Introduction

1. Introduction The sugarcane beetle, EuetheolahumilisrugicepsBurmeister, is a significant insect pest of sweetpotato, Ipomoea batatas L., in Louisiana, and a sporadic pest of Mississippi sweetpotato production. Adult sugarcane beetles move into sweetpotato fields late in the production season and chew large holes in the root. They are often found burrowed in the root during harvest. Soil incorporated insecticides and avoiding damage by early transplanting dates are used by growers for control of sugarcane beetles in sweetpotato fields. In 2011 USDA, ARS, Southern Insect Management Research Unit (SIMRU) and LSU AgCenter collaborated to evaluate six insecticides regimes for efficacy against sugarcane beetle in sweetpotato. A cage study was conducted at the SIMRU location in Stoneville, MS. Beauregard sweetpotatoes were transplanted to four row plots in the 1/8 acre field cages (14 plots per cage), treatments applied and all plots were infested with sugarcane beetles 36 days before harvest. Treatments were arranged in a RCB design and replicated four times. Sweetpotatoes were harvested from the two center rows of each plot. Yield, quality and insect damage were recorded and analyzed. Twenty-five roots per plot were chosen randomly and evaluated for insect damage after washing. Sugarcane beetle damage ranged from 1.0 to 33.00 percent in this study. Preplant applications of Belay 2.13 SC, Lorsban 4E and Admire Pro resulted in significantly less damage compared to the untreated control plots. Summary The highest percent of the root damage in the trial was identified as sugarcane beetle feeding punctures. Sugarcane beetle damage ranged from 1.0 to 33.0 percent (Table1). All treatments, with the exception of the Belay layby treatment resulted in significantly less sugarcane beetle damage when compared to the non-treated control plots. The Admire Pro plus Lorsbanpreplant plus Belay layby plus a weekly foliar spray treatment resulted in significantly less sugarcane beetle damage than the Lorsbanpreplant plus Belay layby, the Admire Pro preplant and the Admire Pro preplant plus Belay layby treatment. Wireworm damage ranged from 2.0 to 18.0 percent (Table 1). All treatments with the exception of the Belay layby treatment significantly reduced wireworm damage when compared to the non-treated control plots. No significant difference in yield was obtained from any of the treatments when compared to the non-treated control plots (Chart 1). 2011 Sugarcane Beetle Cage Study Yield Results Evaluation of Various Insecticide Regimes in Sweetpotato Productionfor Sugarcane Beetle Control in the Mid-SouthLarry Adams1, Randall Luttrell1 and Tara Smith21USDA, ARS, SIMRU, Stoneville, MS2LSU AgCenter, Chase, LA Material and Methods Research Plot Design Beauregard 63 sweetpotato slips were transplanted on June 1, 2011. Four row plots by 20’ were replicated four times (RCB) in large screen field cages. Row width was 40” and the slip spacing was 12”. Recommended herbicides and a nematicide treatment were applied before transplanting. All plots were irrigated as needed throughout the season. Test plots were harvested by hand on October, 6, 2011 at 127 days after transplanting. Insect Sampling Sweep Net samples were taken weekly using a 15” sweep net with 100 sweeps at intervals of 25. Insect populations were recorded. Sugarcane beetles were collected in black light traps and 40 beetles were released in each plot (1 per plant on the two center rows) on August 31, 2011 (36 days before harvesting the two center rows). Preplant Incorporated Insecticide Treatments Applied on 5/25/2011 • Admire Pro 4.6 E @ 10 oz/A • Belay 2.13 SC@ 12 oz/A • No PrelantTreament • Lorsban 4 E @ 64 oz/A • Admire Pro 4.6 E @ 10oz/AplusLorsban 4 E @ 64 oz/A • Admire Pro 4.6 E @ 10 oz/A • UTC Layby Insecticide Treatment Applied on July 19, 2011 • Belay 2.13 SC @ 12 oz/A • No LaybyTreament • Belay 2.13 SC @ 12 oz/A • Belay 2.13 SC @ 12 oz/A • Belay 2.13 SC @ 12 oz/A • No Layby Treatment • UTC Weekly Insecticide Treatments Applied to Treatment 5 • Capture 2 EC @ 6.4 oz/A - 7/26/2011 • Baythriod XL @ 3.0 oz/A - 8/3/2011 • Mustang Max EC @ 21 oz/A – 8/10/2011 • Baythroid XL @ 3 oz/A – 8/18/2011 • Mustang Max EC @ 21 oz/A – 8/25/2011 • Capture 2 EC @ 6.4 oz/A - 9/1/2011 • Baythroid XL @ 3 oz/A – 9/8/2011 Lbs per 40’ of Row Harvested Treatments: 1) Admire Pro 10oz/A – Preplant 5) Admire Pro 10oz/A plus Lorsban Belay 12oz/A – Layby 64oz/A - Preplant Belay 12oz/A – Layby 2) Belay 12oz/A – Preplant Selected Treatment Weekly 3) No Treatment – Preplant 6) Admire Pro 10oz/A – Preplant Belay 12oz/A – Layby 4) Lorsban 64oz/A – Preplant 7) Non-Treated Control Belay 12oz/A – Layby Acknowledgement We thank Chris P. Johnson, Owen Houston and Phil Powell, USDA, ARS, SIMRU, for their assistance in field plot preparation, maintenance and harvest, Debbie Boykin, USDA, ARS, Statistician, for assistance with the statistical analysis of the data in this study, and T. Arnold, LSU Agricultural Center, for assistance in collecting insects for this study. A – Larvae Stage B – Pupae Stage C – Adult Stage