James Walgenbach

The western flower thrips (WFT) has developed into a major pest of tomato and pepper in North Carolina and other parts of the southeastern US. It transmits tomato spotted wilt virus and feeds directly on fruit causing scarring and gold fleck. Preliminary research suggests its worsening pest status on diversified vegetable farms is the result of two key factors operating at the farmscape level; a locally suitable community of floral hosts that bridge WTF populations within and among years, and the development of spinetoram-resistant populations. The goal of this project is to better understand landscape factors driving WFT population dynamics so as to predict the risk of damage on individual farms, and to evaluate preventive cultural management strategies. Specific objectives are to 1) identify factors contributing to year-to-year persistance of WFT on farms across a diversity of agroecosystems, 2) design and test spatial structuring of crops at the farmscale level to avoid thrips infestations, 3) compare the timing and method of killing cover crops, 3) determine the prevelance of spinetoram resistance on a regional scale, and 4) deliver research findings to stakeholders and implement more sustainable management programs. The goals will be accomplished by assessing WFT population dynamics at the farmscape level across ecoregions of NC and VA, by conducting field studies on weed management and crop rotation to preventively suppress thrips populations, and conduct bioassays to test thrips for spinetoram resistance across NC and VA.

Ambrosia beetles, especially those belonging to the tribe Xyleborini, are recognized as extremely successful invaders worldwide. Two species of ambrosia beetles are especially problematic in nurseries and orchards, namely, the granulate ambrosia beetle, Xylosandrus crassiusculus (Motschulsky) and the black stem borer, Xylosandrus germanus (Blandford). In the U.S., X. germanus tends to be more abundant and problematic in Midwest and the Northeast, while X. crassiusculus dominates the mid-Atlantic and the South. Unlike other wood-boring insects, ambrosia beetles tunnel into host trees to create galleries for rearing offspring and cultivating fungal symbionts serving as the sole source of nutrition for adults and larva. Physiological stressors predispose trees to attack by X. crassiusculus and X. germanus. Ethanol is emitted from stressed trees, and represents an important volatile cue used by ambrosia beetles to locate vulnerable hosts. Infestations of ambrosia beetles can result in branch dieback and tree death. Apart from direct losses of trees from beetle attacks, infestations can render trees unmarketable, increase pest management inputs, decrease integrity of surviving trees and make them vulnerable to secondary infection, and cause rapid decline in apple trees.

This project is a national collaboration to rebuild integrated pest management programs in specialty crops affected by spotted-wing drosophila, Drosophila suzukii. In North Carolina, these crops include blueberries, blackberries, raspberries, and strawberries.

Western flower thrips is a key pest of tomatoes and peppers in NC. This project will investigate new pesticides with unique modes of action for their control, as well as use of reflective mulches to reduce infestation pressure.

The western flower thrips is a key pest of fruiting vegetables, causing direct damage by feeding on fruit, and indirectly by transmitting tomato spotted wilt virus. In recent years it has become a serious pest in certain areas of NC, SC and VA. Increased severity of WFT in certain areas appears to be due to insecticide resistance to the insecticide Radiant (ai = spinetoram). The objectives of this project are to 1) evaluate the extent of WFT resistance to spinetoram among different regions and cropping systems representative of the southeastern US, 2) evaluate cultural control strategies for suppression of WFT in areas of high resistance levels, and 3) extend information to stakeholders through extension activities.

This project focuses on improving biological control of key arthropod pests of organically produced vegetable crops in the southeastern US, including NC. Studies will focus on improving the performance of augmentation releases of Phytoseiulus persimilis and Amblyseius swirskii against the twospotted spider mite by fine tuning releases in tomato plants, develop tomato-adapted strains of predatory mites, and develop grower friendly predatory rearing systems. The project also includes an outreach program to deliver new information to growers.

Western flower thrips is an important pest of tomatoes. Insecticide resistance has made it difficult to control. This project will evaluate different insecticide programs for control.

This project is designed to develop a more sustainable pest management system for management of insect pests in cucurbit cropping systems in the southeastern US. Studies will be conducted to determine the effect of different mulch types and insecticide programs on pest and beneficial arthropod pests, and to assess the effect of different living mulches on pest and beneficial arthropods. An outreach program will be conducted to extend information to stakeholders.

Brown marmorated stink bug is a pest of nation significance in the United States. This project brings together pest control scientists, extension educators, and economists from 17 institutions across the US to develop management strategies to mitigate damage in US specialty crops.

The brown marmorated stink bug is an invasive pest that was first detected in NC in 2009, and became elevated to major pest status in 2015. Apple growers have been forced to use broad spectrum pyrethroid insecticides to control of BMSB, a group of insecticides that are highly disruptive of IPM programs. Pyrethroids eliminate key natural enemies of important secondary pests, which has led to outbreaks of European red mite, San Jose scale and Woolly apple aphid. Hence, since the arrival of BMSB to NC apples, pesticide use has increased dramatically on this crop. This proposal seeks to develop an alternative approach to managing BMSB that will eliminate the need for sprays of broad spectrum pyrethroids, and allow natural enemies to repopulate orchards and reinstitute biological control as the key management strategy for secondary pests. This alternative strategy will consist of an attract and kill approach, whereby BMSB pheromones will be used to lure BMSB to ????????????????killing stations??????????????? consisting of insecticide-impregnated netting. The research will be accompanied by an extension program that will present results to growers at commodity meetings, development of publications, and use of the apple IPM website to extend results to constituents.