Oviposition and Sex Ratio of the Redbanded Stink Bug, Piezodorous guildinii, in Soybean

Abstract

Redbanded stink bug, Piezodorus guildinii (Westwood), is a significant soybean pest across the mid-south region of the United States. The objectives of these studies were to characterize: (1) redbanded stink bug oviposition in relationship to soybean maturity group (MG), plant structure, crop phenology, and vertical distribution within the plant canopy; and (2) redbanded stink bug adult sex ratios in relationship to soybean phenology. A total of 5645 redbanded stink bug eggs in 421 egg masses (clusters) were field collected from naturally-occurring populations in MG IV and V soybean over a three year period (2009 to 2011). The mean number of eggs within a cluster was 16.6 ± 0.3. Plant structures by MG interactions were highly significant with more egg masses oviposited on leaves in MG IV (79.4%) and more on pods in MG V (72.7%). The ratio of females to males was similar in all soybean growth stages except R5, where the sex ratio increased to 1.4:1, coinciding with peak oviposition. Only 29.9% of egg clusters in MG IV and 18.3% of egg clusters in MG V were oviposited in the upper 35 cm of the soybean canopy. Based on these results, sampling strategies and insecticide application placement for stink bugs may require modification.

Optimization study on spatial distribution of rice based on a virtual plant approach

“…Though we did not validate our model with an independent dataset, a comparison with the recent literature shows that this result is within the range of optimal row spacing suggested by other studies, i.e. 15-20 cm of row spacing was recommended to produce maximum yields by Hardke et al [27], and 18-27 cm by Dunn et al [28]. It is understood that this result was obtained under a number of simplifications, e.g.…”

Epicuticular hydrocarbons of the redbanded stink bug Piezodorus guildinii (Heteroptera: Pentatomidae): sexual dimorphism and alterations in insects collected in insecticide‐treated soybean crops

“…Considering both the incapacity of nymphs and eggs to fully escape insecticide action and the history of field applications in this case, the changes observed in the epicuticular composition could be the result of the insecticide exposure at sublethal doses of eggs and nymphs that later turn into adults. This might be occurring since chemical treatment often results inefficient due to issues with canopy penetration 56 …”

“…This might be occurring since chemical treatment often results inefficient due to issues with canopy penetration. 56 One of the mechanisms proposed to contribute to insecticide resistance is known as 'cuticular factor', and involves a thickening of insect surface that leads to reduced insecticide penetration across the cuticular barrier. 13,57 In concordance with our results, an increase in the amount of CHC has also been reported in pyrethroid-resistant kissing bugs 12,13 and mosquitoes.…”