Sequential Sampling of Adults and Nymphs of Euschistus heros (F) (Hemiptera: Pentatomidae) on Soybean Bt and Non-Bt

Abstract

To deploy the appropriate management of adults and nymphs of Euschistus heros (Fabricius, 1794) in soybean, we need to construct a sampling plan that allows estimate population density quickly and accurately. This research aimed to perform sequential sampling of adults and nymphs of E. heros in Bt and non-Bt soybeans. For the evaluations we used the method of cloth-to-hit, two regions in which the sample areas where we collected a sample randomly per plot of each trial were installed. Evaluations were performed at 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98 days after emergence (DAE). We adopted the model of contagious distribution, it was constructed a sequential sampling plan in accordance with the Sequential Probability Ratio Test (TSRP). The adopted control level two bugs (adults and nymphs) per cloth beat. The analysis showed two lines of decision: the upper, which is the condition that the adoption of a method of control is recommended, defined by S1 = 6.2449 +0.14244 n; and below, representing that the adoption of some method of control is not recommended, defined by S0 = -6.2449 +0.14244 n. The sampling showed a maximum expected number eight samples to determine the need or otherwise of control. For management based on economic injury level, the expected number of sample units is 17, indicated by the Sequential Probability Ratio Test Wald curve.

Sampling grids for monitoring Euschistus heros infestation in soybean

“…In addition, shorter sampling frequency could help to identify early the presence of insects younger than fourth-instar nymphs, since at this stage the pest is already damaging to soybean (Fonseca et al 2014). Agricultural pest mapping across large fields also need to be better understood (Reay-Jones et al 2010).…”

Chitin Biosynthesis Inhibitors in Euschistus heros Fabr. (Hemiptera: Pentatomidae): Morphometric Alterations in Testes and Nuclei of Testicular Accessory Cells of Adults

“…The Neotropical-brown stink bug Euschistus heros Fabricius (Hemiptera: Pentatomidae) became a major agricultural pest in the productive sector in Brazil (Fonseca, Fernandes, Justiniano, Cavada, & Silva, 2014;Soares, Cordeiro, Santos, Omoto, & Correa, 2018). The expressive reproductive potential and its proliferative index is the main cause that defined your spread in the area.…”