Section18 request granted for SCA in sorghum

Good news!

It was just announced this week that we were granted a Section 18 request that allows the use of Transform (Sulfoxaflor) on grain sorghum in Texas for control of the sugarcane aphid, Melanaphis sacchari. This is very good news because now we have TWO effective insecticides that can be used to control SCA populations, but still preserve natural enemies. These are Sivanto and Transform. 

Very important: the user must have the label in their possession at the time of application!! 

Some label specifics: 

(compiled by Dr. Pat Porter on Texas Sugarcane Aphid News)

• Rate range: 0.75 to 1.5 oz. per acre.
• Application by ground or air (no chemigation).
• Wind speed not to exceed 10 mph.
• Droplet Size: Use only medium to coarse spray nozzles (i.e., with median droplet size if 341 μm or greater) for ground and non-ULV aerial application according to ASABE (S 572.1) definition for standard nozzles. In conditions of low humidity and high temperatures, applicators should use a coarser droplet size except where indicated for specific crops.
• Boom height for ground application: Not to exceed 4 feet.
• Carrier volume for ground application: A minimum of 5 to 10 gallons per acre - to be increased with increasing crop size and/or pest density.
• Carrier volume for aerial application: A minimum of 3 gallons per acre, but a minimum of 5 gallons per acre is recommended.

Restrictions:

• Preharvest Interval: Do not apply within 14 days of grain or straw harvest or within 7 days of grazing, or forage, fodder, or hay harvest.
• A restricted entry interval (REI) of 24 hours must be observed.
• Do not make more than two applications per acre per year.
• Minimum Treatment Interval: Do not make applications less than 14 days apart.
• Do not apply more than a total of 3.0 oz of Transform WG (0.09 lb ai of sulfoxaflor) per acre per year.
• Do not apply product ≤ 3 days pre-bloom until after seed set.

You can read the entire label for Transform at the Texas Department of Agriculture's website.

What Texans Need to Know about Zika Virus!

As we get closer and closer to mosquito season, I want to reiterate how important it is to stay informed about the situation regarding mosquitos and Zika virus. The more data we get, the stronger the link between Zika virus and disorders such as Microcephaly, which results in underdeveloped brains and skulls, and Guillain-Barré syndrome, an autoimmune disease that can cause paralysis. 

To help reduce the risk, get rid of any standing water around your home where mosquitos can breed. This includes tires, buckets, flower pots, gutters, dog bowls not currently being used, bird baths, and even bottle caps. Secondly, wear appropriate clothing when you're outside and always use mosquito repellant.

Professors and Extension Entomologists Dr. Sonja Swiger and Dr. Michael Merchant have put together a fact sheet What Texans Need to Know about Zika Virus. It contains some great information as well as links to additional facts, so definitely check it out.

A vector of the Zika virus, the yellow fever mosquito, Aedes aegypti. Photo: cdc.gov 

Sugarcane Aphid Update!

The sugarcane aphid, Melanaphis sacchari, is slowly starting to show up in parts of Texas. Make sure you are prepared this growing season! Familiarize yourself with the sugarcane aphid, SCA, so you know what you are dealing with (see below). If you are planting grain sorghum, get it in early to avoid plant damage in those early, vulnerable growth stages. Also, we recommend using a neonicotinoid seed treatment, which provides approximately 45 days of protection for $2/acre.

IPM Agents and Extension Entomologists are currently monitoring overwintering traps for this year, but so far we know that the SCA is moving north through Texas much faster than it has previously. Xandra Morris, IPM Agent – Hill county, reported finding the sugarcane aphid (SCA) south of Itasca on newly emerged Johnsongrass on February 18. This is five weeks earlier than the SCA was found last year.  

Most recently, students at Roscoe Collegiate High School in Roscoe found that SCA have successfully overwintered in Nolan County (many thanks to students Crystal Alvarez, Kelsi Vrubel, Katelyn Collins, and Matthew Buckley for conducting the overwinter study and to Roxanna Reyna-Islas, Extension Program Specialist 4-H, who helped the students!). They reported their findings to Extension Entomologist Dr. Pat Porter who confirmed the identity of the SCA. This is the farthest north that SCA have been confirmed to overwinter. You can read about their findings on the Texas Sugarcane Aphid News website which is full of useful information, current updates, and resources.

Pest Aphids in Winter Wheat

Temperatures are on the rise and so is aphid activity! There have been reports of aphids popping up all over Texas recently, so if you haven’t already, make sure to get out and scout fields for three common species:

Bird cherry-oat aphid, Rhopalosipum padi

Greenbug, Schizaphis graminum

Russian wheat aphid, Diuraphis noxia

Mark Brown (Lubbock Co Ag Agent) and I stopped in a wheat field the other day in Lorenzo, TX. Mark noticed purple, longitudinal streaks down the leaf steam and wrapped up inside was a colony of Russian wheat aphids (see photo below). Russian wheat aphids, RWA, feed in the whorl of new plant shoots and the plant curls around the aphids, protecting them from damage. The saliva of Russian wheat aphids is toxic to plants and this is what causes the discoloration.

Russian wheat aphids on winter wheat in Lorenzo, TX.

Greenbugs are similar in color to the Russian wheat aphid, but have a characteristic green stripe down their back and longer antennae and cornicles than the RWA. Damage by greenbugs appears as brown or orange leaves that appear to be ‘scorched.’ As the infestation increases and spreads out, discolored patches are visible in the wheat.

Bird cherry-oat aphids are smaller, olive green colored aphids with pink coloration on the underside. Their numbers have been on the rise down in Hill County, according to Xandra Morris (IPM Agent). Check out her blog on BCOA for scouting tips and thresholds!

The good news is that beneficials are out and have the ability to suppress RWA populations. I’ve seen green lacewing eggs on wheat as well as pink-spotted ladybeetles (Coleomegilla maculata). When inspecting your fields, take into account the predators and parasitoids that will provide natural control when making the decision to treat. Use this Cereal Aphid Decision Tool by Oklahoma State University to help with aphid management. Dr. Ed Bynum (Extension Entomologist– Amarillo) has information on economic thresholds for RWA developed by Texas A&M Agrilife Extension.