Judith K Brown
Professor, BIO5 Institute
Professor, Entomology / Insect Science - GIDP
Professor, Plant Science
Regents Professor, Plant Sciences
Research Associate Professor, Entomology
Primary Department
(520) 621-1402
Work Summary
Unravel the phylodynamics and transmission-specific determinants of emerging plant virus/fastidious bacteria-insect vector complexes, and translate new knowledge to abate pathogen spread in food systems.
Research Interest
Judith Brown, PhD, and her research interests include the molecular epidemiology of whitefly-transmitted geminiviruses (Begomoviruses, Family: Geminiviridae), the basis for virus-vector specificity and the transmission pathway, and the biotic and genetic variation between populations of the whitefly vector, B. tabaci, that influence the molecular epidemiology and evolution of begomoviruses. Keywords: Plant viral genomics, emergent virus phylodynamics, functional genomics of insect-pathogen interactions

Publications

Cicero, J., & Brown, J. (2011). Functional anatomy of whitefly organs associated with Squash leaf curl virus (Geminiviridae: Begomovirus) transmission by the B Biotype of Bemisia tabaci (Aleyrodidae: Hemiptera). Ann. Entomol. Soc. Am, 104, 261-279.
Ghanim, M., Rosell, R. C., Campbell, L. R., Czosnek, H., Brown, J. K., & Ullman, D. E. (2001). Digestive, salivary, and reproductive organs of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) B type. Journal of Morphology, 248(1), 22-40.

PMID: 11268056;Abstract:

A microscopic analysis of the morphology and ultrastructure of the digestive, salivary, and reproductive systems of adult Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) B type was conducted using light, scanning, and transmission electron microscopy. The internal anatomy of B. tabaci was found to be similar to that reported for Trialeurodes vaporariorum. In a microscopic analysis of the salivary glands, we have shown that each primary salivary gland is composed of at least 13 cells varying in morphology and staining differentially, while the accessory salivary glands are composed of four morphologically similar cells. We analyzed the course of the alimentary canal in B. tabaci, demonstrated the internal morphology of the organs, and clarified the location of the filter chamber relative to other organs in the whitefly. Our observations confirm that the pair of structures extending from the connecting chamber are caeca that may aid in fluid movement through the midgut and are not Malpighian tubules, as previously suggested. We confirm an earlier finding that the whitefly lacks Malpighian tubules, having instead specialized Malpighian-like cells within the filter chamber at the juncture with the internal ileum. Finally, we provide the first scanning electron microscopic analysis showing the reproductive organs of B. tabaci. Our investigation provides clarified terminology for several components of the digestive and excretory system. We also provide drawings and micrographs that will aid future researchers in localizing the internal organs of B. tabaci. We expect our analysis to provide a valuable tool for studying B. tabaci / plant virus interactions and physiological and biological aspects of this insect. © 2001 Wiley-Liss, Inc.

Pietersen, G., Idris, A. M., Krüger, K., & Brown, J. K. (2008). Characterization of Tomato curly stunt virus: A new tomato-infecting begomovirus from South Africa. Plant Pathology, 57(5), 809-818.

Abstract:

The biological and molecular characterization of a virus recognized as a distinct begomovirus species, Tomato curly stunt virus (ToCSV), first observed in South Africa in 1997, is reported here. Whitefly-transmission and host-range studies were carried out using a Bemisia tabaci colony identified as the B-biotype. The experimental host range of ToCSV spanned primarily species in the Solanaceae and Fabaceae. The complete ToCSV genome (2.766 kb) was amplified by PCR, cloned, and the DNA sequence determined. Phylogenetic analysis revealed that ToCSV was most closely related to Tobacco leaf curl Zimbabwe virus (TbLCZV), at 84% nucleotide identity, indicating that ToCSV is a new species in the genus Begomovirus that is probably endemic to southern Africa. The ToCSV genome sequence contained all of the hallmark coding and non-coding features characteristic of other previously recognized monopartite begomoviruses. ToCSV is only the second begomovirus described from southern Africa that infects solanaceous species. Neither a begomoviral DNA-B component nor a satellite-like DNA molecule was detected by PCR in extracts of ToCSV-infected plants. © 2008 The Authors.

Brown, J. K. (2016). The invasive Q-type Bemisia tabaci genome: a tale of gene loss and gene gain.. Gigascience.

Xie, W., Chen, C., Yang, Z., Guo, L., Zhou, X., Wang, D., Chen, M., Huang, J., Wen, Y., Zeng, Y., Liu, Y., Yang, X., Xia, J., Tian, L., Cui, H., Jiao,X, Wu, Q., Wang, S., Xu, B., Li, X., Tan, X., Ghanim, M., Pan, H., Ren, S., Qiu, B., Chu, D., Delatte, Maruthi, H.M.N., Ge, F., Zhou, X., Wang, X., Wan, F., Du, Y., Luo, C., Yan, F., Preisser, E.L., Zhao, J., Gao, Q., Xia, J., Liu, Y., Yin, Y., Brown, J.K., and Zhang, Y. 2017. The invasive Q-type Bemisia tabaci genome: a tale of gene loss and gene gain. Gigascience (accepted with revision).

Brown, J. K. (2017). Previously-elusive badnaviruses associated with symptomatic cacao in Trinidad, the first cacao-infecting viruses in the New World.. Arch. Virol., doi:10.1007/s00705-017-3235-2..

Chingandu, N., Zia-Ur-Rehman, M., Sreenivasan, T.N., Surujdeo-Maharaj, S., Umaharan, P., Guttierez, O.A., and Brown, J.K. 2016. Previously-elusive badnaviruses associated with symptomatic cacao in Trinidad, the first cacao-infecting viruses in the New World. Arch. Virol. doi:10.1007/s00705-017-3235-2.