2015 Occurrence of Sugarcane Aphid in the U.S. and Mexico With Reference to Occurrence in 2013 and 2014

Robert Bowling*1, Michael Brewer1, Stephen Biles2, John Gordy31Texas A&M Agrilife Research and Extension Center, Corpus Christi, Texas

2Texas A&M Agrilife Extension, Port Lavaca, Texas3Texas A&M Agrilife Extension, Rosenberg, Texas

*Corresponding Author

ABSTRACT:

The sugarcane aphid (SCA), Melanaphis sacchari (Zehntner), occurrence on sorghum was mapped in 2015. Highlights of SCA occurrence in 2015 included substantial and re-occurring populations along the Texas and Mexican Gulf Coast, early detecting in the High Plains of TX where it was reported in the South High Plains and Northern High Plains by August. These reports were two months earlier than 2014 reports. The Aphid moved across Kansas up to the KS NE border. SCA was not confirmed on Sorghum in NE. There were 5 new state records where SCA was confirmed on sorghum in 2015 including NM, CO, IL, KY, and VA. In 2015, 17 states and over 400 counties had confirmed reports of SCA on sorghum, along with extensive reports from Mexico. In the U.S., this is a 25% increase in occurrence from 2014. In 2015, the 17 states with confirmed sugarcane aphid on sorghum accounted for 97% (7,405,000 acres) of the sorghum acres and 98% (560,253,000 bushels) of total sorghum production in the U.S. (USDA-NASS, 2015).

IntroductionIn 2013, abundant sugarcane aphid, Melanaphis sacchari, were reported on sorghum in South Texas through north-central Texas, Louisiana, and one county in Oklahoma and Mississippi. The aphid was reported in sorghum from 4 states and 38 counties (see map above). Although the aphid caused significant sorghum production issues in 2013, there was uncertainty as to the aphid’s ability to become established as a major sorghum pest beyond selected southern production areas in the U.S. Here we report occurrence of sugarcane aphid in 2014 and 2015 throughout the growing season from sorghum production regions in the United States and Mexico.

2014In 2014, the aphid expanded its range to 11 states and 311 counties, including records as far north to Kansas, east to Georgia and Florida, and west to the Texas and Oklahoma High Plains, making it one of the most prolific sorghum pests in the U.S. The latest report for sugarcane aphid in sorghum showed a continued expansion north into the northern TX High Plains and a new county record in KS. There are unconfirmed reports of sugarcane aphid on sorghum in Missouri and possibly Kentucky. More importantly, the occurrence of sugarcane aphid in Florida suggests a new potential overwintering site for the aphid added to overwintering in south Texas.

In 2014, the 11 states with confirmed sugarcane aphid on sorghum accounted for 87% (5,710,000 acres) of the sorghum acres and 76% (294,000,000 bushels) of the total sorghum production in the U.S. (USDA Crop Production 2013).

May 2015Early in 2015, the sugarcane aphid was reported on sorghum from the coastal bend and Lower Rio Grande Valley in Texas with spotty reports of the aphid infesting sorghum from AR and AL. Populations in South Texas were below or at threshold through June. Fewer than 25% of the sorghum acres were treated for sugarcane aphid infestations in South Texas during the 2015 production season.

August 2015Sugarcane aphid populations expanded into SE NM, the northern TX High Plains, and south-central and eastern KS by the end of August. Large sugarcane aphid populations on sorghum were widespread in NM and across the southern High Plains of Texas. Reports of treatable infestations of the aphid on sorghum in the northern High Plains of TX, OK, and KS were sporadic. The expansion of sugarcane aphid in the TX High Plains occurred two to three months earlier when compared with infestations in 2014. Reports of the aphid in NM and KY were new state records. Its early expansion in eastern KS was unexpected and puts at risk sorghum production in the two largest sorghum production regions in the U.S.

MayJulyAugust

MayJuly

July 2015In July, the sugarcane aphid was confirmed on sorghum in the South High Plains of TX, OK, KS, across the mid-south and into the SE region of the U.S. Its expansion across sorghum production regions was rapid and may have coincided with high ambient temperature and drought conditions. The majority of sorghum acres in the South TX High Plains, OK, the mid-south, and SE U.S. were treated for sugarcane aphid. Some fields were treated multiple times.

MayJulyAugustSeptember

September 2015The sugarcane aphid on sorghum continued its northward expansion with new state records in CO, IL, and VA. The aphid had exceeded the threshold on sorghum grown in these states. The aphid on sorghum also had numerous county records in KS.

2015 Sugarcane Aphid on Sorghum in Mexico and the U.S.The sugarcane aphid is an economic pest of sorghum grown in North America including all sorghum production regions in Mexico and the majority of sorghum regions in the U.S. In 2015, large and persistent populations of the aphid in Mexico caused crop failures in some sorghum production regions although multiple insecticide applications were applied to manage the aphid. Sugarcane aphid populations threatened sorghum across the U.S. but was more of a threat to sorghum in the southern TX High Plains, portions of KS, and in the mid-south and southeast production regions.Sugarcane aphid populations in south TX were smaller than experienced in 2014. Heavy rainfall in the first six months of 2015, cooler temperatures, and abundant natural enemies may have been factors influencing its ability to be a widespread threat to sorghum production in southern regions of TX. In 2015, 17 states and over 400 counties had confirmed sugarcane aphid on sorghum. These sorghum production regions account for 97% (7,405,000 acres) of the sorghum acres and 98% (560,253,000 bushels) of the total sorghum production in the U.S. (USDA-NASS, 2015).

Confirmation By: Location Confirmation By: Location Confirmation By: Location

Nick Seiter AR Charles Allen TX Jane Pierce NM

Gus Lorenz AR Danielle Sekula‐Ortiz TX Sarah Zukoff KSGleen Studebaker AR Stephen Biles TX Glenn Studebaker MOKathy Flanders AL Scott Willey TX Brent Bean NC

David Buntin GA Sid Hopkins TX J. P. Michaud KS

David Kerns LA Mike Treacy TX Russell French TX

Sebe Brown LA Roy Parker TX Moneen Jones MO

Jeff Gore MS Ed Bynum TX Tim Kring AR

Angus Catchot MS Olan Moore TX Jason Duval TX

Rick Kochenower OK Jody Stockett TX Jason Schniederjan TX

Tom Royer OK Mark Scott TX Scott Armstrong OK

Scott Stewart TN Ronnie Schnell TX Cleve Franks TX

Allen Knutson TX Blayne Reed TX Mike Gray IL

Robert Bowling TX Kerry Siders TX Travis Kidd VA

Michael Brewer TX Brad Easterling TX Mace Bauer FL

Raul Villaneuva TX Francis Reayjones SC Salvador Vitanza TX

John Gordy TX Pat Porter TX Matt Bartek TX

Tommy Doederlien TX Chris Cernosek TX

This poster and additional information is available at http://ccag.tamu.edu/sorghum-insect-pests

The following individuals are thanked for their contributions to the 2015 maps.