Grant Information
| Knowledge Area | Subject of Investigation | Field of Science | Percent |
|---|---|---|---|
| 211 - Insects, Mites, and Other Arthropods Affecting Plants | 999 - Citrus, general/other | 1130 - Entomology and acarology | 100% |
Oranges and their citrus relatives are iconic symbols for the state of Florida, so much so that the state beverage is orange juice, the state flower is the orange blossom, and oranges figure prominently on standard vehicle license plates. However, there has been a steady decline in citrus acreage since its peak in 1998 at 785,900 ac (FDACS 2018), which coincides with the establishment of the Asian citrus psyllid (ACP), Diaphorina citri, and the subsequent finding of the bacteria Candidatus Liberibacter (CLas), which is vectored by this insect and thought to be the primary causal agent of citrus greening/ citrus Huanglongbing (HLB) (reviewed in Halbert and Manjunath, 2004). In the most recent agricultural survey (2016-17), citrus acreage in Florida was down to 410,700 ac, which is a decrease in just over 50% of total acreage (FDACS 2018).Due to the dramatic decline and fear of spreading to other regions of the United States, there has been heavy investment in research to manage the spread of CLas by managing the insect vector and testing therapeutic strategies to restore HLB-affected trees. To date, arthropod management efforts have been focused on the local/regional extirpation of ACP using chemical tools while other options are developed and tested. Because there are limited modes of action available to manage ACP, some of which are much more expensive than others, materials with similar active ingredients have been used repeatedly, leading to local populations of resistant psyllids (Tiwari et al. 2011). To help manage this disease complex with an eye towards insecticide resistance management (IRM), area-wide management programs were established, termed Citrus Health Management Areas (CHMAs), that coordinated chemical management programs to ensure both the proper timing of applications and insecticide resistance management by providing growers a spray plan that rotated the mode of action of material applied (Rogers et al. 2011). Area-wide management, as managed by the CHMA system, can be an efficient management strategy to minimize the spread of a pest. However, the effectiveness of these programs is proportional to grower participation. Additionally, refuges in the form of abandoned groves and unmanaged backyard plantings add complication to management programs by enabling both the bacteria and its vector to persist despite concentrated management efforts (NAS 2018).Current management for ACP in Florida relies largely on calendar sprays (Qureshi et al. 2014), but still infestation by psyllids and subsequent infection by CLas persist. To expand management programs, research efforts are now taking integrated approaches to pest and pathogen management. For example, tree flush phenology is being monitored in a similar fashion to previous work on flower bud induction so that sprays for psyllid suppression can be timed to ACP activity periods. And cultural management control, such as metalized reflective mulch are being tested for efficacy in deterring ACP from young trees.The lack of pest and/or pathogen suppression after years of an intensive management scheme highlights the necessity of developing comprehensive, whole grove integrated pest management programs. Such programs use multiple tools from across the scientific disciplines which contribute to citrus production (e.g. entomology, microbiology, horticulture, ecology, engineering). Development and evaluation of new and ongoing integrated arthropod pest management programs will be the focus of my research program at the University of Florida.Related Previous Work & Present OutlookWhile new to the citrus production system, I have contributed significantly to the management of another invasive, economically important pest, spotted wing drosophila (Drosophila suzukii), in blueberry and blackberry production (Diepenbrock and Burrack 2016, Diepenbrock et al. 2016, Diepenbrock et al. 2016, Diepenbrock et al. 2017, 2018, Diepenbrock and McPhie 2018). Additionally, I have experience working with several species of lady beetles (Coleoptera, Coccinellidae), which are important natural enemies of soft-bodied insects, and likely ACP. One key element of this research was determining the influence of habitat on the local retention of several lady beetle species (Diepenbrock and Finke 2013).ObjectivesTo develop and evaluate new and ongoing IPM efforts in citrus, my program will:1) Develop new management tools and evaluate others currently available/under development2) Evaluate commercial products for use in management programs3) Evaluate the potential to expand IPM using habitat manipulation4) Monitor for potential new pests
To develop and evaluate new and ongoing IPM efforts in citrus, my program will:
All work described in this project proposal will be completed either at research stations, grower fields, or a combination of the two. I will evaluate new tools and re-evaluate old methods/tools for pest management in citrus. Immediate projects focus largely on the management of Asian citrus psyllid as a vector for citrus greening disease, with an eye towrds resurgences of old pests and the establishment of new pests.
Target Audience
The research on this project is supports the arthropod management needs of Florida citrus growers
Changes / Problems
Nothing Reported
Training & Professional Development
Nothing Reported
Dissemination Streams
Data from this project are shared at county extension meetings, at our two large citrus conventions (Citrus Expo and Citrus Show), have been published as Arthropod Management Tests (chemical evaluations), extension articles, and indistry magazine articles
Next Reporting Steps
We will continue working with the invasive mealybug and snail pests to develop management options for growers. Additionally, we have been studying an emering citrus greenhouse pest, chilli thrips, and are working towards making management recommendations for our greenhosue producers.
Target Audience
The research from my lab has been aimed at supporting arthropod pest management needs of Florida citrus growers.
Changes / Problems
Nothing Reported
Training & Professional Development
I have been training growers, scouts, and extension professionals on the identification of N. virids and continue to share information with our clientele as we learn it. I have also been part of the newly established IPM In Service Training for extension faculty. This fall I taughtthe IPM introduction to this program and instruction on reporting.
Dissemination Streams
Data are regularly shared with clientele through podcasts, industry publications, extension presentations, and conversations.
Next Reporting Steps
I will continue with our ongoing research and work to implement management for our recently established pests as data are available. <br><br>
<br>What was accomplished under these goals? (1) I have one ongoing project, funded through the HLB MAC program to evaluate a potential repellent for Asian citrus psyllid. Laboratory data have been completed and look promising. Field evaluations were incomplete due to COVID, however, we have enough data to redesign the field implementation for testing in 2021. (2) I am the lead PI on a multi collaborator project funded through the HLB MAC program to evaluate tools being used by growers for their potential to be implemented towards the replanting of new citrus trees within an IPM framework. Growers were already trying to use these tools but with little or no data to support their management decisions. This project is aimed at developing and delivering this information. (3) Working with collaboratores in North FL and GA, we have secured funding to do habitat manipulation work to determine the potential of vegetation structure/diversity towards the management of asian citrus psyllid. Start of work was delayed due to the pandemic, however we have the initial plantings completed and are developing sampling plans to beging in early spring 2021. (4) in the summer of 2019, we discovered a newly established pest in citrus groves in FL, Nipaecoccus viridis (Newstead; see Diepenbrock and Ahmed 2019 publication). Since initial discovery, it has been spreading to other areas in the state and other hosts. In the fall of 2020 we have also foudn chilli thrips (Scirtothrips dorsi) in screenhosue citrus production. Additionally, we have identified a snail pest that has been morving into groves and causing problems with irrigation. <br><br><b>Publications</b><br>
Target Audience
The aufience for my work include citrus growers, citrus extension agents, and citrus pest management professionals.
Changes / Problems
Nothing Reported
Training & Professional Development
Nothing Reported
Dissemination Streams
Results of insecticide trials have been communicated to appropriate industry representatives. Results of management research are shared regularly with regional growers at citrus grower meetings, through extension documents, and articles in the regional industry publication, Citrus Industry,
Next Reporting Steps
Secure additional funding for identified research areas Publish in peer-reviewed academic journals Continue to share results with grower and industry clientele <br><br>
<br>What was accomplished under these goals? 1) Develop new management tools and evaluate other currently available/under development: Proposals submitted for evaluation of a repellent odorant release device and to establish wholistic grove management recommendations for the use of reflective mulch, exclusion bags, and kaolin clay for ACP management purposes. Funding received shortly after this report was due. 2) Evaluate commercial products for use in management programs: In 2019, we performed field efficacy trials for ACP control in areas where insecticide resistance has been documented. We also performed initial field tests and designed a laboratory screening method to evaluate chemistries for use against a recently established pest, Lebbeck Mealybug. 3) Evaluate potential to expand IPM using habitat manipulation- nothign to report for this reporting period 4) Monitor for potential new pests: In May 2019, we were alerted to new damage related to an unknown pest in grower's fields in central FL. We have worked with out state agriculture agency (FDACS-DPI) to document this as a new pest in US commercial citrus and are working with them to document the spread of the pest while also researching management options. <br><br><b>Publications</b><br>