Jim Kerns

MOST RECENT ABSTRACT TO BE EDITED: The NCSU Plant Disease and Insect Clinic (PDIC) will provide for the identification of plant diseases, insects, weeds, nematodes and abiotic problems through the cooperation of NCSU faculty and staff across several disciplines and with the NC Department of Agriculture and Consumer Services (NCDS&CS). Project personnel will attend national and regional professional meetings and training on special topics and general plant pathology/ entomology/ nematology. PDIC personnel will provide training in pest identification and disease diagnosis in web-based and in-person training sessions, with frequent and timely updates on our social media sites, and with print publications. We will continue to communicate with CES personnel about ways they can improve sample selection and sample data entry to ensure sample quality and accurate diagnosis. Clinic personnel will communicate pest information and diagnostic education to Master Gardeners and CES agents via online meetings. PDIC personnel also will participate in various commodity field days and NCSU and community outreach programs. We will coordinate with NCDA&CS, the North Carolina Forest Service, NC Cooperative Extension, NCSU, USDA-APHIS, and other agencies to communicate pest threats, issue alerts, and provide information about intra-state quarantines as needed.

This research will allow for a greater understanding of factors affecting preemergent herbicide and nematicide degradation in turfgrass areas. Understanding how previous application history, as well as how edaphic factors affect residual pesticide persistence will generate information that may be used to develop best management practices that can be communicated to turfgrass managers to help maximize efficacy. This may include rotating pesticide mode of action or adjusting application rates and timings to optimize efficacy. For example, even though oxadiazon is only absorbed by emerging shoots, it may be beneficial to make a timely split application as opposed to applying the maximum labeled rate initially. This is likely also true for fluopyram given that two split applications perform better than a single application of a high rate. Understanding degradation rates and how they are affected by previous application history and edaphic factors may also influence recommendations and management strategies. In general, data generated from this research will help us gain insight and determine strategies to ensure optimal efficacy is obtained with residual pesticides. Results will be disseminated to turfgrass managers through NCSU TurfFiles, extension outreach, conferences, as well as added to the scientific literature by publishing this experiment along with its results and recommendations.

Large patch is a devastating disease of warm-season turfgrasses. Little research has focused on the biology and management of this disease especially in the Southeastern US. We have proposed the following objectives to enhance our understanding of this important disease. Investigate genetic differences among large patch isolates collected from centipedegrass, St. Augustinegrass, zoysiagrasses and bermudagrass. Assess fungicide sensitivity of large patch isolates collected from the aforementioned turfgrasses. Evaluate the influence of temperature on infection of the turfgrasses listed above. Determine optimal timing of fungicide application to prevent large patch development. This research will improve turfgrass quality for numerous residents of NC.

Industrial hemp producers are faced with many challenges from diseases, including a lack of fungicide chemistries. Since the onset of the pilot program, the Plant Disease and Insect Clinic has diagnosed 435 submitted samples. Many of these samples were affected by Fusarium wilt and foliar diseases, which are significantly damaging to industrial hemp. Strain differences in susceptibility to diseases was observed in official variety testing sites, but not all diseases were present at each testing site. An additional constraint is market pressure for organically produced products. To address the management of these damaging fungal pathogens, this project will evaluate strain susceptibility and low-risk, organic, and plant health products for their impact on disease management.

Pythium root rot is a devastating disease of golf course putting greens in the Southeast US. We still have not characterized the pathogens associated with this disease and thus control has suffered. The goal is understand the disease better in order to develop more efficient control measures.

We propose to investigate the amount of fungicide in clippings from golf course putting greens and fairways after applications targeting take-all root rot, Pythium root rot and dollar spot. These diseases are problematic for almost all members of the Carolinas and investigating tactics to improve fungicide efficacy targeting these diseases is warranted. We also plan to examine if altering mowing schedules for various periods of time after fungicide applications improves disease control. Finally, we propose to determine the effective concentrations required to keep the diseases mentioned above suppressed and relate that to the concentrations needed to suppress fungal growth in culture.

Fungicide performance is dictated by numerous factors such as deposition (rate, timing, application equipment and post application irrigation), depletion factors, pathogen aggressiveness and fungicide resistance, that are well characterized in the literature. Previous research conducted in Dr. Gannon������������������s lab demonstrated that 50% of azoxystrobin is removed in clippings when applications are watered in and the turf is mown the day after application. This work was conducted in tall fescue swards that are not mowed as frequently as golf course putting greens. Given that most golf course superintendents frequently combat soilborne diseases with soil drenched applications, it is imperative to understand how much of the fungicide is removed the day after the application with a mower. Our project seeks to quantify the loss of fungicides in clippings 10 days after application of fungicides.

The objective of the cooperative research between North Carolina State University and the USDA Agricultural Research Service is to evaluate, identify, and develop sources of resistance to nematode diseases in maize.

Sting nematode (Belonolaimus longicaudatus) and root-knot nematode (Meloidogyne spp.) are very destructive pests of many crops, including turfgrass. Chemical nematicides and cultural control are the two most effective strategies for managing nematodes, but both have limitations. Chemicals are only effective if they come in contact with the nematode. Vertical distribution of nematodes in the soil column is important, as nematodes closer to the surface are more likely to be affected by higher concentrations of chemicals. Vertical distribution of sting or root-knot nematodes has rarely been researched, but could be important in predicting the most advantageous time to apply chemicals for control. However, if chemicals are not an option then cultural control is necessary to reduce putting green damage. By performing a tolerance screen of both warm and cool-season grasses in this study, information can be provided for course superintendents to pick the best turf cultivar for cultural control of the nematode species present.

This trials is designed to investigate the efficacy of experimental fungicides on the turfgrass disease, fairy ring. Fairy ring is a very important disease of golf course putting greens. North Carolina has 555 golf courses and golf contributes 3 billion dollars to the state's economy. This is important information for the turfgrass managers of NC and Southern US.