Epacris longiflora, an Australian heather
Professor
B.S. Michigan State University (1979)
M..S. Michigan State University (1982)
Ph.D. University of Florida (1987)
238 Winston Hall
(336) 758-5321
kronka@wfu.edu
Areas of Interest
Structural Evolution of the Chloroplast Genome in Mycorrhizal and Insectivorous Ericales. Phylogenetic Systematics and Biogeography of Ericaceae (Rhododendron, Vaccinium and related tropical taxa, Gaultheria) and Polygonaceae (buckwheat family). Monographic, revisionary and floristic treatments in Ericaceae.
Research
My general area of research interest is the phylogenetic relationships of flowering plants. In my lab we use molecular and morphological data to study the evolution of members of the blueberry family (Ericaceae) and the buckwheat family (Polygonaceae).
Most recently we have begun a study of the evolution of the chloroplast genome structure across the order Ericales. This clade includes several groups with unusual or distinctive physiology. Clades such as Ericaceae contain groups with unique mycorrhizal forms and associations. Ericaceae also include non-chlorophyllous species. Other clades within the large order Ericales are insectivorous (e.g., pitcher plants; Sarraceniaceae). The comparison of the structure and gene content in 10 representatives of the Ericales indicates significant inversions, duplications, gene losses and changes in transcription direction, especially in those species with unusual mycorhizzae or insectivore. Other changes in chloroplast genome structure are coincident with floral developmental features that are not functionally related (directly).
Our previous work on Ericaceae has led to the first modern classification of the family that integrates information from DNA sequence data, morphology and anatomy. Some of the major phylogenetic and biogeographical findings made in my lab include: determining the placement of the Australian heathers (formerly Epacridaceae) as sister to the blueberry and wintergreen groups within Ericaceae, the temperate origin of tropical Vaccinium and relatives, a new clade of Neotropical blueberries (Andean Clade) with a unique mycorrhizal association, the diversification of South African heathers (Erica) from northern European ancestors and a Laurasian origin for the Ericaceae.
The results of studies in the Polygonaceae show that this herbaceous group of plants has striking patterns of parallel evolution in floral and vegetative features including the reduction of leaves to minute bracts and shifts in floral symmetry from complex (the ancestral state in the family) to simple. Our studies in this group have also revealed more biodiversity within the woody tropical members of the family than previously known, with 2 new genera described, Salta and Magoniella. Using both molecular and morphology based analyses we have also developed the first modern (only monophyletic groups are named) classification of Polygonaceae, clarifying previously confused relationships.
At this time we are finishing a collaborative project on the wintergreen group (Gaultherieae) that includes the phylogeny and biogeography of several distinctive clades from the Old and New World tropics. The results of this study further support a Northern Hemisphere origin (Laurasia) for Ericaceae (tropical Gaultheria are derived from temperate ancestors) and highlight the role of hybridization as a factor in speciation in many of the Chinese species.
Students interested in Master’s or Doctoral studies in these (or other) groups are encouraged to contact me via email (kronka@wfu.edu).
Selected Publications
Gillespie, E.L. and K.A. Kron. 2013. Molecular phylogenetic relationships and morphological evolution within the tribe Phyllodoceae (Ericoideae, Ericaceae), Systematic Botany 38:752-763.
Schuster, T.M., S.D. Setaro and K.A. Kron. 2013. Age estimates for the buckwheat family Polygonaceae based on sequence data calibrated by fossils and with a focus on the amphi-Pacific Muehlenbeckia. PlosOne: 8:e61261-e61267.
Gillespie, E.L. and K.A. Kron. 2013. Molecular phylogenetic analysis of the circumboreal genus Cassiope (Ericaceae) reveals trends in some morphological and wood anatomy characters and likely reticulate evolution. Rhodora 115:221-249.
Judd, W.S., N.C. Melvin III, K. Waselkov, K.A. Kron. 2013. A taxonomic revision of Leucothoe (Ericaceae; Tribe Gaultherieae). Brittonia 22 pages, July online DOI 10.1007/s12228-012-9295-4 – in press.
Fajardo, D., D. Senalik, M. Ames, H. Zhu, S. Steffan, R. Harbut, J. Polashock, N. Vorsa, E. Gillespie, K. Kron, J. Zalapa. 2013. Complete chloroplast genome sequence of Vaccinium macrocarpon: structure, gene content and rearrangements as revealed by next generation sequencing. Tree Genetics & Genomes 9:489-498. (published online November 2012).
KA Kron. 2012. Empetrum (Ericaceae). pp. 700 in Baldwin, B. et al. (ed.s) The Jepson Manual: Vascular plants of California. 2nd edition. University of California Press.
KA Kron. 2012. Kalmia (Ericaceae). pp. 702 in Baldwin, B. et al. (ed.s) The Jepson Manual: Vascular plants of California. 2nd edition. University of California Press.
KA Kron. 2012. Menziesia (Ericaceae). pp. 703 in Baldwin, B. et al. (ed.s) The Jepson Manual: Vascular plants of California. 2nd edition. University of California Press.
KA Kron and WS Judd. 2012. Rhododendron (Ericaceae). pp. 706-707. in Baldwin, B. et al. (ed.s) The Jepson Manual: Vascular plants of California. 2nd edition. University of California Press.
EL Gillespie and KA Kron. 2012. A new tribe, Bryantheae (Ericoideae: Ericaceae), composed of disjunct genera from South America and Japan. Brittonia 64:73–75.
W Judd, NC Melvin, K Waselkov, and KA Kron. 2012. Taxonomic revision of Eubotrys (Ericaceae, Gaultherieae). Brittonia. 64:165-178.
TM Schuster, JL Reveal, and KA Kron. 2011. Phylogeny of Polygoneae (Polygonaceae: Polygonoideae). Taxon 60: 1653–1666.
PW Fritsch, L Lu, CM Bush, BC Cruz, KA Kron, and D-Z Li. 2011. Phylogenetic Analysis of the Wintergreen Group (Ericaceae) based on Six Genic Regions. Systematic Botany 36:990–1003.
TM Schuster, KL Wilson, and KA Kron. 2011. Phylogenetic relationships of Muehlenbeckia, Fallopia, and Reynoutria (Polygonaceae) investigated with chloroplast and nuclear sequence data. International Journal of Plant Sciences 172:1053-1066.
SD Setaro and KA Kron. 2011. Neotropical and North American Vaccinioideae (Ericaceae) share their mycorrhizal Sebacinales – an indication for concerted migration? PLoS currents 3:RRN1227
A Sanchez, TM Schuster, JM Burke, and KA Kron. 2011. Taxonomy of Polygonoideae (Polygonaceae): A new tribal classification. Taxon 60:151-160.
A Sanchez and KA Kron. 2011. Phylogenetic relationships of Triplaris and: Re-delimitation of the recognized genera and two new genera for Tribe Triplarideae (Polygonaceae). Systematic Botany 36:702-710.
JM Burke, A Sanchez, KA Kron, and M Luckow. 2010. Placing the woody tropical genera of Polygonaceae: A hypothesis of character evolution and phylogeny. American Journal of Botany 97:1377–1390.
E Gillespie and KA Kron. 2010. Molecular phylogenetic relationships and a revised classification of the subfamily Ericoideae (Ericaceae). Molecular Phylogenetics and Evolution 56:343–354.
CM Bush, WS Judd, and KA Kron. 2010. The phylogeny of Leucothoë s.l. (Ericaceae: Vaccinioideae) based on morphological and molecular data (ndhF, matK, and nrITS). Systematic Botany 35:201-206.
CM Bush, S Wagstaff, P Fritsch, and KA Kron. 2009. The phylogeny, biogeography and morphological evolution of Gaultheria (Ericaceae) from Australia and New Zealand. Australian Systematic Botany 22:229-242.
A Sanchez, T Schuster, and KA Kron. 2009. A large scale phylogeny of Polygonaceae. International Journal of Plant Sciences. International Journal of Plant Science 170:1044-1055.
A Sanchez and K Kron. 2009. Afrobrunnichia and Brunnichia and their relationships within Polygonaceae. Taxon. 58:781-792.
WS Judd and KA Kron. 2009. Rhododendron, pp. 455-473 in Elisens, et al. (ed.s) Flora North America Volume 8. Oxford University Press.
KA Kron. 2009. Epigaea, pp. 475 in Elisens, et al. (eds) Flora North America Volume 8. Oxford University Press.
KA Kron. 2009. Therorhodion, pp. 453-454 in Elisens, et al. (eds) Flora North America Volume 8. Oxford University Press.
KA Kron and EA Powell. 2009. Molecular systematics of Rhododendron subgenus Tsutsusi. Edinburgh Journal of Botany 66:81-96.