Identifying a Potential Trap Crop for a Novel Insect Pest, Halyomorpha halys (Hemiptera: Pentatomidae), in Organic Farms.

The invasive brown marmorated stink bug, Halyomorpha halys, poses significant risk to organic farming systems because they rely on biological control, nonsynthetic inputs, and cultural tactics for pest management. This study evaluated the potential of five crop plants (sorghum, admiral pea, millet, okra, and sunflower) to be used as trap crops under organic production in four mid-Atlantic states. Stink bug (H. halys and endemic species) densities and host plant phenologies were recorded weekly (mid-June through September). Sorghum attracted significantly more H. halys than the other crops evaluated, followed by sunflower and okra. Seasonal average H. halys density was 1.5-4× higher on sorghum than the other crops (P < 0.05), depending on site. Endemic stink bugs were equally attracted to all crops except admiral pea. A significant effect of time was detected (P < 0.0001), with H. halys densities initially higher on sunflower; as the sunflower senesced, sorghum supported significantly higher average H. halys densities. While sunflower and sorghum phenologies differed, these crops together provided a 5-wk attraction period coinciding with peak H. halys activity. The efficacies of pheromone-baited traps, flaming, applying OMRI-approved insecticides (Azera and Venerate), and vacuuming to removing stink bugs were evaluated as a management tactic. Flaming was the most effective treatment against H. halys and endemic stink bugs. Our results suggest that a trap crop composed of sorghum and sunflower may be an effective management tool for the mid-Atlantic stink bug complex, including H. halys. Future research should address the appropriate size and placement of trap crop within the farm.

Distribution and fractionation of phosphorus, cadmium, nickel, and lead in calcareous soils amended with composts.

Composts improve organic carbon content and nutrients of calcareous soils but the accumulation and distribution of phosphorus and heavy metals among various fractions in soil may vary under the south Florida conditions. The accumulation of P, Cd, Ni, and Pb with depth and the distribution of water soluble, exchangeable, carbonate, Fe-Mn oxides, organic and residual forms of each element were investigated in soils amended with municipal solid waste (MSW) compost, co-compost and biosolids compost and inorganic fertilizer (as control). Total concentrations of P, Cd, Ni, and Pb were higher in the 0-22 cm soil layers and decreased considerably in the rock layers. These elements were in the decreasing order of P >> Pb > Ni > Cd. Amounts of water soluble and exchangeable forms of P, Cd, Ni and Pb were negligible at 0-22 cm soil depths except for Cd in the 10-22 cm depth. Amending calcareous soil with either organic or inorganic amendments rendered phosphorus, nickle and lead in the residual form followed by Fe-Mn oxides form in the 0-10 and 10-22 cm soil layers. Cadmium was predominantly in the Fe-Mn oxides fraction followed by the residual and carbonate forms in both soil layers. A significant positive correlation was found between various organic carbon fractions and organic forms of P, Cd and Pb in the surface soil layer. Soil amended with MSW compost had higher concentration of Cd in the organic fraction whereas, co-compost and MSW compost amended soil had higher concentrations of organic Ni fraction in the 0-10 cm soil layer.