SUGARCANE APHID UPDATE

MANAGEMENT OF SUGARCANE APHID ON GEORGIA SORGHUM IN 2016

David Buntin, Grain Crop Entomologist, UGA-Griffin Campus (gbuntin@uga.edu)

In late August 2014 a new aphid was found attacking grain sorghum in Georgia.  This aphid is the sugarcane aphid (Melanaphis sacchari).    Sugarcane aphid will be a serious pest of sorghum in 2015 with most fields being treated one or more times.   Infestations are developing throughout the state mostly in the coastal plain region now.   I expect the aphid to be throughout the state very soon in 2016.

Background:  The sugarcane aphid (SCA) has occurred in Florida since 1977 and Louisiana since 1989 feeding on sugarcane.  About 2 years ago the aphid shifted hosts and a strain with a preference for grain and forage sorghums appeared.  First found in eastern Texas near Beaumont, this new strain has rapidly spread eastward across the southern United States in 2014.  It is now widespread across the southern U.S. and occurs from Texas, Oklahoma and southern Kansas to central Florida, most of Georgia and as far east as southeastern Virginia.  The aphid infests all types of sorghum including Johnsongrass, Sorghum halepense.  Indeed Johnsongrass supports populations in areas were grain sorghum is absent.  The aphid must overwinter on green sorghum plants in areas where volunteer sorghum and Johnsongrass do not go completely dormant.

 

Photos: Xinzhi Ni, USDA-ARS, Tifton, GA and  Pat Porter, Texas A&M AgriLife Extension

Identification: It is important to scout sorghum fields in your area for its presence.   It is fairly easy to identify.  Wingless forms are a uniform pale cream to yellow with black feet and black cornicles (the small tubes present on the end of the abdomen).

Damage: Where it has been found in Georgia, it is present at very high numbers of several thousand aphids per plant across entire fields.  Large populations of fluid sucking aphids cause serious injury to the plants including death of leaves and sometimes plants. Feeding injury causes reddish lesions on the stems and leaves.   Studies have showed that the greatest yield losses occurred during pre-boot, boot and early panicle emergence stages with yield losses of 52 – 100%.  Pre-boot infestations at this time can prevent heading and infestations during boot and early panicle emergence can cause sterile heads.   Infestations during soft dough also reduced yield by about 20%. The aphid can remain present in large numbers in the field until harvest.  It produces large quantities of honeydew, a sticky sugary substance that adheres to the plants, which may interfere with harvest and could damage combine harvest equipment.

Management Practices for SCA Aphid

1) Plant early – Because the aphid migrates northward in the spring, early plantings may avoid may avoid very large infestations.   Late planted double-crop plantings are at greater risk of severe infestations.   Some hybrids have been shown to have some partial tolerance to the aphid.   This table from LSU lists grain sorghum hybrids with some degree of tolerance to SCA. http://www.lsuagcenter.com/NR/rdonlyres/EF5A0F6C-B46D-4C16-9E8F-C355F5B7DE90/105488/Pub3523SorghumHybrids_FINAL.pdf

2) Use an insecticide seed treatment.   My trials last year found that insecticide seed treatment would limit seedling infestations for 30 – 40 days after planting.   All registered neonicotinoid insecticides are effective including thiamethoxam (Cruiser), clothianidin (Poncho, NIpsIt Inside) and imidacloprid (Gaucho, others).   Most grain sorghum seed was treated with one of these seed treatments in 2016.

3) Scout early and often.   Fields can quickly be inspected for the presence of aphids by looking are on the underside of leaves.  Once aphids are detected, scout at least once, preferably 2 times per week, because aphid numbers build very quickly.  Shinny lower leaves with honeydew are a clear sign of infestation.

4) Beneficial insects usually do not control infestations.   SCA and their honeydew attract large number of beneficial insect predators such as lady beetles, syrphid fly larvae and lacewings.  A parasitic wasp is present in and caused infested aphids to turn a dark blue-gray color.    No aphid fungal disease has been observed either.  Generally the rapid rate of increase in aphid populations overwhelms the beneficial insects and severe plant damage usually occurs.

5) Treat when aphids reach threshold levels.  The current threshold is 50 or more aphids per leaf on 25% pf plants preboot stage through dough stage.  Once threshold is reach do not delay application because infestations can very quickly go from the threshold level to 100% infested plants and hundreds of aphids per leaf.

6) Use an effective insecticide.  PYRETHROID INSECTICIDES ARE NOT EFFECTIVE and may flare infestations by killing all the aphid predators.  Regardless of the insecticide, rapidly expanding populations are difficult to control.  Foliar insecticide options for SCA in Georgia are:

  • Sivanto Prime (Bayer Crop Protection).  Sivanto prime has a full section 3 label and a supplemental 2ee label for lower rates on sorghum and other grain crops.  The 2ee rates are 4 – 7 fl. oz per acre.  Sivanto was very effective in my trials at rates of 4 to 7 fl. oz. per acre with Control usually lasting 21 days or more.  At the 4 oz rate it can be applied up to 7 times during the season but has a 21 day PHI.
  • Transform WG (Dow AgroSciences). Transform WG federal label was vacated last winter and a new federal label has not been approved yet.   But Transform WG has an approved Section 18 emergency exception for use on sorghum in Georgia in 2016 through April 8, 2017. The big label change for 2016 is Transform cannot be used during bloom to protect pollinators. The label allows for 2 applications per season and not more than 3 oz per acre per crop and has a 14 day PHI.   In my insecticide trails last season, rates of 1.0 and 1.5 oz per acre were effective.  Use the 1.5 oz rate if aphid populations are increasing rapidly.
  • Chlopyrifos (Lorsban Advanced, Nufos, other).   Lorsban is labeled at 1 to 2 pints per acre.  The 2 pint rate has a 60 day harvest interval.  The 1 pint has a 30 day harvest interval, but is usually not effective.   The 2 pint rate was 60-90% control for up to 2 weeks.  At the 2 pint rate it cannot be used after the boot stage due the 60 day PHI.   DO NOT USE CHLORPYRIFOS ON SWEET SORGHUM.
  • Dimethoate ( Dimethoate, Cygon).   Not recommended.  In my trials dimethoate is variable in control and control if it occurs is only for a week or so.

7) Good coverage is key to effective control.  Use tips and GPA for maximum coverage especially lower in the canopy. A minimum of 10 gpa by ground and 5 gpa by air is highly recommended.

8)  Avoid pyrethroid insecticides for other sorghum pests.   For sorghum midge try to avoid routine pyrethroid sprays for sorghum midge.  Instead scout and treat at 1 adult per panicle.  Chlorpyrifos (1 pint per are) for low to moderate infestations.   If pyrethroids are used they can be tank mixed with Sivanto (Do not use Transform during bloom).   Early plantings often avoid serious midge infestations.  For fall armyworm in the whorl, the threshold is 50% infested whorls.  Use Belt, Prevathon or Lannate which are specific to caterpillars.  For headworms, corn earworms fall armyworm, sorghum webworm, the threshold is 1 worm per head and use Belt, Prevathon, Beseige or Lannate.

9) Check fields 2-3 weeks before harvest for infestations.   A treatment may be needed if large numbers are in the head to prevent damage to combines.  Hybrids with taller stalks and more space between the grain and upper leaves may make harvest easier by reducing the amount of leaf material going through the combine.  Large infestation producing large amounts of honeydew and sooty mold may interfere with harvest desiccants.  Transform WG can be applied up to 14 days before harvest.

10)  Silage/forage sorghum control.  No work was done specifically on SCA control in silage/forage sorghum last year, but I and Dennis Hancock have some trial out this year.  So the same recommendations for grain sorghum also apply to silage and forage sorghum.   Both Sivanto prime and Transform can be used on silage and forage type sorghums.   Grazing / hay interval is 7 days for both products.  In forage/hay types, the later cutting were damaged last year.  Spray coverage is difficult when plants get tall.  If aphids are present but below threshold consider a spray application as late as possible before the crop gets too tall.

11) Sweet sorghum.  Sivanto prime, Transform and chlorpyrifos cannot be used on sweet sorghum.  There are no effective treatment options for sweet sorghum.

Summary.   Most likely SCA will infest sorghum statewide in Georgia in 2016.  SCA will be difficult to manage cost effectively.   Planning and scouting will be keys to successfully managing this new invasive pest and prevent serious losses to sorghum in Georgia in 2016.

 

Tim Smith

County Coordinator

Agricultural and Natural Resources Agent

UGA Extension – Wilcox County

SOYBEAN UPDATE

Plantation Seed

SOYBEAN UPDATE

June 1, 2016

 

 

Soybeans  are entering the stage where you need to watch for Disease that can rob yield

and hurt quality.  Three cornered Alfalfa Hoppers are really out in force please check before they hurt you.

 

Attached you will find photos and descriptions of the major diseases encountered in your fields.

 

 Soybean Diseases descriptions

Soybean Diseases 1 and 2 photos

 

Go to plantationseedupdate. for details on Ultra Late planting.

Always follow label directions and  wash all empties completely.

 

 

Good Growing   Blake, Lee, Lane, Brett, amd Jimmy

800-543-4164

 

SOYBEAN UPDATE

Plantation Seed

SOYBEAN UPDATE

May 11, 2016

 

Seeding rate  is one of the first steps toward a good yield. Soybeans have from 2200 seed per lb to 4500 seed per lb.  Do not go by pounds per acre .  30” rows at 8 seed per foot will use  59 pounds per acre of a 2250 seed/lb soybean and only 41.4 pounds per acre of a 3600 seed/lb. soybean.  You want about 145,000 seed per acre. For normal planting dates. Call if you plan to palnt HIGH yield irrigated soybeans this year.

 

SEEDING RATE

36” rows  9-10 seed per foot

30” rows  8- 9 seed per foot

21 to 24” rows  6- 7 seed per foot

15 to 16” rows  5- 6 seed per foot

  7 ½  to 8” rows  2- 4 seed per foot

Twin peanut type rows  5-7 seed  per foot

 

LATE PLANTING

If you are planning to plant after June 30 please order your beans now and ask your dealer to advise your seedsman to place these late planted beans in cool storage. This will maximize your chance of getting high germing soybeans for your late planting needs. There are several group 5, 6, and 7 beans that have yielded very well planted late. Go to plantationseedupdate. for details on Ultra Late planting.

Always follow label directions and  wash all empties completely.

 

 

Good Growing   Blake, Lee, Lane, Brett, amd Jimmy

800-543-4164

 

*Some information obtained from 2015 Georgia Pest Control Handbook,                       Soybean Diagnostic Guide, and Pioneer.

*** As always follow label and dispose of empties properly.

 

OAT RUST UPDATE

PLANTATION SEED
OAT RUST UPDATE
03-23-16

Below you will find a photo of Crown Rust in oats.
This has been found by Thomas Wray (Photo) in Baker Co and Ed Harrison in Thomas Co.
The Warm winter and high temp for the next few days is perfect for rust to spread.

Folicur of one of the generics will work very well and you may want to put in an insecticide if you have Aphids in the field.

Good Growing
Blake, Lane, Lee, Brett, and Jimmy

*Follow label on all Pesticides, rinse, and dispose of empties properly. Info Georgia Pest Management Handbook 2016, USDA Data, and Christina Cowger.

Crown Rust Oats

FHB SPRAY UPDATE

PLANTATION SEED

FHB SPRAY UPDATE

04-11-16

In the link below, you will find a photo of wheat flowering and a slide of best time to spray for FHB control.

FHB Spray best time

5-7 days after your wheat strarts flowering, (this should occur around 04-12 to 04-20) put out Caramba, Proline, or Prosaro. (make sure your dealer has product in stock for you) This approach should decrease your exposure to FHB (not complete control, to get better you will need a wheat with the FHB gene and apply the fungicide) while keeping the other diseases in check.

 

Good Growing

Blake, Lane, Lee, Brett, and Jimmy

 

 *Follow label on all Pesticides, rinse, and dispose of empties properly. Info Georgia Pest Management Handbook 2016, USDA Data, and Christina Cowger.

Wheat/Oat Grower Update

Please see correction on timing of FHB spray from Christina Cowger, last update was in error.

Important note from Christina: If scab is your target, you will only profit significantly if you apply fungicide between early flowering and up to 7 days later. Fungicide applications before flowering will give little to no scab control. This is because the scab fungus attacks the heads through the flowering parts (anthers) once they are extruded.

Bottom line: use Propiconazole or Tebuconazole to correct any early problems. Then, if there is medium to high risk of scab, which you can see at the forecasting site www.wheatscab.psu.edu, put out Caramba, Proline, or Prosaro at early flowering or, if it is too wet then, up to 7 days later. This approach should decrease your exposure to FHB while keeping the other diseases in check. I will be sending out FHB update as soon as I prior to wheat flowering.

APHIDS 

Foliar insecticide treatments for aphid control: A well-timed insecticide application of a persistent pyrethroid insecticide such as lambda cyhalothrin (Warrior, Karate, Lambda, Silencer,other(s) will kill aphids and reduce the incidence of BYD and increase yields.

Good Growing!

Information from: Christina Cowger, Small Grains Pathologist USDA-ARS North Carolina State University, Intensive Wheat Management in Georgia and 2015 Georgia Chemical Handbook.

Wheat Harvest Update

If you have some time, below is a link to a very good article. But if you don’t have the time, the meat of the article on combine settings is below. 

Article: Identification and Control of Fusarium Head Blight (Scab) of Wheat in Georgia

If people ask about how to adjust the combine in a high-scab field:  Research at the Ohio State University showed that adjusting the combine’s fan speed between 1,375 and 1,475 rpms and shutter opening to 90 mm (3.5 inches) resulted in the lowest discounts that would have been received at the elevator due to low test weight, % damaged kernels, and DON in the harvested grain (Salgado et al., 2011; PDF at http://plantpath.osu.edu/sites/plantpath/files/imce/files/Paul/PDIS-01-14-0093-RE.pdf)

Follow the below to help reduce vomitoxin in your wheat harvest.

Harvest Techniques To Reduce Fusarium Infected Kernels

Adjust combine so lightweight, shriveled kernels are also removed with chaff. The goal is to blow the lightweight, diseased kernels out the back of the combine without blowing out too many good kernels. This technique is feasible when the rest of the grain is of good quality. In fields severely affected by leaf diseases, the lower test weight of the grain may make it more difficult to separate normal kernels from Fusarium damaged kernels.

Source for above UGA extension

Good Growing!

** As always follow label and dispose of empties properly.**

Wheat Update

These photos were taken today (4/19/15) south of Blountstown, Fl.  I have never seen a field so completely covered with rust and septoria. This could happen to your fields if you did not spray on time. At first I thought Wheat Take All, but this is the first I have seen wheat in this field. It was following peanuts. This field has had rain for several days straight.

Diseased  wheat in FlaDiseased wheat fla 04-19-15

You need to spray as late as possible per the label of fungicide used, because most fungicides do not translocate well in the plant. We need to protect the head of wheat and the flag leaf during this time.   If you see rust call me. I have seen very little rust but lots of Septoria, Stagonnospora leaf blotch, Powerdery mildew, BYD and Tan Spot.

Fungicides

Absolute 500 SC, Headline , Stratego, Quilt, Quadris, Folicur+Tilt , or one of many others.  All should be put out at per the label of fungicide used.

Aphids are out , but you need to have 10+ per flag leaf before you treat. Always watch for beneficials. Lady bugs, Aphid lions (lady bug larvae), parasitic wasp, and syrphid fly larvae all eat aphids.

Foliar insecticide treatments for aphid control: A well-timed insecticide application of a persistent pyrethroid insecticide such as lambda cyhalothrin (Warrior, Karate, Lambda, Silencer, others) can reduce the incidence of BYD and increase yields.  Lambda cyhalothrin can only be applied twice to a crop so use another product at heading such as Baythroid XL or Mustang MAX/Respect.  These can be combined with a foliar fungicide application and also will control cereal leaf beetle if it is present.

Always follow all label instructions.

Good Growing!

*Follow label on all Pesticides, rinse and dispose of empties properly. Info Georgia Pest Management Handbook 2015

Soybean Update

Seeding rate is one of the first steps toward a good yield. Soybeans have from 2200 seed per lb to 4500 seed per lb. Do not go by pounds per acre. 30” rows at 8 seed per foot will use 59 pounds per acre of a 2250 seed/lb soybean and only 41.4 pounds per acre of a 3600 seed/lb. soybean. You want about 145,000 seed per acre for normal planting dates.

SEEDING RATE

36” rows 9-10 seed per foot

30” rows 8- 9 seed per foot

21 to 24” rows 6- 7 seed per foot

15 to 16” rows 5- 6 seed per foot

7 ½ to 8” rows 3- 4 seed per foot

Twin peanut type rows 5-7 seed per foot

LATE PLANTING: If you are planning to plant after June 30 please order your beans now and ask your dealer to advise your seedsman to place these late planted beans in cool storage. This will maximize your chance of getting high germing soybeans for your late planting needs. There are several group 5, 6, and 7 beans that have yielded very well planted late.

Always follow label directions and wash all empties completely.

Check out new lower prices on AGSouth beans

 AGS 828 RR  # 8 irrigated 2 year State wide Group 7 & 8

AGS 5911 LL # 5 dryland 2014 Tifton Group 5

AGS 738 RR   # 1 irrigated 2 year Tifton Group 7 & 8

Good Growing!

*Some information obtained from 2015 Georgia Pest Control Handbook, Soybean Diagnostic Guide, and Pioneer.

*** As always follow label and dispose of empties properly.