PLANTÐINSECT INTERACTIONS Influence of Soybean Planting Date and Maturity Group on Stink Bug (Heteroptera: Pentatomidae) Populations

Field experiments were conducted in Stoneville, MS, to determine the impact of soybean planting date and maturity group on stink bug (Heteroptera: Pentatomidae) populations. Maturity group IV and V soybeans were planted on three planting dates in 2003 and 2004. Planting dateswere lateMarchÐearlyApril, lateAprilÐearlyMay, and lateMayÐearly June. Plotswere sampled weekly with a standard 38.1-cm-diameter sweep net. Planting date and maturity group each had a signiÞcanteffecton stinkbugpopulations. Ingeneral, theearliestplantingdatehad the lowestdensities of stink bugs, whereas the latest planting date had the highest densities of stink bugs. Over the 2-yr period, cumulative numbers of stink bugs (SE) ranged from 17.9 (6.25) per 25 sweeps for the Þrst planting to 190.9 (20.03) per 25 sweeps for the third planting date when averaged across maturity groups. Additionally, stink bug populations were generally lower onmaturity group IV soybeans than on maturity group V soybeans. Cumulative numbers of stink bugs on maturity group IV soybeans averaged 52.4 (26.23) and 25.2 (6.93) in 2003 and 2004, respectively. On maturity group V soybeans, cumulativenumbers of stinkbugs averaged96.9 (28.05) and85.7 (40.84) in 2003 and2004, respectively. Thesedata provide valuable information about thepopulationdynamics of stinkbugs and indicate that early plantings of maturity group IV soybeans in the mid-South will escape heavy stink bug densities.