West Virginia IPM Report, 2019

NEERA meeting: May 1, 2019, College Park, MD

Presented by Rakesh Chandran

The IPM team members in West Virginia have been carrying out Extension IPM programs in primarily in the areas of Specialty Crops and Urban Horticulture (Master Gardeners).

Significant outputs of past 12 months

1. Implementation of EQIP cost-share program for one commercial orchard in the Potomac Valley Conservation District (2018).
2. Initiation of EQIP cost-share program for two commercial orchards in the Eastern Panhandle Conservation District (2019)
3. Initiation of Citizen Science Project with Master Gardeners to correlate pest emergence/phenology with site-specific weather monitoring activity.
4. Continued publication of quarterly IPM Chronicle newsletter
5. Determination of a degree-day model to manage the invasive weed Japanese stiltgrass (Microstegium vimineum).
6. Continued programming in Greenhouse IPM through deployment of biocontrol agents.
7. Publication of an IPM Brochure
8. Development of an IPM Booth for display at State Fair and other conferences.

Success Stories

Entomology

Mating disruption. Control of clearwing borers in tree fruit has traditionally been provided by the organophosphate insecticide chlorpyrifos. However, surveys of West Virginia growers had indicated that alternatives to chlorpyrifos were needed because of use restrictions, environmental concerns, and/or the products failure to control the pest. Follow-up communications with growers who had indicated the failure of chlorpyrifos to control the pest revealed that control failures were due to improper application timing and not product efficacy. A concerted effort to promote and educate growers on the implementation of mating disruption in orchards was initiated at commodity meetings and workshops. A 3-year demonstration trial was also conducted in Hampshire County, WV, which showed that management of clearwing borers using mating disruption provided equivalent levels of control compared to chlorpyrifos. During the course of the previous grant cycle three major tree fruit growers (Shanholtz, Cook, Orr) in the state have implemented mating disruption in peach and/or apple to control clearwing borers, which has effectively decreased pesticide use and crop loss on these farms. This year, one grower (Shanholtz) expanded the use of mating disruption to include control of codling moth and oriental fruit moth in 80 acres of apples.

Insect monitoring in tree fruit. Major insect pests of tree fruit were monitored in three different locations of the state in 2018 (expanded from one site in 2014–2017; Jefferson Co.) to provide important, time sensitive information to growers in these regions. Monitoring for insect pests was conducted in Jefferson, Hampshire, and Monongalia Counties, WV. Temperature data collected from weather stations located at these sites were used to calculate accumulated degree-days (DD) from biofix for codling moth, Oriental fruit moth, and tufted apple bud moth. Additional pest monitoring for redbanded leafroller, oblique banded leafroller, dogwood borer, peach tree borer, lesser peach tree borer, apple clearwing moth, San Jose scale, spotted tentiform leafminer, tarnished plant bug, and European apple sawfly was also conducted at the Monongalia and Hampshire County locations. Biofix dates and weekly trap captures for insect pests was emailed to growers and county Extension agents. Growers using this information were better able to time insecticide sprays on farms. Two growers (Shanholtz and Ruggles), used this information to control pests on approximately 100 acres of apple.

Monitoring in field/row crops. Monitoring for corn earworm in field/row crops was conducted in 2018 in Wetzel, Wood, Harrison, and Monongalia Counties, WV. Additional pest monitoring for armyworm (true), fall armyworm, European corn borer, and western bean cutworm was also conducted at the Monongalia County location. Weekly trap captures for insect pests was emailed to growers and county Extension agents.

Plant Pathology

Disease alert and prediction to decrease antibiotic use. Spread of vegetable diseases, specifically cucurbit downy mildew (CDM) and late blight of tomato and potato was tracked through CDM-IPMPIPE and USAblight.org, respectively. Disease prediction was provided to the county agents and growers through AgAlert from disease occurrence reports in neighboring counties and analysis of disease conducive weather condition. Once disease was confirmed in the state, it was reported to the online map so that beneficiaries could follow the disease movement and spread. I also participated at the weekly CDM conference calls during the growing season and set sentinel plots to report disease outbreak to the online system and make growers aware of the disease spread with recommendation of measures should be taken. These AgAlerts helped growers taking preventive measures at the time when it was necessary.

Decision support system for apple fire blight management. We set weather stations at the major tree fruit growing counties and subscribed to the disease model data from Spectrum technologies and network of environment and weather applications (NEWA). Fire blight models (Maryblit and Cougar blight) were optimized to predict epiphytic infection period (EIP) and associated risk to relate need for streptomycin spray. Data were accessed remotely, and spray recommendations sent to growers by text messages. Feedback obtained from growers indicated that adoption of preventive measures against CDM and late blight of tomatoes and potatoes prolonged harvest season by two and three weeks, respectively. This would translate achieving higher yield and behavior change of growers. Decision support system for fire blight management helped growers cutting back unnecessary use of streptomycin without compromising level of disease control. This also reduced the risk of antibiotic resistance development in bacterial organism Erwinia amylovora.

Tomato disease management with resistant varieties. As late blight hits tomato and potato production in WV every year, we promoted late blight resistant “WV ’63” tomato together with newly released cultivars “Mountaineer Pride” and “Mountaineer Delight”. These two cultivars possess higher tolerance to Septoria leaf spot (SLS) in addition with late blight resistance. We received overwhelming seed request from small growers all over the state and distributed 1500 seed packets. Each seed packet accompanied with an instruction sheet for seed saving, production technique and feedback. Most feedback came through email as opposed to paper mail. A total of 123 feedbacks were received, where growers rated these three cultivars on a 1–3 scale for total yield, taste and SLS tolerance. Data shown in Fig. 1 indicates highest yield was obtained from “Mountaineer Pride” but “Mountaineer Delight” has better taste and SLS tolerance. We also promoted tomato and pepper grafting as an IPM tool for managing soil-borne diseases. Five workshops on grafting tomatoes and peppers on resistant rootstocks were conducted with growers and plant propagators with an average participation of 15 people. In addition, a demonstration trial was also set at the WVU organic farm to show the benefit of using grafted tomatoes. Due to the involvement of technical component in grafting, not every participant wanted to do it by themselves, but it motivated them buying grafted transplants.

Fig. Compilation of feedback data from tomato growers who received seeds from WVU, showing comparative performance of different varieties in their field/garden. “Mountaineer Pride” shows the greatest yield; “Mountaineer Delight” shows the best taste and greatest SLS tolerance.

Monitoring strobilurin and streptomycin resistance. Fungal and bacterial isolates for apple scab and fire blight, respectively were collected from apple orchards where strobilurin fungicides and streptomycin antibiotic were used. Isolates were subjected to various concentrations of fungicides and antibiotic for assessing sensitivity to chemicals. No resistance in isolates were detected, which correlates with no apparent control failure.

IPM support for diagnostic facilities. Disease diagnosis and management recommendations were provided to all clienteles who contacted WVU plant diagnostic clinic with plant problem.

Outcomes from such diagnostic measures are far reaching as it also educates clientele on management options for such disease outbreak and how to take preventive measures. Video clip from one of our greenhouse growers is the testimony of our service and need for continued support.

Weed Science

Weed ID fact sheets. Proper identification of weeds, especially, non-native invasive, obnoxious, and poisonous weeds is essential to manage them in forages and other crops of West Virginia. In 2018, there were reports of over 30 livestock deaths in the Eastern Panhandle region of the state. Inspection of the sites revealed the presence of Perilla mint (Perilla frutescens) a highly poisonous weed in pastures apart from a few other potentially poisonous weeds such as jimsonweed (Datura stramonium) and nightshades (Solanum spp.) in low numbers. A conscientious effort was taken to come up with fact sheets related to identification and management of 10 such weeds as web-based publications in 2018. Fact sheets were disseminated through social media to WVU Extension clientele during the growing season (May–October). Based on website traffic data analyses there was 8 times more traffic in the page views during this period in 2018 compared to that in 2017. We are currently in the process of consolidating various list-serves to reach out to a wider audience in 2019.

Management of invasive grasses. Effective methods to manage jointhead Arthraxon (Arthraxon hispidus) and Japanese stiltgrass (Microstegium vimenium) invasive annual weeds in pastures and hayfields, was developed as a result of field research during 2016 to 2018. Results were disseminated to growers through the Pesticide Recertification Video. Livestock producers have indicated that they now have a viable tool to control these weeds in their pastures.

County agents reported over 25 calls for recommendations to manage them in 2017 and 2018 as a result of our research efforts.

Weed ID display. A collection of approximately 75 live weed specimen was developed and was displayed at the West Virginia State Fair (the Fair Board requested it be repeated in 2019), State Small Farm Conference, County Agents Training Meeting, etc., and was considered to be useful.

Respectfully submitted by:

Rakesh Chandran, IPM Coordinator, Extension Weed Specialist

Team Members

• Daniel Frank, Extension Entomologist
• Mahfuz Rahman, Extension Plant Pathologist
• Mirjana Danilovich, Extension Consumer Horticulture Specialist
• Allison Nichols, Extension Evaluation Specialist
• Barbara Liedl, Associate Professor (WVSU Collaborator)