Search

The species composition and abundance of stink bugs (Heteroptera: Pentatomidae) in corn, Zea mays L., was determined in this on-farm study in Georgia. Seven species of phytophagous stink bugs were found on corn with the predominant species being Nezara viridula (L.) and Euschistus servus (Say). All developmental stages of these two pests were found, indicating they were developing on the corn crop. The remaining five species, Oebalus pugnax pugnax (F.), Euschistus quadrator (Rolston), Euschistus tristigmus (Say), Euschistus ictericus (L.), and Acrosternum hilare (Say), were found in relatively low numbers. Adult N. viridula were parasitized by the tachinid parasitoid Trichopoda pennipes (F.). There was a pronounced edge effect in distribution of stink bugs in corn. Population dynamics of N. viridula and E. servus were different on early and late-planted corn. Oviposition by females of both stink bug species occurred in mid-to-late-May and again mid-to-late-June in corn, regardless of planting date. In early planted fields, if stink bug females oviposited on corn in mid-July, the resulting nymphs did not survive to the adult stage in corn because ears were close to physiological maturity and leaves were senescing. Density of stink bug adults in early planted corn was relatively low throughout the growing season. In late-planted corn, females of both stink bug species consistently laid eggs in mid-to-late-July on corn with developing ears. This habitat favored continued nymph development, and the resulting adult population reached high levels. These results indicate that corn management practices play a key role in the ecology of stink bugs in corn agroecosystems and provide information for designing management strategies to suppress stink bugs in farmscapes with corn.

Although many different insects can be found in rice fields in Florida, stink bugs are currently con sidered the most important pest. Jones & Cherry (1986) reported that the rice stink bug, Oebalus pugnax (F.), was the dominant species comprising >95% of the total stink bug population. Cherry et al. (1998) reported that the stink bug, Oebalus yp silongriseus (DeGeer) was widespread in Florida rice fields. This was the first report of this species being found in commercial rice fields in the United States. Cherry and Nuessly (2010) reported that the stink bug, Oebalus insularis (Stal) is now wide spread in Florida rice fields. This was the first re port of this species being found in commercial rice fields in the United States. Two other stink bug species which attack Flor ida rice are Euschistus ictericus (L.) and the south ern green stink bug, Nezara viridula (L.) (Genung et al. 1979). Previous to this study, these 5 stink bug species were all observed by the author in light trap samples taken at the Everglades Research and Education Center, Palm Beach County, Flor ida. This center is located near the center of the rice producing area in southern Florida. The center itself consists of a mosaic of rice, sugarcane, vege table, turf, and biofuel plots. Nothing is known on the seasonal flight of these 5 rice pests in southern Florida. Hence, the objective of this study was to determine the seasonal flight activity of these 5 stink bug species which attack Florida rice. Flight activity of stink bugs was measured with a large, walk-in black light trap. This trap measured 2 m x 2 m x 2.5 m high and was made of w od with screened sides. On the top was a 15 watt black light with a funnel through which in sects fell into the trap below. The trap was located on the Everglades Research and Education Cen te at Belle Glade, Florida in an area composed of mixed vegetation (various crops, grasses, weeds, trees). The trap was used twice weekly at 3-4-d in tervals from Jan 1, 2008 to Jan 1, 2010. After col lection by vacuuming, stink bugs were frozen for later taxonomic identification and sex determina tion. Samples from within each month for both years were pooled. Thereafter a Least Significant Difference Test (SAS 2010) was conducted to com pare mean monthly catches for each stink bug species. Fifty adults of each species were ran domly selected from samples and dissected to de termine sex ratios. These ratios were tested by Chi-square analysis for each species to determine if the ratios were significantly different from an expected 1 to 1 sex ratio. Adults of both sexes were caught in light trap samples in all 5 species. Chi-square analysis showed that there was no significant deviation from the expected 1 to 1 sex ratio in any of the 5 species. The largest Chi-square value found was 1.62 among the species, this not being significant at alpha = 0.05 (1 df). Monthly catches of stink bugs in the black light are shown in Table 1. Flight activity of all 5 species was remarkably in synchrony, being unimodal with greatest catches in Jul in all spe