- Sorghum defense responses to phloem-feeding aphids. Sorghum, one of the world’s most important monocot crops grown for food, feed, and fuel, suffers severe yield losses due to attack by phloem-feeding insects, including aphids. This project will fill an important gap in current research by utilizing genomic resources to gain insight into the underlying genetic networks and phenotypic traits that contribute to sorghum resistance to aphids. To investigate this, we are utilizing the natural variation in a panel of sorghum inbred lines to elucidate the novel sources of sorghum resistance to sugarcane aphids (SCA). We are using a combination of molecular, biochemical, and electrophysiological approaches to enable better understanding of the genetic basis of sorghum resistance to aphids. The results from this project will provide improved insight as to how endogenous defenses and manipulation of defense signaling networks contribute to the development of more efficient and durable insect pest-resistant varieties of sorghum. This project is recently funded for more than $1.5 Million by the National Science Foundation Faculty Early Career Development Program (CAREER) Program.
- Long-distance defense signaling in maize-insect interactions. We have identified that the aboveground feeding by aphids on maize rapidly sends a yet unidentified signal(s) to the roots that trigger belowground accumulation of the transcripts encoding insecticidal Maize Insect Resistance-Cysteine Protease (Mir1-CP), signifying a potential role of aboveground to belowground communication in maize defense against the phloem-feeding insects. Recently, we have also discovered that OPDA, an intermediate in the jasmonic acid biosynthesis pathway, can contribute to plant defense against insect pests by enhancing callose accumulation. Callose deposition is one of the defense mechanisms utilized by plants that contribute to sieve element occlusion and thus control infestation by phloem sap-feeding aphids. This study provided some interesting leads on how plant signaling mechanisms may limit insect performance by enhancing callose accumulation, thus providing an early line of defense against the insect.
- Herbivore-Associated Molecular Patterns (HAMPs) in altering plant defenses. Plants have evolved complex defense mechanisms to overcome different stresses, including both biotic and abiotic stresses. At the same time, insects produce a suite of Herbivore-Associated Molecular Patterns (HAMPs) present in the insect oral secretions (regurgitant), saliva, and/or frass may either amplify/suppress the induced plant defenses. We are currently employing proteomic techniques to identify the protein components of caterpillar saliva and frass that modulate plant defenses in sorghum.
- Electrical Penetration Graph (EPG) as a tool to study plant-insect interactions. EPG technique is a potent technique to investigate the specifics of plant resistance to piercing/sucking insects. Monitoring this probing behavior is critical in understanding the localization of plant defenses and to determine how plants engage their defense components to restrict aphid feeding. Louis lab has a direct current (DC)-EPG system, which measures the electrical resistance fluctuations produced by the penetrating insect as well as the electromotive force (EMF) signal components that are generated as a result of the aphid feeding. This responsiveness to EMF components is utilized to differentiate between intracellular and intercellular stylet tip positions. When the aphid stylet is inserted intercellularly, the voltage is positive and when inserted intracellularly, the voltage is negative, resulting in potential drops in the signal which is correlated with the physiological condition and defense status of the host.
Click here to see full publication list and citations at Google Scholar. 1Post-doctoral Research Associate in Louis Laboratory, 2Graduate Student in Louis Laboratory, 3Undergraduate student advised by Dr. Louis, *Co-first authors, #Corresponding author
Pingault L1, Varsani S2, Palmer N, Ray S, Williams WP, Luthe DS, Ali JG, Sarath G and Louis J# (2021). Transcriptomic and volatile signatures associated with maize defense against corn leaf aphid. BMC Plant Biology, 21: 138.
2016 - 2020
- Zogli P1, Pingault L1, Grover S2 and Louis J# (2020). Ento(o)mics: the intersection of “omic” approaches to decipher plant defense against sap-sucking insect pests. Current Opinion in Plant Biology, 56: 153-161. DOI: 10.1016/j.pbi.2020.06.002.
- Grover S2, Agpawa E3, Sarath G, Sattler SE and Louis J# (2020). Interplay of phytohormones facilitate sorghum tolerance to aphids. Plant Molecular Biology, DOI: 10.1007/s11103-020-01083-y.
Pingault L1, Palmer NA, Koch KG, Heng-Moss T, Bradshaw JD, Seravalli J, Twigg P, Louis J# and Sarath G# (2020). Differential defense responses of upland and lowland switchgrass cultivars to a cereal aphid pest. International Journal of Molecular Sciences, 21, 7966.
Zogli P1, Alvarez S, Naldrett M, Palmer N, Koch K, Pingault L1, Bradshaw J, Twigg P, Heng-Moss T, Louis J# and Sarath G#(2020). Greenbug (Schizaphis graminum) herbivory significantly impacts protein and phosphorylation abundance in switchgrass (Panicum virgatum). Scientific Reports, 10: 14842.
- Koch KG, Palmer NA, Donze-Reiner T, Scully ED, Seravalli J, Amundsen K, Twigg P, Louis J, Bradshaw JD, Heng-Moss T and Sarath G (2020). Aphid-responsive defense networks in hybrid switchgrass. Frontiers in Plant Science, DOI: 10.3389/fpls.2020.01145.
- Grover S2, Varsani S2, Kolomiets M and Louis J# (2020). Maize defense elicitor, 12-Oxo-phytodienoic acid, prolongs aphid salivation. Communicative & Integrative Biology, 1: 63-66
- Basu S1, Pereira A, Pinheiro DH, Wang H, Valencia-Jiménez A, Siegfried BD, Louis J, Zhou X and Vélez AM.(2019) Evaluation of reference genes for real-time quantitative PCR analysis in southern corn rootworm, Diabrotica undecimpunctata howardi (Barber). Scientific Reports, 9: 10703.
- Palmer NA, Basu S1, Heng-Moss TM, Bradshaw JD, Sarath G# and Louis J#(2019). Fall armyworm (Spodoptera frugiperda Smith) feeding elicits differential defense responses in upland and lowland switchgrass. PLoS One, 14(6): e0218352.
- Varsani S2, Grover S2, Zhou S, Koch KG, Huang PC, Kolomiets M, Williams WP, Heng-Moss T, Sarath G, Luthe DS, Jander G and Louis J# (2019). 12-Oxo-phytodienoic acid acts as a regulator of maize defense against corn leaf aphid. Plant Physiology, 179: 1402-1415.
- Tetreault HM, Grover S2, Scully ED, Gries T, Palmer N, Sarath G, Louis J and Sattler SE (2019). Global responses of resistant and susceptible sorghum (Sorghum bicolor) to sugarcane aphid (Melanaphis sacchari). Frontiers in Plant Science, 10: 145.
- Nalam VJ, Louis J and Shah J (2019). Plant defense against aphids, the pest extraordinaire. Plant Science, 279: 96-107.
- Grover S2, Wojahn B3, Varsani S2, Sattler SE and Louis J# (2019). Resistance to greenbugs in the sorghum nested association mapping population. Arthropod-Plant Interactions, 13: 261-269.
- Chapman K2, Marchi-Werle L, Hunt TE, Heng-Moss T and Louis J# (2018). Abscisic and jasmonic acids contribute to soybean tolerance to the soybean aphid (Aphis glycines Matsumura). Scientific Reports, 8: 1514.
- Koch KG, Donze-Reiner T, Baird LM, Louis J, Amundsen K, Sarath G, Bradshaw JD and Heng-Moss T (2018). Evaluation of greenbug and yellow sugarcane aphid feeding behavior on resistant and susceptible switchgrass cultivars. BioEnergy Research, 8: 165-174.
- Nalam VJ, Louis J, Patel M and Shah J (2018). Arabidopsis-Green Peach Aphid interaction: rearing the insect, no-choice and fecundity assays, and electrical penetration graph technique to study insect feeding behavior. Bio-protocol, 8(15): e2950.
- Basu S1, Varsani S2 and Louis J# (2018). Altering plant defenses: Herbivore-associated molecular patterns and effector arsenal of chewing herbivores. Molecular Plant-Microbe Interactions, 31(1): 13-21.
- Mondal H, Louis J, Archer L, Patel M, Nalam VJ, Sarowar S, Sivapalan V, Root DD and Shah J (2018). Arabidopsis ACTIN-DEPOLYMERIZING FACTOR3 is required for controlling aphid feeding from the phloem. Plant Physiology, 176: 879-890.
- Koch K, Chapman K2, Louis J, Heng-Moss T and Sarath, G (2016). Plant tolerance: A unique approach to control hemipteran pests. Frontiers in Plant Science, 7:1363.
- Ray S, Basu S1, Rivera-Vega L, Acevedo FE, Louis J, Felton GW and Luthe DS (2016). Lessons from the far end: caterpillar frass-induced defenses in maize, rice, cabbage and tomato. Journal of Chemical Ecology, 42:1130–1141.
- Varsani S2, Basu S1, Williams WP, Felton GW, Luthe DS and Louis J# (2016). Intraplant communication in maize contributes to defense against insects. Plant Signaling & Behavior, 11, e1212800.
2011 - 2015
- Louis J#, Basu S1, Varsani S2, Castano-Duque L, Jiang V3, Williams WP, Felton GW and Luthe DS. (2015). Ethylene contributes to maize insect resistance1-mediated maize defense against the phloem sap-sucking corn leaf aphid. Plant Physiology, 169: 313-324.
- Louis J# and Shah J (2015). Plant defence against aphids: the PAD4 signalling nexus. Journal of Experimental Botany, 66 (2): 449-454.
- Louis J#, Peiffer M, Ray S, Luthe DS and Felton GW (2013). Host-specific salivary elicitor(s) of European Corn Borer (Ostrinia nubilalis) induce defenses in tomato and maize. New Phytologist, 199: 63-73.
- Louis J and Shah J (2013). Arabidopsis thaliana - Myzus persicae interaction: shaping the understanding of plant defense against phloem-feeding aphids. Frontiers in Plant Science, 4: 213.
- Louis J#, Luthe DS and Felton GW (2013). Salivary signals of European corn borer induce indirect defenses in tomato. Plant Signaling & Behavior, 10.4161/psb.27318.
- Cao T, Lahiri I, Singh V, Louis J, Shah J and Ayre BG (2013). Metabolic engineering of raffinose-family oligosaccharides in the phloem reveals alterations in carbon partitioning and enhances resistance to green peach aphid. Frontiers in Plant Science, 4: 263.
- Louis J, Gobbato E, Mondal HA, Feys BJ, Parker JE and Shah J (2012). Discrimination of Arabidopsis PAD4 activities in defense against green peach aphid and pathogens. Plant Physiology, 158: 1860-1872. (Featured Cover article, April 2012).
- Louis J*, Mondal HA* and Shah J (2012). Green peach aphid infestation induces Arabidopsis PHYTOALEXIN DEFICIENT4 expression at site of stylet penetration. Plant Signaling & Behavior, 7: 11, 1431-1433. *Co-first authors.
- Singh V, Louis J, Ayre B, Reese JC and Shah J (2011). TREHALOSE PHOSPHATE SYNTHASE11-dependent trehalose metabolism promotes Arabidopsis thaliana defense against the phloem-feeding insect, Myzus persicae. Plant Journal, 67 (1): 94-104.
- Zhu L, Reese JC, Louis J, Campbell L and Chen MS (2011). Electrical penetration graph (EPG) analysis of the feeding behavior of soybean aphids on soybean cultivars with antibiosis. Journal of Economic Entomology, 104 (6): 2068-2072.
2006 - 2010
- Louis J, Kukula K-L, Singh V, Reese JC, Jander G and Shah J (2010). Antibiosis against the green peach aphid requires the Arabidopsis thaliana MYZUS PERSICAE-INDUCED LIPASE1 gene. Plant Journal, 64 (5): 800-811.
- Pallipparambil GR, Reese JC, Avila CA, Louis J and Goggin FL (2010). Mi-mediated aphid resistance in tomato: tissue localization and impact on the feeding behavior of two potato aphid isolates with differing levels of virulence. Entomologia Experimentalis et Applicata, 135: 295-307.
- Louis J, Leung Q, Pegadaraju V, Reese JC and Shah J (2010). PAD4-dependent antibiosis contributes to the ssi2-conferred hyper-resistance to the green peach aphid. Molecular Plant-Microbe Interactions, 23 (5): 618-627.
- Mutti NS, Louis J, Pappan LK, Pappan K, Begum K, Chen MS, Park Y, Dittmer N, Marshall J, Reese JC and Reeck GR (2008). A protein from the salivary glands of the pea aphid, Acyrthosiphon pisum, is essential in feeding on a host plant. Proceedings of the National Academy of Sciences USA, 105 (29): 9965-9969.
- Pegadaraju V*, Louis J*, Singh V, Reese JC, Bautor J, Feys BJ, Cook G, Parker JE and Shah J (2007). Phloem-based resistance to green peach aphid is controlled by Arabidopsis PHYTOALEXIN DEFICIENT4 without its signaling partner ENHANCED DISEASE SUSCEPTIBILITY1. Plant Journal, 52 (2): 332-341.
- Diaz-Montano J, Reese JC, Louis J, Campbell L and Schapaugh WT (2007). Feeding behavior by the soybean aphid (Hemiptera: Aphididae) on resistant and susceptible soybean genotypes. Journal of Economic Entomology, 100 (3): 984-989.
- Voothuluru P, Meng J, Khajuria C, Louis J, Zhu L, Starkey S, Wilde GE, Baker CA and Smith CM (2006). Categories and inheritance of resistance to Russian wheat aphid (Homoptera: Aphididae) biotype 2 in a selection from wheat cereal introduction 2401. Journal of Economic Entomology, 99 (5): 1854-1861.
- Felton GW, Chung SC, Estrada-Hernańdez MG, Louis J, Peiffer M and Tian D (2014). Herbivore oral secretions are the first line of protection against plant induced defenses. Annual Plant Reviews, 47: 37-76.
- Luthe DS, Louis J, Jin S and Castano-Duque L (2013). Expression of the defense gene mir1 depends on herbivore feeding guild and maize genotype. In “Proceedings of the IOBC/WPRS Working Group - Induced resistance in plants against insects and diseases”, Vol 89: 323-327. M Bardin, B Mauch-Mani, S Mazzotta, P Nicot, C Pieterse, J-L Poessel, M Ponchet and A Schmitt, eds. OIBC/OILB, Avignon, France.
- Louis J#, Singh V and Shah J (2012). Arabidopsis thaliana – aphid interaction. The Arabidopsis Book, 10: e0159.
- Parker JE, Rietz S, Wirthmüller L, Bartsch M, Bautor J, Pegadaraju V, Louis J, Singh V, Reese J and Shah J (2008). Processes in plant resistance to invasive pathogens and probing insects. In “Biology of Plant-Microbe Interactions”, Vol 6. M. Lorito, S. L. Woo, and F. Scala, eds. IS- MPMI, St Paul, MN.
|Dr. Joe Louis, Professoremail@example.com|
|Dr. Prince Zogli, Postdoctoral Research Associatefirstname.lastname@example.org|
|Dr. Lise Pingault, Postdoctoral Research Associateemail@example.com|
|Dr. Sajjan Grover, Postdoctoral Research Associatefirstname.lastname@example.org|
|Kait Chapman, Ph.D. Studentemail@example.com|
|Heena Puri, Ph.D. Studentfirstname.lastname@example.org|
|Mia Luong, MS Student (co-advised with Gary Hein)||email@example.com|
|Juan David Betancurt Cardona, MS Studentfirstname.lastname@example.org|
|Earl Agpawa, University of Nebraska-Lincoln Agricultural Research Division Undergraduate Student Research Programemail@example.com|
|Leah Cheney, Lab Research Assistant, Undergraduate Studentfirstname.lastname@example.org|
|Kyler Lawrenson, Lab Research Assistant, Undergraduate Studentemail@example.com|
|Undergraduate students from University of Texas Rio Grande Valley (UTRGV) as part of NSF Summer Research Experience for Undergraduates (REU) Program|
|Adryenna Perez, Summer 2019||Juan Raya, Summer 2019|
|Sajjan Grover, Ph.D. (2017-2021)|
|Karen Da Silva, Ph.D. (2015-2020)|
|Mariana Sanchez, MS (2017 – 2019)|
|Suresh Varsani, Ph.D. (2014 – 2018)|
|Saumik Basu, Postdoctoral Research Associate (2014 – 2017)|
Allison Siekman (Summer 2014)
Zhang Jing (Summer 2014; Research Exchange Student from Northwest Agriculture and Forestry University [NWAFU], China)
Shelby Patak (September 2014 – December 2014)
Anqui Li (Summer 2015; Research Exchange Student from NWAFU, China)
Mengke Yuan (Summer 2015; Research Exchange Student from NWAFU, China)
Yizi Mao (September 2015 – January 2016)
Ellis Johnson (January 2016 – May 2017) (Undergraduate Creative Activities and Research Experience [UCARE] Program, University of Nebraska-Lincoln)
Braden Wojahn (March 2017 – May 2018) (UCARE Program)
Luisa Valencia (August 2017 – July 2018)
Ben Bradley, Lab Research Assistant, Undergraduate Student (May 2019 - August 2019)
Murtaza Nalwala, Lab Research Assistant, Undergraduate Student (September 2019 - December 2019)
The Louis lab organizes and participates in various public scientific education and outreach events. These events include “BugFest”, “Fascination of Plants Day”, “Research Experience for Teachers” Program, “Visits by Scientist” program at Lincoln Public Schools, and “Research Experience for Undergraduate Students” Program.
Heena Puri, Ph.D. student, received the 2021-2022 Milton E. Mohr Fellowship from the Nebraska Center for Biotechnology at the University of Nebraska-Lincoln. Great work Heena!
Congratulations to Sajjan Grover on graduating at May 2021 Graduate Commencement with his Ph.D. He is pictured at right with his diploma and with his advisor, Dr. Joe Louis.
Joe Louis was promoted to full Professor in the Department of Entomology. He is pictured (left) with UNL Biochemistry faculty at the Promotion and Tenure celebration. Joe was among 109 faculty members at the University of Nebraska-Lincoln who were promoted and/or tenured this year.
Congratulations to Sajjan Grover for successfully defending his PhD dissertation! Sajjan is starting his new position as a postdoctoral research associate in our lab beginning February 2021.
Sajjan Grover received the 2020 Kenneth and Barbara Starks Plant Resistance to Insects Graduate Student Award from the Entomological Society of America (ESA) for his research on sorghum-aphid interactions. Sajjan also received the 2020 Lillian and Alex Feir Graduate Student Travel Award in Insect Physiology, Biochemistry, or Molecular Biology from ESA. Congratulations Sajjan!
Joe Louis received a USDA/NIFA grant to study resistance in sorghum to fall armyworm (see news release here)
Sajjan Grover was awarded the 2020 Shear-Miles Fellowship from the Institute of Agricultural and Natural Resources (IANR), University of Nebraska-Lincoln. Congratulations, Sajjan! A luncheon to honor all those receiving Graduate Fellowships will be held later this Fall.
Mia Luong and Earl Agpawa received the Earl and Bertha Ramsey Memorial Fellowship Ephriam and Veallon Hixson Memorial Scholarship, respectively, from the Department of Entomology, University of Nebraska-Lincoln. Congratulations, Mia and Earl!
Kaitlin Chapman (Ph.D candidate) started a new position as Extension Educator in the Lancaster County Extension office in Lincoln, NE. Congratulations, Kait!
Congratulations to Sajjan Grover for receiving first place for his oral presentation in the virtual ESA-NCB/SWB competition.
December 2019Mariana Sanchez at the Graduation Commencement where she received her master's degree. Mariana is pictured with her co-advisors Ana Velez and Joe Louis.
Mariana Sanchez receiving her insect pillow case at the Department of Entomology graduation ceremony.
Congratulations to Sajjan Grover and Earl Agpawa for receiving 2nd Place for Grad Infographic and 2nd Place of Undergrad Poster, respectively, at the 2019 Entomological Society of America’s (ESA) Annual Meeting.
Sajjan Grover and Karen Da Silva received the 2019 Widaman Distinguished Graduate Fellowship and Hardin Distinguished Graduate Fellowship, respectively, on October 10 at the ARD Award Luncheon.
Joe Louis was named as the 2019 recipient of the Early Career Innovation Award from the Entomological Society of America. See news release here and here.
Sajjan Grover and Karen Da Silva were awarded the 2019 Widaman Distinguished Graduate Fellowship and Hardin Distinguished Graduate Fellowship, respectively, from the Institute of Agricultural and Natural Resources (IANR), University of Nebraska-Lincoln. Congratulations, Sajjan and Karen! A luncheon to honor all those receiving Graduate Fellowships will be held later this Fall.
Adryenna Perez and Juan Raya presented their work at the Nebraska Summer Research Symposium (pictured with Sajjan Grover).
Earl Agpawa’s research proposal was awarded a $2,500 grant from the IANR Agricultural Research Division Undergraduate Student Research Program. Congratulations, Earl!
We welcome Drs. Lise Pingault and Prince Zogli as postdoctoral research associates in our lab.
We welcome Adryenna Perez and Juan Raya to our lab from the University of Texas Rio Grande Valley (UTRGV; Kariyat Lab) as part of the NSF Summer Research Experience for Undergraduates (REU) Program.
Suresh Varsani at the Graduation Commencement.
Joe Louis was promoted to Associate Professor and granted tenure at the University of Nebraska-Lincoln Promotion and Tenure celebration.
Kait Chapman and Sajjan Grover received the North Central Branch-Entomological Society of America Student Travel Scholarships to attend the meeting. Mariana Sanchez received the Graduate Student Travel Award from University of Nebraska-Lincoln’s Office of Graduate Studies.
Joe Louis received a five-year $1.5 million Faculty Early Career Development Program (CAREER) award from the National Science Foundation.
Kait Chapman and Suresh Varsani received the North Central Branch-Entomological Society of America Student Travel Scholarships to attend the meeting.
Contact UsEmail: firstname.lastname@example.org Office phone: (402) 472-8098 Lab Location: 309 Entomology Hall
University of Nebraska-Lincoln East Campus
University of Nebraska-Lincoln Entomology Department Page