr. Meg McGrath, Cornell plant pathologist on Long Island, has written two articles on managing late blight organically, both of which are available online: Managing Late Blight in Organically-Produced Potato and Managing Late Blight in Organically-Produced Tomato.

Dr. Tom Zitter, also from Cornell, compiled a list of tomato varieties with reported resistance to late blight and early blight that might be helpful: Table of Late Blight and Early Blight Resistant Tomato Cultivars

Fungicide Guide for Managing Resistance of Fungi on Vegetable Crops Available Online

Thursday, March 25th, 2010

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

New Jersey Cooperative Extension has both the 2010 Commercial Vegetable Production Guide online as well as the FRAC guidelines for managing fungicide resistance on vegetable crops. There is much more at this site as well, and it is a good source of information at your fingertips. Both publications are also available free at the Delaware Extension offices. The website is http://njveg.rutgers.edu. The Production Guidelines are under Growing Crops and the FRAC Guidelines are under Controlling Pests-IPM. The FRAC Fungicide Guide for vegetables is also posted on the UD Plant Clinic site http://ag.udel.edu/plantclinic. We will soon have the 2010 Commercial Vegetable Production Guide online as well.