In my current postdoctoral work at the University of Maryland (Department of Entomology; Dr. Bill Lamp’s lab) I’m interested in ecology and evolution of plant-insect interactions, and primarily novel interactions between native and introduced species. This is a continuation of my previous postdoctoral work at Wisconsin and doctoral research at Cincinnati. I’m curious what mechanisms (behavioral, molecular, physiological, etc.) drive such novel interactions, and how introduced species become invasive in natural and managed systems. Currently, I’m working on a variety of projects that involve DNA barcoding, microscopy, morphometric analysis, phylogenetics, field and greenhouse work. The topics include (a) host plant usage of the potato leafhopper based on molecular markers for ingested plant DNA; (b) DNA barcoding in isopods; (c) biodiversity of agricultural drainage ditches; (d) herbivore resistance and tolerance in exotic grasses; and (e) external morphology and host plant usage of the invasive spotted lanternfly using molecular approach, light microscopy and scanning electron microscopy. A brief description for some of my projects is below. I will be adding more details as the projects grow.
I’ve been working on the spotted lanternfly (SLF) since last Spring. This emerging invasive insect pest is currently rapidly spreading in the eastern US, and it has been detected in Maryland in October 2018. Our two grant proposals on studying SLF external morphology and its host plants were recently funded by MDA and MAES (yay!) and now I’m spending almost half of my time in the microscope room and the SEM laboratory. I’m curious to see how the lanternfy’s mouthparts and tarsi are so well adapted to feeding and moving on its host trees. Also, I”m about to try our DNA barcoding protocol we’ve developed for another sap-feeder, the potato leafhopper, to confirm the lanternfly’s host plants. Almost a year later, since I started studying this species, I can’t stop being amazed by SLF unique ecology and behavior.
Update – 01/25/19: I’m presenting my intermediate results at the at the Entomological Society of America Annual Meeting, Eastern Branch, March 9-11,2019. Blacksburg, VA.
Update - 02/23/19: I’ve presented at the Annual Meeting of the Maryland Organic Food & Farming Association (Maryland Dept. of Agriculture, Annapolis, MD). My talk was on the lanternfly biology, behavior, and host plant usage.
Update - 02/28/19: I’ve finished the 2nd round of scanning electron microscopy of the lanternfly mouthparts and tarsi. Most of the beautiful SEM images are included in my poster for the upcoming EB-ESA meeting.
Plant DNA detection in insect gut contents is one of the most accurate ways to confirm host plant utilization, determine insect diet and interactions with other organisms. Most of the previous studies that involved molecular analysis of insect gut contents were primarily conducted on leaf-chewing insects, such as beetles, moths, or grasshoppers. Sap-feeders could be more challenging for molecular analysis of their gut contents because phloem sap presumably doesn’t contain plant DNA. However, this method was shown to be effective for potato psyllids (Cooper et al 2016) - apparently, while feeding an insect stylet (a piercing mouthpart) can consume not only phloem sap but can also pick up some of the surrounding plant cells which allows DNA to be detected in the insect gut contents. In this project, we would like to investigate whether (and how) we can apply this method for yet another sap-feeder, the potato leafhopper, to explore its host plant usage.
Update - 07/07/18: we are making some good progress, and we’ve submitted our oral presentation (A. Avanesyan and W. O. Lamp, “Use of molecular markers for plant DNA to determine host plant usage for potato leafhopper, Empoasca fabae”) also to the ESA meeting in Vancouver, BC, Canada.
Update – 11/15/18: presented!
This is an ongoing project in Dr. Lamp’s lab. Using isopods from multiple wetland sites and streams in Maryland Delmarva Bays Wetlands we explore the potential connectivity between wetland and stream communities. Morphological identification of isopod species is tricky, and DNA barcoding, which I’m focusing on, is very helpful for estimating how ‘close’ wetland isopod species are to the isopod species inhabiting streams. I’m currently mentoring three students in this DNA barcoding work, and together with my mentees we isolate and sequence a portion of mitochondrial gene, cytochrome oxidase 1 (CO1), create a reference library of these sequences, and using a BLAST search engine in the NCBI GenBank database we assess species and genera identity of isopods.
Update - 02/22/19: Nina, a high school student, who was working on this project since September 2018, presented her research project earlier this week at her school’s science fair and got 3rd prize! So exciting!
This is a systematic review I was working on last year (manuscript submitted). The review aimed to identify patterns of grasshopper feeding preferences for native versus introduced plants and, consequently, grasshopper potential for biotic resistance of native communities, that (as the review has shown) is surprisingly overlooked in experimental studies on invasion ecology.
Update – 07/07/18: I’ve submitted a poster presentation on this review to the upcoming ESA meeting in Vancouver, BC, Canada. I’m also going to present it here, at the University of Maryland research symposium organized by the Office of Postdoctoral Affairs.
Update – 05/18/18: the manuscript has been submitted!
Although exotic chinese silver grass, a gorgeous ornamental plant and important biofuel source, can be highly invasive in some states, not all of its cultivars are invasive. I’ve been conducting field and greenhouse experiments to explore plant resistance and tolerance to grasshopper herbivory, how these responses differ among Miscanthus cultivars, and whether the initially introduced wild type demonstrates the highest level of herbivore resistance.
I’ve recently joined this ongoing project in Dr. Lamp’s lab, and I am currently ‘torturing’ herbarium plant specimens hoping that they will speak and tell me their taxonomic identity. Having almost zero previous experience in plant identification, so far I have barely advanced to plant family level (with the aid of textbooks and technology). A lot to learn, a lot to do…
Update - 12/17/18: I’m done with ‘torturing’ plant specimens. Plant diversity across different sites in Maryland has been analyzed, the plant data have been ‘matched’ to the spider diversity data, and my labmate, Dylan Kutz, will present the results at the Entomological Society of America Annual Meeting, Eastern Branch, March 9-11,2019. Blacksburg, VA.
In my postdoctoral work at the University of Wisconsin-Madison I studied one of the emerging insect pests – the spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae). This is a highly invasive insect species, which attacks undamaged ripening fruit of a wide variety of soft-skinned fruits and berries. Native to Southeast Asia, currently it is observed in Europe, North America, and South America. Drosophila suzukii has demonstrated a very high dispersal capacity and remarkable phenotypic plasticity – during only a couple of decades since its first introduction in Hawaii, D. suzukii invaded different temperate regions and now is being monitored in many northern and eastern states, as well as Canada.
I work on several projects on different aspects of D. suzukii biology and population distribution. I coordinated a multi-state bait comparison project for determining optimal attractants for D. suzukii. This project was conducted in Minnesota; we set up fly traps with eight different baits and conducted monitoring of D. suzukii in raspberry during several weeks. I also developed experimental design for the spatial and temporal distribution project which was supposed to be conducted later in the season when population of D. suzukii could be established.
I was also actively involved in a project on D. suzukii seasonal phenology focused on overwintering of D. suzukii and the effect of temperature and humidity on D. suzukii seasonal abundance. We are currently writing a paper on D. suzukii seasonal phenology which includes an analysis of the interactions between D. suzukii seasonal abundance and temperature and humidity dynamics during the collecting seasons in 2014-2015.
Additionally, I developed a protocol for tissue preparation, isolating spermathecae, and determining mating status of D. suzukii, which we have applied in our bait comparison and phenology studies. This protocol has been recently published in Insects (Special issue on invasive species). In this paper, we also demonstrated how this protocol can be applied for both field collected flies and flies reared in the lab, including fly specimens stored on a long-term basis.