Assessing resistance to Piezodorus guildinii (Westwood) in six soybean cultivars

Though insect resistance has been a goal of U.S. public soybean breeding programs, no cultivars have been released with stink bug resistance and only three cultivars have been released with Lepidopteran resistance. These cultivars have not been accepted by growers due to low yields and late maturity. The objective of this study was to evaluate commercially available cultivars which are high yielding and maturity group appropriate for resistance to stink bugs. In 2009 and 2010, six commercial soybean varieties were planted at the Ben Hur Research Station, Baton Rouge, LA. Plots were 4 rows wide by 25 ft in length and treatments were arranged in a RCBD with four replicates. Native stink bug populations were assessed weekly during soybean growth stages R1 to R8 using a standard sweep net to take 25 sweeps per plot and counting number of nymphs and adults collected per stink bug species. Cumulative stink bug days (CSBD) were then calculated. At harvest, yields were recorded and seed was assessed for quality. In 2009, 60% of stink bugs collected were redbanded stink bug, Piezodorus guildinii (Westwood), and in 2010, 50% were redbanded stink bug. In both years, Pioneer 95Y20 had the lowest redbanded CSBD; 8.4 in 2009 and 18.2 in 2010. The highest redbanded CSBD occurred in Terral TV48R14 (120.1) in 2009 and Progeny 4906RR (73.5) in 2010. Pioneer 95Y20 had the least damaged seed for both years (15.2%) while Progeny 4906RR had the most (45.2%).