Stephen J. Stringer, Arlen D. Draper, Donna Marshall-Shaw, Blair J. Sampson and John J. Adamczyk Jr.
Ebrahiem Babiker, Stephen J. Stringer, Hamidou F. Sakhanokho, John J. Adamczyk Jr. and Arlen D. Draper
Christopher T. Werle, Karla M. Addesso, Blair J. Sampson, Jason B. Oliver and John J. Adamczyk
Invasive ambrosia beetles (Coleoptera: Curculionidae) are an important pest problem at ornamental tree nurseries. Available chemical treatments are not completely effective and, due to the length of the beetle dispersal period and insecticide breakdown, repeated treatments can become costly in terms of application expense and nontarget impacts. Additional options are needed to reduce application frequency and to provide an acceptable level of crop protection. Four treatments were tested using ethanol-injected eastern redbud trees at research sites in Mississippi (MS) and Tennessee (TN) over 2 years (2014–15), with the number of new ambrosia beetle galleries compared over time on 1) nontreated control trees, 2) kaolin-treated trees, 3) bifenthrin-treated trees, and 4) kaolin + bifenthrin (k + b)-treated trees. Kaolin-treated trees rapidly lost their coating after rain events and, at 6 days after treatment (DAT) in TN, no differences were detected in the number of beetle galleries between kaolin and nontreated control trees. Kaolin + bifenthrin-treated trees appeared to retain treatment residue longer, but were not better-protected than bifenthrin-treated trees at any time. Further research is needed to determine whether an adjuvant, such as a surfactant, spreader, or sticker, may enhance the modest impact offered by kaolin in our test, or if a reduction in rates of bifenthrin may be allowable.
Stephen J. Stringer, Donna A. Shaw, Blair J. Sampson, Hamidou F. Sakhanoko, Ebrahiem Babiker, John J. Adamczyk Jr., Mark K. Ehlenfeldt and Arlen D. Draper
Ronald C. Stephenson, Christine E.H. Coker, Benedict C. Posadas, Gary R. Bachman, Richard L. Harkess, John J. Adamczyk and Patricia R. Knight
Due to difficulty in monitoring insect pests, applications of insecticides are frequently conducted on a calendar schedule. However, seasonal variability in pest populations leads to these calendar schedules sometimes being inaccurate. Threshold-based insect management strategies, including use of thresholds with conventional pesticides and with use of organic pesticides only, were compared with a conventional calendar approach for yield, management cost, and production value of tomato (Solanum lycopersicum). Effect of cultivar was considered by inclusion of the long season cultivar Celebrity and the short season cultivar Early Girl Bush. These factors were compared for spring and fall seasons during two production years. Greatest total and marketable yields were obtained from use of conventional pesticides according to action thresholds. Use of organic insecticides according to thresholds did not affect yields in comparison with a calendar-based approach. Proportion of fruit rated unmarketable was greater with use of organic insecticides due to reduced efficacy and residual of control. Production costs for the organic threshold-based approach were greater due to increased number of insecticide applications required. Gross margin for both conventional and organic threshold-based insect pest management was greater than for the conventional calendar method. Increased economic return for conventional threshold-based management was due to increased yields. Increase in return for organic threshold management was based on premiums received for organically grown tomatoes. Adoption of conventional threshold-based insect pest management by small-scale producers has the potential to increase production efficiency and value, as well as increase environmental sustainability of production. Economic feasibility of organic production requires access to markets willing to pay significant premiums for organic produce. Further research to evaluate economic and yield impacts of production practices for small-scale farms is needed.